WO2021128434A1 - Easy-to-cut zinc-copper-nickel alloy, preparation method therefor and use thereof - Google Patents

Easy-to-cut zinc-copper-nickel alloy, preparation method therefor and use thereof Download PDF

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WO2021128434A1
WO2021128434A1 PCT/CN2020/000004 CN2020000004W WO2021128434A1 WO 2021128434 A1 WO2021128434 A1 WO 2021128434A1 CN 2020000004 W CN2020000004 W CN 2020000004W WO 2021128434 A1 WO2021128434 A1 WO 2021128434A1
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alloy
zinc
cutting
cupronickel
free
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PCT/CN2020/000004
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French (fr)
Chinese (zh)
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杨泰胜
杨朝勇
熊承义
赵红彬
刘平
周耀华
朱清平
张轩
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宁波博威合金材料股份有限公司
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C30/00—Alloys containing less than 50% by weight of each constituent
    • C22C30/06—Alloys containing less than 50% by weight of each constituent containing zinc
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/02—Making non-ferrous alloys by melting
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C18/00—Alloys based on zinc
    • C22C18/02—Alloys based on zinc with copper as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C30/00—Alloys containing less than 50% by weight of each constituent
    • C22C30/02—Alloys containing less than 50% by weight of each constituent containing copper
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C30/00—Alloys containing less than 50% by weight of each constituent
    • C22C30/04—Alloys containing less than 50% by weight of each constituent containing tin or lead
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C9/00—Alloys based on copper
    • C22C9/04—Alloys based on copper with zinc as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/08—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of copper or alloys based thereon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon
    • C22F1/165—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon of zinc or cadmium or alloys based thereon

Definitions

  • the invention relates to the technical field of copper alloys and their preparation, in particular to a free-cutting zinc-nickel alloy and its preparation method and application. Its applications include household appliances, communication equipment, medical equipment, detection and control instruments, sports equipment, pen-making and other industries .
  • white copper-nickel alloy is silver-white, with medium strength, good elasticity and excellent corrosion resistance, easy to cold and hot processing, and is widely used in decorative materials, electronic and electrical connectors, instrument parts and other fields.
  • ordinary zinc-nickel alloy can hardly meet the needs of parts turning or drilling, such as the pen industry.
  • the zinc-nickel alloys with excellent cutting performance on the market are mainly zinc-nickel alloys containing Pb, such as C79200, C79820, and C79860.
  • Pb has a low melting point and is almost insoluble with Cu, Ni, Zn and other elements. After Pb is added to the Cu-Ni-Zn matrix, Pb is distributed in the matrix in the form of particles. During cutting, the Pb particles are softened or melted due to the heat generated by the friction of the tool, blocking the continuity of the matrix material, and producing a "notch effect", thereby playing a chip breaking effect.
  • Pb particles can also play a role in lubricating and lowering the cutting temperature, thereby increasing the cutting speed, allowing the workpiece to obtain a smooth surface, and improving the quality of the product, which is suitable for machining various parts of different shapes and types.
  • Pb mainly exists in the form of particles in the zinc-nickel alloy system, it will vaporize into the atmosphere at high temperatures, causing pollution to the environment. Especially when the Pb-containing zinc cupronickel is made into parts that are in direct contact with the human body, such as spectacle frames, pen tips, etc., long-term contact will affect the health of the human body. As people pay more attention to the ecological environment and the quality of life, the awareness of environmental protection continues to increase, and the application of copper alloys with high lead content is restricted by environmental protection policies.
  • CN103502488A discloses a Cu-Ni-Mn-Zn alloy, which controls the ⁇ phase and ⁇ phase ratio by adjusting the content of alloying elements and the heat treatment process, and then uses the precipitate formed by the alloy to optimize the cutting performance of the alloy;
  • CN105209653A discloses a An easy-cutting and wear-resisting copper-zinc alloy, which also uses the control of ⁇ phase and ⁇ phase ratio and the formation of iron-nickel-manganese silicides to achieve improvement in cutting performance;
  • CN108350552A discloses a copper-nickel-zinc alloy through nickel , Iron and other elements form spherical or ellipsoidal silicides with silicon to improve alloy performance and cutting performance.
  • the technical problem to be solved by the present invention is to provide a free-cutting white copper-nickel alloy and its preparation method and application in view of the deficiencies of the prior art.
  • the tensile strength of the white copper-nickel alloy is ⁇ 550MPa and the cutting performance reaches more than 80% of that of the lead-zinc white copper C79860. , Which can meet the needs of household appliances, communication equipment, medical equipment, testing and control equipment, sports equipment, pen-making and other industries.
  • the technical solution adopted by the present invention to solve the above technical problems is: a free-cutting zinc cupronickel, the weight percentage composition of which is: Cu: 42.5-47.5wt%, Ni: 8.0-12.0wt%, Mn: 4.0-8.0wt%, Bi: 0.05 to 1.5 wt%, the balance being Zn and unavoidable impurities.
  • Ni is one of the main added elements, which can be infinitely dissolved in copper and has a solid solution strengthening effect.
  • Si, P, Al and other elements are present in the alloy, they can form precipitates with Ni, which has the effect of improving the strength and cutting performance of the alloy.
  • Ni also has the effect of improving the corrosion resistance of the alloy, and its addition determines the strength of the corrosion resistance of the alloy.
  • the Ni content in the zinc cupronickel of the present invention is controlled at 8.0-12.0wt%.
  • Ni content is less than 8.0wt%, the corrosion resistance of the alloy will be weakened, and the color will gradually change from silvery white to slightly yellowish; on the other hand, If the Ni content is greater than 12.0wt%, since the zinc equivalent coefficient of Ni is negative, the ⁇ -phase region of the alloy will expand and the cold deformation performance of the alloy will be improved. However, if there is a certain amount of Bi segregation in the alloy at this time, the alloy will be easily annealed. Cracking occurs. In addition, Ni is a high-priced element, too much content will increase the raw material cost of the alloy.
  • the content of Ni in the zinc cupronickel of the present invention is preferably 9.0 to 11.0 wt%.
  • Mn has a large solid solubility in the zinc cupronickel of the present invention, and also has a solid solution strengthening effect, and Mn has a deoxidizing effect in the alloy smelting process, and can improve the wear resistance of the alloy and improve the cold and heat of the alloy. Processing performance.
  • the addition of Mn can change the color of the alloy to silvery white, but the zinc equivalent coefficient of Mn is positive, and the increase of Mn content will reduce the ⁇ -phase region of the alloy and increase the ⁇ -phase region of the alloy.
  • the ⁇ phase is more corrosive than the ⁇ phase, and too high content will affect the corrosion resistance of the alloy and reduce the cold workability of the alloy.
  • the Mn content in the zinc cupronickel of the present invention is controlled at 4.0-8.0 wt%, preferably 5.0-7.0 wt%.
  • Bi can improve the cutting or drilling performance of the alloy.
  • Bi is almost insoluble in copper and forms a eutectic with copper at 270°C.
  • Bi is mainly distributed on the alloy grain boundaries in the form of thin films.
  • Bi has a low melting point.
  • the heat generated by the interaction between the tool and the material can quickly soften the Bi in the contact part or even make it liquid, thereby playing the role of chip breaking.
  • the content of Bi in the alloy should not be too high.
  • excessive Bi element will reduce the cold and hot workability of the alloy, on the other hand, the high content of Bi will increase the alloy The tendency of annealing to crack. Therefore, the Bi content in the zinc cupronickel of the present invention is controlled to be 0.05 to 1.5 wt%, preferably 0.1 to 1.2 wt%, and more preferably 0.2 to 0.8 wt%.
  • the weight percentage content of Cu, Zn, Mn and Ni satisfies: 0.30 ⁇ (Zn+0.5Mn-1.5Ni)/(Cu+Zn+0.5Mn-1.5Ni) ⁇ 0.44 .
  • (Zn+0.5Mn-1.5Ni)/(Cu+Zn+0.5Mn-1.5Ni) is denoted as X.
  • the content change of Cu, Ni, Zn, Mn in the zinc cupronickel of the present invention and the heat treatment process will affect the phase ratio in the microstructure of the alloy.
  • the zinc cupronickel alloy of the present invention controls the ⁇ phase ratio to 10 ⁇ 60%, preferably 15-45%.
  • X ⁇ 0.30 in the alloy the alloy structure is dominated by ⁇ phase. With this composition content, it is difficult for the alloy to obtain a sufficient amount of ⁇ phase through heat treatment, or even no ⁇ phase.
  • the alloy phase composition is mainly ⁇ phase and ⁇ phase.
  • the ⁇ phase is a hard and brittle phase, which is not conducive to plastic working deformation.
  • the variation range of the control X value of the zinc cupronickel of the present invention is between 0.30 and 0.44, which is to ensure that the alloy of the present invention can not only obtain good cold deformation ability, but also obtain a sufficient proportion of ⁇ phase to improve after appropriate heat treatment process is applied.
  • the control range of the X value in the present invention is more preferably 0.32 to 0.40.
  • the zinc equivalent coefficient of Ni is negative, and the increase of its addition will enlarge the ⁇ phase region.
  • the more ⁇ phase in the alloy the better the cold workability of the alloy, but at the same time the greater the stress after the alloy is cold worked.
  • the alloy has a high probability of longitudinal cracking during one or more stretching annealing processes, especially in the second and subsequent stretching annealing of the hot-extrusion strand. This cracking is closely related to the stress release rate and the content and distribution of Bi. In the annealing process of the tensile deformed alloy, the residual stress will be gradually released. When the stress release rate is too large, the release stress per unit time will be large.
  • the present invention controls the weight percentage composition of the zinc cupronickel, and the weight percentage content of Ni and Bi satisfies: 9 ⁇ 100(Ni+10Bi) ⁇ 23, preferably 11 ⁇ 100(Ni+10Bi) ⁇ 20.
  • the average area of a single Bi particle in the microstructure of the cross-section of the zinc cupronickel is less than 100 ⁇ m 2 , preferably not more than 60 ⁇ m 2 .
  • the Bi particles have a large aggregation area and the grain boundary is brittle, it will affect the cold and hot working deformation of the alloy.
  • the average crystal grain size of the ⁇ phase in the microstructure of the cross-section of the zinc cupronickel is less than 90 ⁇ m, and the area content of the ⁇ phase is 10-60%.
  • the average grain size of the ⁇ phase in the microstructure of the cross-section of the zinc cupronickel of the present invention is controlled below 90 ⁇ m.
  • the larger the average grain size of the ⁇ phase the worse the coordination during grain deformation and the increase in the probability of alloy inhomogeneity deformation. Reduce the processing and forming performance of the alloy terminal.
  • the average crystal grain size of the zinc white copper ⁇ phase of the present invention is further preferably controlled to 5 to 70 ⁇ m.
  • the weight percentage composition of the zinc cupronickel also includes at least one of the following elements: Co: 0.005 to 2.0 wt%, Pb: 0.0001 to 0.2 wt%, Te: 0.005 to 1.0 wt%, S: 0.001 to 0.2 wt%, Se: 0.001 to 0.2 wt%, Ca: 0.005 to 0.2 wt%, Sb: 0.005 to 1.0 wt%, Si: 0.005 to 2.0 wt%, P: 0.001 to 0.5 wt%, Al: 0.005 to 1.0 wt% , Fe: 0.005 ⁇ 2.0wt%, Mg: 0.005 ⁇ 2.0wt%, B: 0.0001 ⁇ 0.2wt%, As: 0.0001 ⁇ 0.2wt%, Sn: 0.005 ⁇ 2.0wt%, Cr: 0.005 ⁇ 1.0wt%, Zr :0.001 ⁇ 0.3wt%, Ti: 0.001 ⁇ 0.3wt%, mixed rare earth: 0.0001 ⁇ 0.2
  • the synergistic effect of adding Co element and Ni to the zinc cupronickel of the present invention can further improve the strength and stress corrosion cracking resistance of the alloy.
  • Co is a high-priced metal, too much addition will significantly increase the raw material cost of the alloy. Therefore, the content of the optional Co element in the zinc cupronickel of the present invention is controlled at 0.005 to 2.0 wt%.
  • Pb mainly exists in the zinc-nickel alloy system in the form of particles, which can play a role in lubricating and reducing the cutting temperature, and can increase the cutting speed, but it will vaporize into the atmosphere at high temperatures and cause pollution to the environment. Therefore, it needs to be strictly restricted as a hazardous substance. Therefore, the content of Pb in the zinc cupronickel of the present invention is controlled within 0.0001 to 0.2 wt%, preferably 0.0001 to 0.09 wt%.
  • Te is almost insoluble in copper, and can form a brittle compound Cu 2 Te with copper, which is dispersed in the matrix and intracrystalline, and the second phase of Cu 2 Te formed is similar to that of lead and bismuth, with low hardness and chip breaking effect Obviously, the cutting performance of the zinc cupronickel can be improved.
  • the content of the optional Te element in the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.6 wt%.
  • the eutectic reaction between S, Se and Cu in the zinc cupronickel of the present invention generates Cu 2 S and Cu 2 Se respectively.
  • Cu 2 S and Cu 2 Se are beneficial to the cutting performance of zinc cupronickel, and their principle is similar to that of Te improving cutting performance.
  • the content of optional S and Se elements in the zinc cupronickel of the present invention are both controlled within 0.001 to 0.2 wt%, preferably 0.005 to 0.2 wt%.
  • the Ca added in the zinc cupronickel of the present invention has the effect of improving the cutting or drilling performance of the alloy.
  • Calcium is almost insoluble in copper and is distributed in the matrix in the form of Ca particles.
  • the Ca element has high activity and is easily burnt during smelting. If the content is too high, the viscosity of the melt will increase and the alloy casting is difficult.
  • the optional Ca content of the zinc cupronickel of the present invention is greater than 0.2 wt%, cracks are likely to occur during extrusion and hot processing, and transverse cracks in the cold deformation process are also easier to germinate. Therefore, the optional Ca element content in the zinc cupronickel of the present invention is controlled within 0.005 to 0.2 wt%.
  • Sb is similar to Bi and is brittle in nature. But unlike Bi, Sb is partially dissolved in copper and forms brittle intermetallic compounds with Cu to improve the cutting performance of the alloy. Excessive content will increase tool wear. Therefore, the optional Sb element content in the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.5 wt%.
  • the zinc equivalent coefficient of Si in the copper alloy is a relatively large positive value, which has the effect of expanding the ⁇ phase region of the alloy and can improve the cutting performance of the alloy.
  • Si and Ni form NiSi compound, which has the effect of increasing the strength of the alloy.
  • the high content of Si is beneficial to increase the ⁇ phase and improve the cutting performance of the alloy, it will also increase the content of NiSi compound, thereby increasing the wear of the tool during operation.
  • the content of the optional Si element in the zinc cupronickel of the present invention is controlled within 0.005 to 2.0 wt%, preferably 0.005 to 0.5 wt%.
  • P has the effect of deoxidizing and refining grains, and can form Cu 3 P with Cu to improve the cutting performance of the alloy; P can also form NiP phase with Ni to increase the strength of the alloy.
  • P content exceeds 0.5 wt%, the alloy has an increased tendency to crack during high temperature extrusion.
  • the optional P element content of the zinc cupronickel of the present invention is controlled within 0.001-0.5 wt%, preferably 0.001-0.2 wt%.
  • Al and Ni form a NiAl compound, which improves the strength of the alloy.
  • the zinc equivalent coefficient of Al is positive, which can expand the beta phase region of the alloy, and Al can form a dense protective film Al 2 O 3 on the surface of the alloy, which has the effect of improving the corrosion resistance of the alloy.
  • the optional Al element content of the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.5 wt%.
  • Fe has the effect of refining alloy grains, and can form FeP compounds with P or exist in the form of elemental iron to improve the mechanical properties of the alloy.
  • the optional Fe element content of the zinc cupronickel of the present invention is controlled within 0.005 to 2.0 wt%, preferably 0.005 to 1.0 wt%.
  • Mg is slightly solid soluble in Cu, and the solid solution is relatively small in the ⁇ phase and ⁇ phase of the copper alloy, and the solid solution strengthening effect is not obvious. Mg can form a brittle CuMg intermetallic compound with Cu, which is distributed within the grain and on the grain boundary. This feature helps chip breaking in the turning process, thereby improving the cutting performance of the alloy.
  • the optional Mg element content of the zinc cupronickel of the present invention is controlled within 0.005 to 2.0 wt%, preferably 0.005 to 1.0 wt%.
  • B has a similar effect to As, and in addition, B has the effect of grain refinement.
  • the optional As element content of the zinc cupronickel of the present invention is controlled within 0.0001 to 0.2 wt%, and the B element content is controlled within 0.0001 to 0.2 wt%.
  • the optional Sn element content of the zinc cupronickel of the present invention is controlled at 0.005 to 2.0 wt%, preferably 0.005 to 1.0 wt%.
  • the optional Cr element content of the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.6 wt%.
  • Zr has the effect of refining crystal grains, and has a time-effective strengthening effect during the heat treatment process. It can achieve strength enhancement through the formation of Cu 5 Zr and Cu 3 Zr, and can improve the cutting performance of the alloy.
  • the optional Zr element content of the zinc cupronickel of the present invention is controlled within 0.001-0.3 wt%, preferably 0.001-0.1 wt%.
  • Ti is similar to Zr and has the effect of refining crystal grains.
  • the optional Ti element content of the zinc cupronickel of the present invention is controlled within 0.001-0.3 wt%, preferably 0.001-0.1 wt%.
  • Rare earth elements are not solid-soluble in copper, can purify the melt, refine the crystal grains of the alloy as-cast, and improve the mechanical properties of the alloy. At the same time, rare earth can affect the wetting effect of Bi in the alloy, thereby improving the distribution of Bi and reducing bismuth. Segregated at the grain boundary.
  • the content of rare earth elements in the zinc cupronickel of the present invention is controlled within 0.0001-0.2wt%.
  • the tensile strength of the zinc cupronickel is ⁇ 550MPa, and the cutting performance is more than 80% of that of C79860.
  • the preparation method of the free-cutting zinc-nickel alloy of the present invention includes the following steps: melting and casting ⁇ extrusion ⁇ stretching ⁇ intermediate annealing ⁇ stretching ⁇ annealing before finished product ⁇ stretching ⁇ finished product.
  • the intermediate annealing process is as follows: first heat up to 100-350°C at a heating rate of less than 15°C/min, hold for 5 to 240 minutes, and then heat up to 500-720°C at a heating rate of less than 15°C/min, Keep warm for 1 ⁇ 24h,
  • the zinc cupronickel of the present invention can be processed into bars, wires and the like according to different application requirements. Taking the bar as an example, the preparation process of the zinc cupronickel of the present invention is:
  • Process 1 casting ⁇ extrusion ⁇ pickling ⁇ stretching (planing) ⁇ intermediate annealing ⁇ pickling ⁇ stretching ⁇ annealing before finished product ⁇ pickling ⁇ stretching ⁇ finished product.
  • Process 2 casting ⁇ rolling ⁇ intermediate annealing ⁇ pickling ⁇ stretching (planing) ⁇ annealing before finished product ⁇ pickling ⁇ stretching ⁇ finished product.
  • the number of stretching and annealing can be appropriately increased.
  • the alloy casting of the present invention can be semi-continuous casting or full continuous casting.
  • the casting temperature is 1000 ⁇ 1200°C, preferably 1020 ⁇ 1120°C. Due to the high content of Zn in the alloy, the casting temperature exceeding 1200°C will easily cause a large amount of Zn. Problems such as volatilization and coarse as-cast structure.
  • high casting temperature will increase the solubility of gas in the melt, and the increase in melt suction will easily cause pores in the center of the ingot; if the casting temperature is too low, the surface of the alloy ingot will easily be cold. The internal center shrinkage and porosity tend to increase.
  • the mold can be equipped with electromagnetic stirring equipment.
  • the electromagnetic stirring can promote the melt exchange in the mold, thereby reducing the outer surface and the center.
  • the temperature difference of the melt at the location and the temperature gradient from the outside to the inside of the melt are reduced.
  • the alloy as-cast structure is mainly equiaxed crystals; in addition, electromagnetic stirring can break the initially solidified dendritic structure to achieve fine structure ⁇ .
  • the alloy of the present invention is a two-phase alloy, which has good hot workability.
  • the method of extruding billet can make the alloy have a denser and more uniform structure.
  • the extrusion temperature is selected from 650 to 820°C, preferably 700 to 780°C.
  • the extrusion temperature is high, the ⁇ phase in the alloy structure increases, the alloy has better high temperature plasticity, and the extrusion force is reduced.
  • the alloy extrusion temperature is high, the temperature of the alloy extruded billet will be higher, and a large amount of ⁇ phase will remain in the extruded billet at this time.
  • the extrusion temperature is high, especially when it is close to the solid-liquid two-phase zone of the alloy, it is prone to extrusion due to the presence of Bi in the alloy.
  • the problem of pressure cracking, so the extrusion temperature is controlled below 820°C.
  • the extrusion temperature is low, the content of the ⁇ phase in the alloy is small, and the driving force for dynamic recrystallization during the alloy deformation is small.
  • the extrusion of the alloy during extrusion is large. When the temperature is lower than 650°C, extrusion difficulties are likely to occur. At the end of the extrusion, there may even be a "boggling" phenomenon.
  • the total deformation of the alloy between two annealings does not exceed 70%, and the deformation of the stretching pass is controlled within 10-40%. It is mainly related to the content of ⁇ phase in the material and the uniformity of plastic deformation.
  • the ⁇ phase in the alloy structure is high, due to the effect of tensile stress during the alloy stretching process, the alloy is very easy to germinate transverse cracks at a large processing rate, and even brittle fracture occurs.
  • the pass processing rate is controlled at 10-30%. If the pass processing rate is too small, the surface layer and core of the rod, wire are deformed unevenly, and the residual stress in the alloy is easily increased.
  • the processing amount of the stretching pass can be increased, and the processing rate of the pass can be controlled at 15-40% to avoid uneven structure deformation and improve production efficiency.
  • Intermediate annealing after the alloy is stretched and deformed has two main purposes. One is to soften the alloy for subsequent re-stretching and deformation; the other is to promote the diffusion of Bi on the grain boundary into the grain.
  • the annealing temperature is 500-720°C
  • the holding time is 0.5-12h
  • the annealing temperature is lower than 500°C
  • the alloy softening rate is slow
  • the dislocation density cannot be quickly reduced
  • the annealing efficiency is reduced
  • the temperature is higher than 720 °C, the alloy softens fast, but the content of ⁇ phase will increase during this annealing process, the hardness of ⁇ phase is higher, and the cold working deformation plasticity is worse than ⁇ .
  • the annealed material contains a large amount of ⁇ phase, which will cause subsequent stretching The amount of pass processing is reduced.
  • high temperature annealing can diffuse part of Bi on the grain boundary into the crystal grains, it also makes the crystal grains of the alloy coarse.
  • the annealing temperature of this alloy is preferably 600-680°C.
  • the most likely problem in the annealing process of the alloy of the present invention is cracking. On the one hand, it is related to the distribution and particle size of Bi, and on the other hand, the stress release rate during the annealing process of the material also affects it.
  • the rate of stress release has no significant effect on the cracking of the alloy, but when the alloy has large particles of Bi or Bi segregation, the increase of the alloy's stress release rate will increase the cracking tendency of annealing. Therefore, the alloy of the present invention needs to strictly control the annealing system, and the heating rate of annealing is less than 15°C/min, preferably less than 10°C/min. A fast heating rate will easily lead to a faster stress release rate in the early stage of the alloy, and the alloy's annealing cracking tendency will increase.
  • the alloy of the present invention may further adopt a step annealing method, namely: firstly heat up to 100-350°C at a heating rate less than 15°C/min, hold for 5 to 240 minutes, and then use a heating rate less than 15°C/min Raise the temperature to 500 ⁇ 720°C for 1 ⁇ 24h. Keep the temperature at a low temperature of 100-350°C for 5 to 240 minutes, preferably 150-300°C, to remove part of the stress in this annealing interval, thereby reducing the amount and rate of stress release during subsequent heating.
  • a step annealing method namely: firstly heat up to 100-350°C at a heating rate less than 15°C/min, hold for 5 to 240 minutes, and then use a heating rate less than 15°C/min Raise the temperature to 500 ⁇ 720°C for 1 ⁇ 24h. Keep the temperature at a low temperature of 100-350°C for 5 to 240 minutes, preferably 150-300°C, to remove part of the stress in this annea
  • the finishing annealing of the alloy of the present invention can use the same process as the intermediate annealing.
  • the annealing process at this stage determines the final phase ratio of the alloy.
  • the increase in the content of ⁇ phase is beneficial to increase the cutting performance of the alloy.
  • the alloy needs to control the content of ⁇ phase. For example, in the pen tip field, there is a necking deformation process at the steel ball end of the pen tip to prevent the steel ball from falling off. If the content of ⁇ phase is too high, there is a risk of necking deformation and cracking.
  • the above-mentioned free-cutting zinc-nickel alloy can be used in household appliances, communication equipment, medical equipment, testing and control instruments, sports equipment and pen-making industries.
  • the present invention has the following advantages:
  • the ⁇ phase is used to improve the strength of the alloy while improving the cutting performance, so that the cutting performance of Bi is similar to that of lead-zinc cupronickel at a lower content.
  • the tensile strength is ⁇ 550MPa, and the cutting performance reaches more than 80% of the C79860 cutting performance.
  • the alloy of the present invention realizes excellent cutting performance and is suitable for high-speed machining of various high-precision parts.
  • the alloy of the present invention can be processed into products such as rods and wires, and is suitable for industries such as household appliances, communication equipment, medical equipment, detection and control instruments, sports equipment, and pen-making.
  • FIG. 2 is an electron microstructure photograph showing the distribution of ⁇ phase in the free-cutting zinc cupronickel of Example 11.
  • the raw materials are made of new materials, and the method of combining new materials with old materials can also be used.
  • the temperature of the smelting furnace is controlled at about 1120°C.
  • the composition test is performed, and the composition is compensated or diluted according to the composition result.
  • the composition is qualified, it is poured into the holding furnace.
  • the temperature of the holding furnace is constant at 1060°C, full continuous casting is carried out, and the ingot specifications are The ingot is sawed and cut into 400mm length.
  • the four stretches adopt one stretch, and the stretching process: Stretch
  • the fourth annealing adopts bell-type furnace annealing, the annealing temperature is 600°C, and the holding time is 5h.
  • Finished product stretching the stretching adopts one-time stretching, and the stretching process: Stretch
  • FIG. 1 is an electron microstructure photograph showing the distribution of Bi in the free-cutting zinc cupronickel of Example 11;
  • FIG. 2 is an electron microstructure photograph showing the ⁇ -phase distribution in the free-cutting zinc cupronickel of Example 11.
  • the small white particles in Figure 1 are Bi element particles, and the dark phase in Figure 2 is the ⁇ phase.
  • Comparative Example 1 meets the standard grade of lead-zinc cupronickel C79860, and Comparative Example 2 meets the composition range of the present invention, but does not contain bismuth; Comparative Example 3 is outside the content range of the alloy composition of the present invention.
  • the performance test of the above examples proves that compared with C79860 and the comparative alloys other than the alloy composition of the present invention, the alloy of the present invention has excellent cutting performance, strength and comprehensive performance.

Abstract

Disclosed is an easy-to-cut zinc-copper-nickel alloy, wherein the composition thereof, in weight percentage, is: Cu: 42.5-47.5 wt%, Ni: 8.0-12.0 wt%, Mn: 4.0-8.0 wt%, and Bi: 0.05-1.5 wt%, the balance being Zn and inevitable impurities. The easy-to-cut zinc-copper-nickel alloy can be processed into products such as rods and wires. The preparation process therefor comprises: fusion casting → extruding → stretching → intermediate annealing → stretching → pre-finished product annealing → stretching → finished product. The easy-to-cut zinc-copper-nickel alloy has an improved cutting property, and the alloy strength is improved by using a β phase, and same has a cutting performance similar to that of a lead-zinc-copper-nickel alloy under the condition of a relatively low Bi content. The easy-to-cut zinc-copper-nickel alloy has a tensile strength of ≥ 550 MPa, has a cutting performance reaching 80 percent or above that of the lead-zinc-copper-nickel alloy C79860, and can meet requirements of industries such as household appliances, communication equipment, medical equipment, detection and control instruments, sports equipment, and pen manufacturing.

Description

一种易切削锌白铜及其制备方法和应用Free-cutting zinc-nickel alloy and its preparation method and application 技术领域Technical field
本发明涉及铜合金及其制备技术领域，具体是一种易切削锌白铜及其制备方法和应用，其应用包括家用电器、通讯设备、医用设备、检测和控制仪器、运动器材、制笔等行业。The invention relates to the technical field of copper alloys and their preparation, in particular to a free-cutting zinc-nickel alloy and its preparation method and application. Its applications include household appliances, communication equipment, medical equipment, detection and control instruments, sports equipment, pen-making and other industries .
背景技术Background technique
锌白铜的外观呈银白色，具有中等的强度，良好的弹性及优异的耐蚀性能，易于冷热加工，被广泛应用于装饰材料、电子电器接插件和仪表零件等领域。在某些要求零件结构精细、尺寸精度高、加工速率快的领域，普通锌白铜难以满足零件车削或钻削加工的需求，如笔头行业等。The appearance of white copper-nickel alloy is silver-white, with medium strength, good elasticity and excellent corrosion resistance, easy to cold and hot processing, and is widely used in decorative materials, electronic and electrical connectors, instrument parts and other fields. In some fields that require fine parts structure, high dimensional accuracy, and fast processing speed, ordinary zinc-nickel alloy can hardly meet the needs of parts turning or drilling, such as the pen industry.
目前，市场上切削性能较为优异的锌白铜合金主要为含Pb的锌白铜，如C79200、C79820、C79860等。Pb的熔点低，与Cu、Ni、Zn等元素几乎不固溶，在Cu-Ni-Zn基体上添加Pb元素后，Pb以质点的形式分布于基体中。切削时，Pb质点由于刀具摩擦产生的热量而软化或熔化，阻断基体材料的连续性，产生“切口效应”，从而起到断屑作用。同时，Pb质点还能起到润滑和降低切削温度的作用，从而提高切削速度，使工件获得光滑的加工表面，提高产品的品质，适合各种不同形状类型零件的机加工。At present, the zinc-nickel alloys with excellent cutting performance on the market are mainly zinc-nickel alloys containing Pb, such as C79200, C79820, and C79860. Pb has a low melting point and is almost insoluble with Cu, Ni, Zn and other elements. After Pb is added to the Cu-Ni-Zn matrix, Pb is distributed in the matrix in the form of particles. During cutting, the Pb particles are softened or melted due to the heat generated by the friction of the tool, blocking the continuity of the matrix material, and producing a "notch effect", thereby playing a chip breaking effect. At the same time, Pb particles can also play a role in lubricating and lowering the cutting temperature, thereby increasing the cutting speed, allowing the workpiece to obtain a smooth surface, and improving the quality of the product, which is suitable for machining various parts of different shapes and types.
由于Pb主要以质点的形式存在于锌白铜体系合金中，在高温时会气化进入大气，对环境造成污染。尤其是当含Pb锌白铜制作成与人体直接接触的零件，如镜架、笔头等，长期接触会影响到人体的健康。随着人们对生态环境、生活质量的重视，环境保护意识不断增强，含铅量高的铜合金的应用受到环保政策的限制。Because Pb mainly exists in the form of particles in the zinc-nickel alloy system, it will vaporize into the atmosphere at high temperatures, causing pollution to the environment. Especially when the Pb-containing zinc cupronickel is made into parts that are in direct contact with the human body, such as spectacle frames, pen tips, etc., long-term contact will affect the health of the human body. As people pay more attention to the ecological environment and the quality of life, the awareness of environmental protection continues to increase, and the application of copper alloys with high lead content is restricted by environmental protection policies.
针对市场对易切削锌白铜合金的需求，国内外铜合金制造企业开展了一系列关于易切削锌白铜合金的开发工作，并获得了一定的成果。CN103502488A公开了一种Cu-Ni-Mn-Zn合金，其通过调整合金元素含量及热处理工艺控制α相和β相比例，再则利用合金形成的沉淀物实现合金切削性能的优化；CN105209653A公开了一种易切削耐磨的铜锌合金，其同样采用控制α相和β相比例以及形成的铁-镍-锰的硅化物以实现切削性能的改善；CN108350552A公开了一种铜镍锌合金，通过镍、铁等元素与硅形成球形或椭球型硅化物，实现合金性能及切削性能的提升。然而实践发现，通过添加某些元素提高锌白铜组织中β相比例或通过元素之间形成沉淀物来实现合金的易切削性能，在一定程度上，虽可改善锌白铜合金材料的车削及钻削性能，但在对小型零件的加工成型时仍然存在局限性，主要表现为小孔钻屑后排屑不畅，堵刀、断刀等问题，切削性能与含铅锌白铜相比仍存在明显差距。因此，开发一种同时适用小型零部件机械加工的易切削锌白铜变得尤为重要。In response to the market's demand for free-cutting zinc-nickel alloys, domestic and foreign copper alloy manufacturers have carried out a series of development work on free-cutting zinc-nickel alloys, and have achieved certain results. CN103502488A discloses a Cu-Ni-Mn-Zn alloy, which controls the α phase and β phase ratio by adjusting the content of alloying elements and the heat treatment process, and then uses the precipitate formed by the alloy to optimize the cutting performance of the alloy; CN105209653A discloses a An easy-cutting and wear-resisting copper-zinc alloy, which also uses the control of α phase and β phase ratio and the formation of iron-nickel-manganese silicides to achieve improvement in cutting performance; CN108350552A discloses a copper-nickel-zinc alloy through nickel , Iron and other elements form spherical or ellipsoidal silicides with silicon to improve alloy performance and cutting performance. However, it has been found in practice that by adding certain elements to increase the β phase ratio in the zinc-nickel alloy structure or by forming precipitates between the elements to achieve the cutting performance of the alloy, to a certain extent, although it can improve the turning and drilling of the zinc-nickel alloy material Performance, but there are still limitations in the processing and forming of small parts, mainly due to poor chip removal after small hole drilling, tool blockage, tool breakage, etc. There is still a significant gap in cutting performance compared with lead-zinc cupronickel . Therefore, it is particularly important to develop a free-cutting zinc-nickel alloy that is suitable for machining small parts at the same time.
发明内容Summary of the invention
本发明所要解决的技术问题是，针对现有技术的不足，提供一种易切削锌白铜及其制备方法和应用，该锌白铜抗拉强度≥550MPa，切削性能达到铅锌白铜C79860的80％以上，能够满足家用电器、通讯设备、医用设备、检测和控制仪器、运动器材、制笔等行业的需求。The technical problem to be solved by the present invention is to provide a free-cutting white copper-nickel alloy and its preparation method and application in view of the deficiencies of the prior art. The tensile strength of the white copper-nickel alloy is ≥550MPa and the cutting performance reaches more than 80% of that of the lead-zinc white copper C79860. , Which can meet the needs of household appliances, communication equipment, medical equipment, testing and control equipment, sports equipment, pen-making and other industries.
本发明解决上述技术问题所采用的技术方案为：一种易切削锌白铜，其重量百分比组成为：Cu：42.5～47.5wt％、Ni：8.0～12.0wt％、Mn：4.0～8.0wt％、Bi：0.05～1.5wt％，余量为Zn和不可避免的杂质。The technical solution adopted by the present invention to solve the above technical problems is: a free-cutting zinc cupronickel, the weight percentage composition of which is: Cu: 42.5-47.5wt%, Ni: 8.0-12.0wt%, Mn: 4.0-8.0wt%, Bi: 0.05 to 1.5 wt%, the balance being Zn and unavoidable impurities.
本发明易切削锌白铜中，Ni是主添加元素之一，在铜中可无限互溶，具有 固溶强化作用。当合金中存在Si、P、Al等元素时，可与Ni形成沉淀物，具有提升合金强度和切削性能的效果。此外，Ni还具有提升合金耐蚀性能的作用，其添加量决定了合金耐蚀性能的强弱。本发明锌白铜中Ni含量控制在8.0～12.0wt％，一方面若Ni含量低于8.0wt％，则合金的耐蚀性能减弱，颜色会逐渐由银白色变成微淡黄色；另一方面，若Ni含量大于12.0wt％，由于Ni的锌当量系数为负值，合金的α相区会扩大，合金的冷变形性能提升，但若此时合金中Bi存在一定量的偏聚，合金退火易出现开裂现象。加上Ni是高价格元素，含量过多会增加合金的原材料成本。本发明锌白铜中Ni含量优选9.0～11.0wt％。In the free-cutting zinc cupronickel of the present invention, Ni is one of the main added elements, which can be infinitely dissolved in copper and has a solid solution strengthening effect. When Si, P, Al and other elements are present in the alloy, they can form precipitates with Ni, which has the effect of improving the strength and cutting performance of the alloy. In addition, Ni also has the effect of improving the corrosion resistance of the alloy, and its addition determines the strength of the corrosion resistance of the alloy. The Ni content in the zinc cupronickel of the present invention is controlled at 8.0-12.0wt%. On the one hand, if the Ni content is less than 8.0wt%, the corrosion resistance of the alloy will be weakened, and the color will gradually change from silvery white to slightly yellowish; on the other hand, If the Ni content is greater than 12.0wt%, since the zinc equivalent coefficient of Ni is negative, the α-phase region of the alloy will expand and the cold deformation performance of the alloy will be improved. However, if there is a certain amount of Bi segregation in the alloy at this time, the alloy will be easily annealed. Cracking occurs. In addition, Ni is a high-priced element, too much content will increase the raw material cost of the alloy. The content of Ni in the zinc cupronickel of the present invention is preferably 9.0 to 11.0 wt%.
Mn在本发明锌白铜中具有较大的固溶度，也具有固溶强化作用，且Mn在合金熔炼过程中有脱氧的效果，并能提升合金的耐磨性能，以及改善合金的冷、热加工性能。Mn的添加量增加可使合金的颜色向着银白色转变，但Mn的锌当量系数为正值，Mn含量的增加会减小合金的α相区，增加合金的β相区。β相与α相相比易腐蚀，含量过高会影响合金的耐蚀性能，并降低合金的冷加工性能。而Mn含量低对合金的热挤压变形不利，存在挤压开裂的风险，退火过程的开裂倾向也增大，合金的耐磨性能减弱。因此，本发明锌白铜中Mn含量控制在4.0～8.0wt％，优选5.0～7.0wt％。Mn has a large solid solubility in the zinc cupronickel of the present invention, and also has a solid solution strengthening effect, and Mn has a deoxidizing effect in the alloy smelting process, and can improve the wear resistance of the alloy and improve the cold and heat of the alloy. Processing performance. The addition of Mn can change the color of the alloy to silvery white, but the zinc equivalent coefficient of Mn is positive, and the increase of Mn content will reduce the α-phase region of the alloy and increase the β-phase region of the alloy. The β phase is more corrosive than the α phase, and too high content will affect the corrosion resistance of the alloy and reduce the cold workability of the alloy. The low Mn content is not good for the hot extrusion deformation of the alloy, and there is a risk of extrusion cracking, the cracking tendency of the annealing process is also increased, and the wear resistance of the alloy is weakened. Therefore, the Mn content in the zinc cupronickel of the present invention is controlled at 4.0-8.0 wt%, preferably 5.0-7.0 wt%.
Bi的添加对合金的切削或钻削性能具有改善作用。Bi几乎不固溶于铜，在270℃时与铜形成共晶体，Bi主要呈薄膜形态分布于合金晶界上。Bi的熔点较低，当合金切削或钻削时，刀具与材料之间的作用产生的热量，可使接触部位的Bi快速软化甚至使其呈液态，从而起到断屑的作用。由于Bi主要以薄膜形态分布于晶界上，因此合金中Bi的含量不宜过高，一方面过高的Bi元素会降低合金的冷、热加工性能，另一方面，含Bi量高会增加合金退火开裂的倾向。因此本发 明锌白铜中Bi含量控制在0.05～1.5wt％，优选0.1～1.2wt％，进一步优选0.2～0.8wt％。The addition of Bi can improve the cutting or drilling performance of the alloy. Bi is almost insoluble in copper and forms a eutectic with copper at 270°C. Bi is mainly distributed on the alloy grain boundaries in the form of thin films. Bi has a low melting point. When the alloy is cut or drilled, the heat generated by the interaction between the tool and the material can quickly soften the Bi in the contact part or even make it liquid, thereby playing the role of chip breaking. Since Bi is mainly distributed on the grain boundaries in the form of thin films, the content of Bi in the alloy should not be too high. On the one hand, excessive Bi element will reduce the cold and hot workability of the alloy, on the other hand, the high content of Bi will increase the alloy The tendency of annealing to crack. Therefore, the Bi content in the zinc cupronickel of the present invention is controlled to be 0.05 to 1.5 wt%, preferably 0.1 to 1.2 wt%, and more preferably 0.2 to 0.8 wt%.
作为优选，该锌白铜的重量百分比组成中，Cu、Zn、Mn和Ni的重量百分比含量满足：0.30≤(Zn+0.5Mn-1.5Ni)/(Cu+Zn+0.5Mn-1.5Ni)≤0.44。Preferably, in the weight percentage composition of the zinc cupronickel, the weight percentage content of Cu, Zn, Mn and Ni satisfies: 0.30≤(Zn+0.5Mn-1.5Ni)/(Cu+Zn+0.5Mn-1.5Ni)≤0.44 .
下文将(Zn+0.5Mn-1.5Ni)/(Cu+Zn+0.5Mn-1.5Ni)记为X。本发明锌白铜中Cu、Ni、Zn、Mn元素含量变化及热处理工艺会影响合金微观组织中的相比例，为使合金具有良好的切削性能，本发明锌白铜合金将β相比例控制在10～60％，优选15～45％。当合金中X＜0.30时，合金组织以α相为主，在该成分含量下，合金通过热处理难于获得足够量的β相，甚至无β相。当合金中X＞0.44时，合金相组成主要为α相和β相。X值过大时，甚至出现γ相。γ相属于硬脆相，不利于塑性加工变形。本发明锌白铜控制X值的变化范围在0.30～0.44之间，是为保证本发明合金在施加适当的热处理工艺后，既可获得良好的冷变形能力，又可获得足够比例的β相以提升切削性能，本发明X值的控制范围进一步优选0.32～0.40。Hereinafter, (Zn+0.5Mn-1.5Ni)/(Cu+Zn+0.5Mn-1.5Ni) is denoted as X. The content change of Cu, Ni, Zn, Mn in the zinc cupronickel of the present invention and the heat treatment process will affect the phase ratio in the microstructure of the alloy. In order to make the alloy have good cutting performance, the zinc cupronickel alloy of the present invention controls the β phase ratio to 10~ 60%, preferably 15-45%. When X<0.30 in the alloy, the alloy structure is dominated by α phase. With this composition content, it is difficult for the alloy to obtain a sufficient amount of β phase through heat treatment, or even no β phase. When X>0.44 in the alloy, the alloy phase composition is mainly α phase and β phase. When the X value is too large, γ-phase even appears. The γ phase is a hard and brittle phase, which is not conducive to plastic working deformation. The variation range of the control X value of the zinc cupronickel of the present invention is between 0.30 and 0.44, which is to ensure that the alloy of the present invention can not only obtain good cold deformation ability, but also obtain a sufficient proportion of β phase to improve after appropriate heat treatment process is applied. For cutting performance, the control range of the X value in the present invention is more preferably 0.32 to 0.40.
Ni的锌当量系数为负值，其添加量的增加会扩大α相区，合金中α相越多，合金的冷加工性能越好，但同时合金冷加工后的应力也越大。当合金中的Bi含量不满足上述关系式时，合金在一次或多次拉伸退火过程中纵裂概率大，尤其是在热挤压线坯第二道及之后的拉伸退火。这种开裂与应力释放速率及Bi的含量和分布情况密切相关。拉伸变形后的合金在退火过程中，残余应力会逐渐释放，当应力释放速率过大时，单位时间的释放应力大。Bi在晶界分布会减弱晶界的结合力，且分布越密集，晶界的结合力将越小。当应力的释放力超过晶界的结合力时，材料出现沿晶界开裂。因此，作为优选，本发明控制该锌白铜的 重量百分比组成中，Ni和Bi的重量百分比含量满足：9≤100(Ni+10Bi)≤23，优选11≤100(Ni+10Bi)≤20。The zinc equivalent coefficient of Ni is negative, and the increase of its addition will enlarge the α phase region. The more α phase in the alloy, the better the cold workability of the alloy, but at the same time the greater the stress after the alloy is cold worked. When the Bi content in the alloy does not satisfy the above relationship, the alloy has a high probability of longitudinal cracking during one or more stretching annealing processes, especially in the second and subsequent stretching annealing of the hot-extrusion strand. This cracking is closely related to the stress release rate and the content and distribution of Bi. In the annealing process of the tensile deformed alloy, the residual stress will be gradually released. When the stress release rate is too large, the release stress per unit time will be large. The distribution of Bi at the grain boundary will weaken the binding force of the grain boundary, and the denser the distribution, the smaller the binding force of the grain boundary will be. When the stress release force exceeds the bonding force of the grain boundary, the material cracks along the grain boundary. Therefore, as a preference, the present invention controls the weight percentage composition of the zinc cupronickel, and the weight percentage content of Ni and Bi satisfies: 9≤100(Ni+10Bi)≤23, preferably 11≤100(Ni+10Bi)≤20.
进一步地，该锌白铜横截面的微观组织中单个Bi颗粒的平均面积小于100μm 2，优选不超过60μm 2。一方面若Bi颗粒聚集面积大，晶界脆性大，影响合金的冷、热加工变形，虽然大面积的Bi颗粒有利于断屑，但由于Bi的总含量一定，因而，这意味着Bi的弥散程度减小，合金切削性能的不均匀性趋势增加；另一方面，在退火过程中，由于Bi的表面张力小，Bi的聚集对退火过程中的应力释放较为敏感，极易以Bi聚集区为裂纹源而发生沿晶开裂。 Further, the average area of a single Bi particle in the microstructure of the cross-section of the zinc cupronickel is less than 100 μm 2 , preferably not more than 60 μm 2 . On the one hand, if the Bi particles have a large aggregation area and the grain boundary is brittle, it will affect the cold and hot working deformation of the alloy. Although the large area of Bi particles is beneficial to chip breaking, because the total content of Bi is constant, this means that the dispersion of Bi The degree of reduction of the alloy cutting performance tends to increase the unevenness of the alloy; on the other hand, during the annealing process, due to the small surface tension of Bi, the accumulation of Bi is more sensitive to the stress release during the annealing process, and it is easy to use the Bi accumulation zone as The source of the crack occurs along the crystal cracking.
作为优选，该锌白铜横截面的微观组织中α相的平均晶粒尺寸小于90μm，β相的面积含量为10～60％。本发明锌白铜横截面的微观组织中α相的平均晶粒尺寸控制在90μm以下，α相平均晶粒尺寸越大，晶粒变形过程中的协调性越差，合金不均匀性变形概率增加，降低合金终端的加工成型性能。为获得更为优异的成型性能，本发明锌白铜α相平均晶粒尺寸控制进一步优选5～70μm。Preferably, the average crystal grain size of the α phase in the microstructure of the cross-section of the zinc cupronickel is less than 90 μm, and the area content of the β phase is 10-60%. The average grain size of the α phase in the microstructure of the cross-section of the zinc cupronickel of the present invention is controlled below 90 μm. The larger the average grain size of the α phase, the worse the coordination during grain deformation and the increase in the probability of alloy inhomogeneity deformation. Reduce the processing and forming performance of the alloy terminal. In order to obtain more excellent molding performance, the average crystal grain size of the zinc white copper α phase of the present invention is further preferably controlled to 5 to 70 μm.
作为优选，该锌白铜的重量百分比组成中还包括以下元素中的至少一种：Co：0.005～2.0wt％、Pb：0.0001～0.2wt％、Te：0.005～1.0wt％、S：0.001～0.2wt％、Se：0.001～0.2wt％、Ca：0.005～0.2wt％、Sb：0.005～1.0wt％、Si：0.005～2.0wt％、P：0.001～0.5wt％、Al：0.005～1.0wt％、Fe：0.005～2.0wt％、Mg：0.005～2.0wt％、B：0.0001～0.2wt％、As：0.0001～0.2wt％、Sn：0.005～2.0wt％、Cr：0.005～1.0wt％、Zr：0.001～0.3wt％、Ti：0.001～0.3wt％、混合稀土：0.0001～0.2wt％。Preferably, the weight percentage composition of the zinc cupronickel also includes at least one of the following elements: Co: 0.005 to 2.0 wt%, Pb: 0.0001 to 0.2 wt%, Te: 0.005 to 1.0 wt%, S: 0.001 to 0.2 wt%, Se: 0.001 to 0.2 wt%, Ca: 0.005 to 0.2 wt%, Sb: 0.005 to 1.0 wt%, Si: 0.005 to 2.0 wt%, P: 0.001 to 0.5 wt%, Al: 0.005 to 1.0 wt% , Fe: 0.005～2.0wt%, Mg: 0.005～2.0wt%, B: 0.0001～0.2wt%, As: 0.0001～0.2wt%, Sn: 0.005～2.0wt%, Cr: 0.005～1.0wt%, Zr ：0.001～0.3wt%, Ti: 0.001～0.3wt%, mixed rare earth: 0.0001～0.2wt%.
本发明锌白铜中添加Co元素与Ni协同作用，能够进一步提高合金的强度和抗应力腐蚀开裂性能。但Co属于高价格金属，加入量过多会显著增加合金的原材料成本。因此，本发明锌白铜中将可选的Co元素含量控制在0.005～2.0wt％。The synergistic effect of adding Co element and Ni to the zinc cupronickel of the present invention can further improve the strength and stress corrosion cracking resistance of the alloy. However, Co is a high-priced metal, too much addition will significantly increase the raw material cost of the alloy. Therefore, the content of the optional Co element in the zinc cupronickel of the present invention is controlled at 0.005 to 2.0 wt%.
Pb主要以质点的形式存在于锌白铜体系合金中，能起到润滑和降低切削温度的作用，可以提高切削速度，但在高温时会气化进入大气对环境造成污染。因此作为有害物质需要严格限制。故本发明锌白铜中Pb含量控制在0.0001～0.2wt％，优选0.0001～0.09wt％。Pb mainly exists in the zinc-nickel alloy system in the form of particles, which can play a role in lubricating and reducing the cutting temperature, and can increase the cutting speed, but it will vaporize into the atmosphere at high temperatures and cause pollution to the environment. Therefore, it needs to be strictly restricted as a hazardous substance. Therefore, the content of Pb in the zinc cupronickel of the present invention is controlled within 0.0001 to 0.2 wt%, preferably 0.0001 to 0.09 wt%.
Te几乎不溶于铜中，能够与铜形成脆性化合物Cu 2Te，弥散分布在基体晶间和晶内，且形成的Cu 2Te第二相与铅、铋质点相似，硬度不高，断屑效果明显，从而可提高锌白铜的切削性能。本发明锌白铜中可选的Te元素含量控制在0.005～1.0wt％，优选0.005～0.6wt％。 Te is almost insoluble in copper, and can form a brittle compound Cu 2 Te with copper, which is dispersed in the matrix and intracrystalline, and the second phase of Cu 2 Te formed is similar to that of lead and bismuth, with low hardness and chip breaking effect Obviously, the cutting performance of the zinc cupronickel can be improved. The content of the optional Te element in the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.6 wt%.
本发明锌白铜中S、Se与Cu发生共晶反应，分别生成Cu 2S、Cu 2Se。Cu 2S、Cu 2Se对锌白铜的切削性能有益，其原理与Te提升切削性能的原理相似。本发明锌白铜中可选的S和Se元素含量均控制在0.001～0.2wt％，优选0.005～0.2wt％。 The eutectic reaction between S, Se and Cu in the zinc cupronickel of the present invention generates Cu 2 S and Cu 2 Se respectively. Cu 2 S and Cu 2 Se are beneficial to the cutting performance of zinc cupronickel, and their principle is similar to that of Te improving cutting performance. The content of optional S and Se elements in the zinc cupronickel of the present invention are both controlled within 0.001 to 0.2 wt%, preferably 0.005 to 0.2 wt%.
本发明锌白铜中添加的Ca具有改善合金切削或钻削性能的效果。钙几乎不固溶于铜，以Ca质点的形式分布于基体中。但Ca元素活泼性高，熔炼时极易烧损，含量过高易导致熔体粘度增大，合金浇铸困难。本发明锌白铜可选的Ca含量大于0.2wt％时，挤压热加工时易出现碎裂，冷变形过程中的横裂纹也较容易萌发。因此本发明锌白铜中可选的Ca元素含量控制在0.005～0.2wt％。The Ca added in the zinc cupronickel of the present invention has the effect of improving the cutting or drilling performance of the alloy. Calcium is almost insoluble in copper and is distributed in the matrix in the form of Ca particles. However, the Ca element has high activity and is easily burnt during smelting. If the content is too high, the viscosity of the melt will increase and the alloy casting is difficult. When the optional Ca content of the zinc cupronickel of the present invention is greater than 0.2 wt%, cracks are likely to occur during extrusion and hot processing, and transverse cracks in the cold deformation process are also easier to germinate. Therefore, the optional Ca element content in the zinc cupronickel of the present invention is controlled within 0.005 to 0.2 wt%.
Sb与Bi类似，本身性脆。但与Bi不同的是，Sb部分固溶于铜，并与Cu形成脆性的金属间化合物，改善合金的切削性能，含量过高会增加刀具的磨损。故本发明锌白铜中可选的Sb元素含量控制在0.005～1.0wt％，优选0.005～0.5wt％。Sb is similar to Bi and is brittle in nature. But unlike Bi, Sb is partially dissolved in copper and forms brittle intermetallic compounds with Cu to improve the cutting performance of the alloy. Excessive content will increase tool wear. Therefore, the optional Sb element content in the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.5 wt%.
Si在铜合金中锌当量系数为较大的正值，有扩大合金的β相区的作用，可 提升合金的切削性能。Si与Ni生成NiSi化合物，具有提升合金强度的作用，Si含量高虽有利于增加β相，提升合金切削性能，但其同时会增加NiSi化合物含量，进而增加刀具工作时的磨损。本发明锌白铜中可选的Si元素含量控制在0.005～2.0wt％，优选0.005～0.5wt％。The zinc equivalent coefficient of Si in the copper alloy is a relatively large positive value, which has the effect of expanding the β phase region of the alloy and can improve the cutting performance of the alloy. Si and Ni form NiSi compound, which has the effect of increasing the strength of the alloy. Although the high content of Si is beneficial to increase the β phase and improve the cutting performance of the alloy, it will also increase the content of NiSi compound, thereby increasing the wear of the tool during operation. The content of the optional Si element in the zinc cupronickel of the present invention is controlled within 0.005 to 2.0 wt%, preferably 0.005 to 0.5 wt%.
P具有脱氧和细化晶粒的作用，可与Cu形成Cu 3P，改善合金的切削性能；P也可与Ni可形成NiP相，提升合金的强度。当P含量超过0.5wt％时，合金在高温挤压时开裂倾向增大。本发明锌白铜可选的P元素含量控制在0.001～0.5wt％，优选0.001～0.2wt％。 P has the effect of deoxidizing and refining grains, and can form Cu 3 P with Cu to improve the cutting performance of the alloy; P can also form NiP phase with Ni to increase the strength of the alloy. When the P content exceeds 0.5 wt%, the alloy has an increased tendency to crack during high temperature extrusion. The optional P element content of the zinc cupronickel of the present invention is controlled within 0.001-0.5 wt%, preferably 0.001-0.2 wt%.
Al与Ni形成NiAl化合物，提升合金强度。Al的锌当量系数为正值，可扩大合金的β相相区，Al可在合金表面形成一层致密的保护膜Al 2O 3，具有提高合金耐腐蚀性能的作用。本发明锌白铜可选的Al元素含量控制在0.005～1.0wt％，优选0.005～0.5wt％。 Al and Ni form a NiAl compound, which improves the strength of the alloy. The zinc equivalent coefficient of Al is positive, which can expand the beta phase region of the alloy, and Al can form a dense protective film Al 2 O 3 on the surface of the alloy, which has the effect of improving the corrosion resistance of the alloy. The optional Al element content of the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.5 wt%.
Fe具有细化合金晶粒的作用，可与P形成FeP化合物，或者以单质铁的形式存在，提升合金的力学性能，当铜合金中存在大量的单质Fe颗粒时，合金的耐腐蚀性能减弱。因此本发明锌白铜可选的Fe元素含量控制在0.005～2.0wt％，优选0.005～1.0wt％。Fe has the effect of refining alloy grains, and can form FeP compounds with P or exist in the form of elemental iron to improve the mechanical properties of the alloy. When there are a large number of elemental Fe particles in the copper alloy, the corrosion resistance of the alloy is weakened. Therefore, the optional Fe element content of the zinc cupronickel of the present invention is controlled within 0.005 to 2.0 wt%, preferably 0.005 to 1.0 wt%.
Mg微固溶于Cu，在铜合金α相和β相中固溶均较微量，固溶强化效果不明显。Mg可与Cu形成脆性的CuMg金属间化合物，分布于晶内和晶界上，该特性有助于车削过程的断屑，从而改善合金的切削性能。本发明锌白铜可选的Mg元素含量控制在0.005～2.0wt％，优选0.005～1.0wt％。Mg is slightly solid soluble in Cu, and the solid solution is relatively small in the α phase and β phase of the copper alloy, and the solid solution strengthening effect is not obvious. Mg can form a brittle CuMg intermetallic compound with Cu, which is distributed within the grain and on the grain boundary. This feature helps chip breaking in the turning process, thereby improving the cutting performance of the alloy. The optional Mg element content of the zinc cupronickel of the present invention is controlled within 0.005 to 2.0 wt%, preferably 0.005 to 1.0 wt%.
As可改善合金的脱锌问题，提升合金的耐腐蚀性能，但含量过高会影响合金的加工性能。B具有与As相似的作用，另外B具有细化晶粒的作用。本发明 锌白铜可选的As元素含量控制在0.0001～0.2wt％，B元素含量控制在0.0001～0.2wt％。As can improve the dezincification problem of the alloy and improve the corrosion resistance of the alloy, but too high content will affect the processing performance of the alloy. B has a similar effect to As, and in addition, B has the effect of grain refinement. The optional As element content of the zinc cupronickel of the present invention is controlled within 0.0001 to 0.2 wt%, and the B element content is controlled within 0.0001 to 0.2 wt%.
Sn可以提高合金的力学性能和抗腐蚀性能，微量的Sn可改变Bi的分布，但由于Sn熔点较低，Sn含量过多反而会增加合金退火开裂的倾向，在Sn含量添加大于2.0wt％时尤为明显。因此，本发明锌白铜可选的Sn元素含量控制在0.005～2.0wt％，优选0.005～1.0wt％。Sn can improve the mechanical properties and corrosion resistance of the alloy. A small amount of Sn can change the distribution of Bi. However, due to the low melting point of Sn, too much Sn content will increase the tendency of annealing cracking of the alloy. When the Sn content is added more than 2.0wt% Especially obvious. Therefore, the optional Sn element content of the zinc cupronickel of the present invention is controlled at 0.005 to 2.0 wt%, preferably 0.005 to 1.0 wt%.
Cr可提升合金的耐腐蚀性能，在锌白铜中可形成单质Cr相，提升强度和切削性能，本发明锌白铜可选的Cr元素含量控制在0.005～1.0wt％，优选0.005～0.6wt％。Cr can improve the corrosion resistance of the alloy, and can form elemental Cr phase in the zinc cupronickel to improve the strength and cutting performance. The optional Cr element content of the zinc cupronickel of the present invention is controlled within 0.005 to 1.0 wt%, preferably 0.005 to 0.6 wt%.
Zr具有细化晶粒的作用，在热处理过程中有时效强化作用，通过形成Cu 5Zr、Cu 3Zr实现强度提升，并能改善合金的切削性能。本发明锌白铜可选的Zr元素含量控制在0.001～0.3wt％，优选0.001～0.1wt％。 Zr has the effect of refining crystal grains, and has a time-effective strengthening effect during the heat treatment process. It can achieve strength enhancement through the formation of Cu 5 Zr and Cu 3 Zr, and can improve the cutting performance of the alloy. The optional Zr element content of the zinc cupronickel of the present invention is controlled within 0.001-0.3 wt%, preferably 0.001-0.1 wt%.
Ti与Zr相似，具有细化晶粒的作用，本发明锌白铜可选的Ti元素含量控制在0.001～0.3wt％，优选0.001～0.1wt％。Ti is similar to Zr and has the effect of refining crystal grains. The optional Ti element content of the zinc cupronickel of the present invention is controlled within 0.001-0.3 wt%, preferably 0.001-0.1 wt%.
稀土元素不固溶于铜，可净化熔体，细化合金铸态的晶粒，提高合金的力学性能，同时稀土可以影响Bi在合金中的润湿效应，从而改善Bi的分布形态，减少铋在晶界处偏聚。稀土元素含量在本发明锌白铜中控制在0.0001～0.2wt％。Rare earth elements are not solid-soluble in copper, can purify the melt, refine the crystal grains of the alloy as-cast, and improve the mechanical properties of the alloy. At the same time, rare earth can affect the wetting effect of Bi in the alloy, thereby improving the distribution of Bi and reducing bismuth. Segregated at the grain boundary. The content of rare earth elements in the zinc cupronickel of the present invention is controlled within 0.0001-0.2wt%.
作为优选，该锌白铜的抗拉强度≥550MPa，切削性能为C79860的80％以上。Preferably, the tensile strength of the zinc cupronickel is ≥550MPa, and the cutting performance is more than 80% of that of C79860.
本发明易切削锌白铜的制备方法，其制备工艺流程包括：熔铸→挤压→拉伸→中间退火→拉伸→成品前退火→拉伸→成品。作为优选，所述的中间退火过程为：首先以小于15℃/min的升温速率升温至100～350℃，保温5～240min，然后以小于15℃/min的升温速率升温至500～720℃，保温1～24h，The preparation method of the free-cutting zinc-nickel alloy of the present invention includes the following steps: melting and casting→extrusion→stretching→intermediate annealing→stretching→annealing before finished product→stretching→finished product. Preferably, the intermediate annealing process is as follows: first heat up to 100-350°C at a heating rate of less than 15°C/min, hold for 5 to 240 minutes, and then heat up to 500-720°C at a heating rate of less than 15°C/min, Keep warm for 1～24h,
本发明锌白铜可以根据不同的应用需求加工成棒材、线材等。以棒材为例，本发明锌白铜的制备过程为：The zinc cupronickel of the present invention can be processed into bars, wires and the like according to different application requirements. Taking the bar as an example, the preparation process of the zinc cupronickel of the present invention is:
工艺1：熔铸→挤压→酸洗→拉伸(刨皮)→中间退火→酸洗→拉伸→成品前退火→酸洗→拉伸→成品。Process 1: casting→extrusion→pickling→stretching (planing)→intermediate annealing→pickling→stretching→annealing before finished product→pickling→stretching→finished product.
工艺2：熔铸→轧制→中间退火→酸洗→拉伸(刨皮)→成品前退火→酸洗→拉伸→成品。Process 2: casting→rolling→intermediate annealing→pickling→stretching (planing)→annealing before finished product→pickling→stretching→finished product.
根据试样规格需要，可适当增加拉伸和退火次数。According to the requirements of the sample specifications, the number of stretching and annealing can be appropriately increased.
(1)熔铸：本发明合金熔铸可采用半连铸或全连铸，铸造温度1000～1200℃，优选1020～1120℃，由于合金中Zn含量较高，因此铸造温度超过1200℃易造成Zn大量挥发以及铸态组织粗大等问题，此外铸造温度高会提高气体在熔体中的溶解度，熔体吸气量增加，易造成铸锭中心气孔；铸造温度过低，合金铸锭表面易冷隔，内部中心缩孔和疏松倾向增大。为进一步减少本发明合金铸态的枝晶组织及提升Bi等元素分布的均匀性，结晶器上可配备电磁搅拌设备，电磁搅拌可促使结晶器内的熔体交换，进而减小外表面与中心部位熔体的温差，熔体由外至内的温度梯度减小，此时合金铸态组织主要以等轴晶为主；此外，电磁搅拌可破碎初步完成凝固的枝晶组织，实现组织的细化。(1) Melting and casting: The alloy casting of the present invention can be semi-continuous casting or full continuous casting. The casting temperature is 1000～1200℃, preferably 1020～1120℃. Due to the high content of Zn in the alloy, the casting temperature exceeding 1200℃ will easily cause a large amount of Zn. Problems such as volatilization and coarse as-cast structure. In addition, high casting temperature will increase the solubility of gas in the melt, and the increase in melt suction will easily cause pores in the center of the ingot; if the casting temperature is too low, the surface of the alloy ingot will easily be cold. The internal center shrinkage and porosity tend to increase. In order to further reduce the dendritic structure of the as-cast alloy of the present invention and improve the uniformity of the distribution of Bi and other elements, the mold can be equipped with electromagnetic stirring equipment. The electromagnetic stirring can promote the melt exchange in the mold, thereby reducing the outer surface and the center. The temperature difference of the melt at the location and the temperature gradient from the outside to the inside of the melt are reduced. At this time, the alloy as-cast structure is mainly equiaxed crystals; in addition, electromagnetic stirring can break the initially solidified dendritic structure to achieve fine structure化.
(2)挤压：本发明合金属于两相合金，其具有良好的热加工性能。采用挤压开坯的方式可使合金具有更致密，更均匀的组织。为获得良好的α/β相比例，挤压温度选择650～820℃，优选700～780℃，挤压温度高，合金组织中的β相增加，合金具有较好的高温塑性，挤压力减小，但实际应用中，如果合金挤压温度高，那么合金挤压坯的温度也越高，此时挤压坯中将保留大量的β相。合金在后期进行拉伸或轧制变形时，β相含量越高，材料的脆性越大，拉伸或轧制道 次变形量将减小。此外，在冷变形过程中极易出现撵头碎裂和拉伸脆断的问题，另挤压温度高，尤其当其接近合金的固液两相区时，由于合金中Bi的存在易出现挤压开裂的问题，因此将挤压温度控制在820℃以下。挤压温度低，合金中β相的含量少，加上合金变形过程中发生动态再结晶的驱动力小，合金挤压时的挤压大，当温度低于650℃时，容易出现挤压困难，挤压终了甚至可能出现“闷锭”现象。(2) Extrusion: The alloy of the present invention is a two-phase alloy, which has good hot workability. The method of extruding billet can make the alloy have a denser and more uniform structure. In order to obtain a good α/β ratio, the extrusion temperature is selected from 650 to 820°C, preferably 700 to 780°C. The extrusion temperature is high, the β phase in the alloy structure increases, the alloy has better high temperature plasticity, and the extrusion force is reduced. However, in practical applications, if the alloy extrusion temperature is high, the temperature of the alloy extruded billet will be higher, and a large amount of β phase will remain in the extruded billet at this time. When the alloy undergoes stretching or rolling deformation in the later stage, the higher the content of β phase, the greater the brittleness of the material, and the amount of deformation in the stretching or rolling pass will decrease. In addition, during the cold deformation process, it is prone to cracking and tensile brittle fracture. In addition, the extrusion temperature is high, especially when it is close to the solid-liquid two-phase zone of the alloy, it is prone to extrusion due to the presence of Bi in the alloy. The problem of pressure cracking, so the extrusion temperature is controlled below 820°C. The extrusion temperature is low, the content of the β phase in the alloy is small, and the driving force for dynamic recrystallization during the alloy deformation is small. The extrusion of the alloy during extrusion is large. When the temperature is lower than 650°C, extrusion difficulties are likely to occur. At the end of the extrusion, there may even be a "boggling" phenomenon.
(3)拉伸：合金两次退火之间的总变形量不超过70％，拉伸道次变形量控制在10-40％。其主要与材料中β相含量及塑性变形均匀性有关。当合金组织中β相较高时，合金拉伸过程由于受拉应力的作用，合金极易在大加工率下萌发横裂纹，甚至出现脆断现象。β相含量大于55％时，道次加工率控制在10～30％，道次加工率过小，棒、线表层和芯部变形不均匀，易增加合金内部的残余应力。当β相含量较低时，可以增加拉伸的道次加工量，道次加工率控制在15～40％，以避免组织变形不均匀，并可提升生产效率。(3) Stretching: The total deformation of the alloy between two annealings does not exceed 70%, and the deformation of the stretching pass is controlled within 10-40%. It is mainly related to the content of β phase in the material and the uniformity of plastic deformation. When the β phase in the alloy structure is high, due to the effect of tensile stress during the alloy stretching process, the alloy is very easy to germinate transverse cracks at a large processing rate, and even brittle fracture occurs. When the β phase content is greater than 55%, the pass processing rate is controlled at 10-30%. If the pass processing rate is too small, the surface layer and core of the rod, wire are deformed unevenly, and the residual stress in the alloy is easily increased. When the β-phase content is low, the processing amount of the stretching pass can be increased, and the processing rate of the pass can be controlled at 15-40% to avoid uneven structure deformation and improve production efficiency.
(4)中间退火：合金拉伸变形后的中间退火主要有两个目的，一是主要为了使合金软化，以便后续的再次拉伸变形；二是促使晶界上的Bi向晶内扩散。对于本发明合金而言，退火温度选择500～720℃，保温时间0.5～12h，退火温度低于500℃，合金软化速率慢，无法快速降低位错的密度，降低了退火效率；温度高于720℃，合金软化速度快，但在此退火过程中β相含量会有所增加，β相硬度较高，冷加工变形塑性比α较差，退火后的材料由于含有大量的β相而使后续拉伸道次加工量减小。此外，高温退火虽然可使晶界上的部分Bi向晶粒内扩散，但其同时使合金的晶粒粗大。为获得良好的退火组织，本合金退火温度优选600～680℃。本发明合金退火过程中最易出现的问题是开裂，一方面与Bi 的分布及颗粒大小有关，另一方面材料退火过程中的应力释放速率对其也存在影响。对于普通白铜而言，应力释放的速度对合金开裂影响不显著，但当合金存在大颗粒Bi或Bi偏聚之后，合金的应力释放速率的增加，会增加退火的开裂倾向。因此，本发明合金需要严格控制退火制度，退火的升温速率小于15℃/min，优选小于10℃/min。升温速率快，易导致合金前期的应力释放速率快，合金的退火开裂的倾向增大。本发明合金为避免退火开裂，进一步可采用阶梯退火的方式，即：首先以小于15℃/min的升温速率升温至100～350℃，保温5～240min，然后以小于15℃/min的升温速率升温至500～720℃，保温1～24h。在100～350℃的低温区保温5～240min，优选150～300℃，以在此退火区间去除一部分应力，进而减小后续升温时的应力释放量及释放速率。(4) Intermediate annealing: Intermediate annealing after the alloy is stretched and deformed has two main purposes. One is to soften the alloy for subsequent re-stretching and deformation; the other is to promote the diffusion of Bi on the grain boundary into the grain. For the alloy of the present invention, the annealing temperature is 500-720°C, the holding time is 0.5-12h, the annealing temperature is lower than 500°C, the alloy softening rate is slow, the dislocation density cannot be quickly reduced, and the annealing efficiency is reduced; the temperature is higher than 720 ℃, the alloy softens fast, but the content of β phase will increase during this annealing process, the hardness of β phase is higher, and the cold working deformation plasticity is worse than α. The annealed material contains a large amount of β phase, which will cause subsequent stretching The amount of pass processing is reduced. In addition, although high temperature annealing can diffuse part of Bi on the grain boundary into the crystal grains, it also makes the crystal grains of the alloy coarse. In order to obtain a good annealed structure, the annealing temperature of this alloy is preferably 600-680°C. The most likely problem in the annealing process of the alloy of the present invention is cracking. On the one hand, it is related to the distribution and particle size of Bi, and on the other hand, the stress release rate during the annealing process of the material also affects it. For ordinary copper-nickel alloy, the rate of stress release has no significant effect on the cracking of the alloy, but when the alloy has large particles of Bi or Bi segregation, the increase of the alloy's stress release rate will increase the cracking tendency of annealing. Therefore, the alloy of the present invention needs to strictly control the annealing system, and the heating rate of annealing is less than 15°C/min, preferably less than 10°C/min. A fast heating rate will easily lead to a faster stress release rate in the early stage of the alloy, and the alloy's annealing cracking tendency will increase. In order to avoid annealing cracking, the alloy of the present invention may further adopt a step annealing method, namely: firstly heat up to 100-350°C at a heating rate less than 15°C/min, hold for 5 to 240 minutes, and then use a heating rate less than 15°C/min Raise the temperature to 500～720℃ for 1～24h. Keep the temperature at a low temperature of 100-350°C for 5 to 240 minutes, preferably 150-300°C, to remove part of the stress in this annealing interval, thereby reducing the amount and rate of stress release during subsequent heating.
(5)成品前退火：本发明合金成品退火可采用与中间退火相同的工艺，该阶段的退火工艺决定合金最终的相比例情况，β相含量的增加，有利于增加合金的切削性能。在某些应用领域要求合金同时具有良好的切削性能和塑性变形性能时，合金需要对β相含量进行控制，如笔头领域，在笔尖的钢珠端存在缩口变形工序，以防止钢珠脱落。β相含量过高，存在缩口变形开裂的风险。(5) Annealing before finishing: The finishing annealing of the alloy of the present invention can use the same process as the intermediate annealing. The annealing process at this stage determines the final phase ratio of the alloy. The increase in the content of β phase is beneficial to increase the cutting performance of the alloy. When alloys are required to have good cutting performance and plastic deformation performance in some application fields, the alloy needs to control the content of β phase. For example, in the pen tip field, there is a necking deformation process at the steel ball end of the pen tip to prevent the steel ball from falling off. If the content of β phase is too high, there is a risk of necking deformation and cracking.
上述易切削锌白铜可应用于家用电器、通讯设备、医用设备、检测和控制仪器、运动器材及制笔行业等。The above-mentioned free-cutting zinc-nickel alloy can be used in household appliances, communication equipment, medical equipment, testing and control instruments, sports equipment and pen-making industries.
与现有技术相比，本发明具有如下优点：Compared with the prior art, the present invention has the following advantages:
(1)通过调控Cu，Ni，Mn，Zn含量关系以使合金在具有良好冷加工变形的基础上，通过适当的热处理工艺获得足够数量的β相，通过调控Ni和Bi的含量关系以使合金具有良好切削性能的同时，大幅减低合金拉伸退火开裂的倾向。(1) By adjusting the content relationship of Cu, Ni, Mn, and Zn so that the alloy has good cold working deformation, a sufficient amount of β phase can be obtained through an appropriate heat treatment process, and the content relationship of Ni and Bi can be adjusted to make the alloy have While good cutting performance, it greatly reduces the tendency of alloy tensile annealing cracking.
(2)利用β相提升合金强度的同时提高切削性能，使Bi在较低的含量情况下达到与铅锌白铜相近的切削性能。(2) The β phase is used to improve the strength of the alloy while improving the cutting performance, so that the cutting performance of Bi is similar to that of lead-zinc cupronickel at a lower content.
(3)抗拉强度≥550MPa，切削性能达到C79860切削性能80％以上。(3) The tensile strength is ≥550MPa, and the cutting performance reaches more than 80% of the C79860 cutting performance.
(4)本发明合金实现了优异的切削性能，适用于各种高精度零部件的高速机械加工。(4) The alloy of the present invention realizes excellent cutting performance and is suitable for high-speed machining of various high-precision parts.
(5)本发明合金可以加工成棒、线等产品，适用于家用电器、通讯设备、医用设备、检测和控制仪器、运动器材、制笔等行业。(5) The alloy of the present invention can be processed into products such as rods and wires, and is suitable for industries such as household appliances, communication equipment, medical equipment, detection and control instruments, sports equipment, and pen-making.
附图说明Description of the drawings
图1为示出实施例11的易切削锌白铜中Bi元素分布的电子显微组织照片；1 is an electron microstructure photograph showing the distribution of Bi element in the free-cutting zinc cupronickel of Example 11;
图2为示出实施例11的易切削锌白铜中β相分布的电子显微组织照片。FIG. 2 is an electron microstructure photograph showing the distribution of β phase in the free-cutting zinc cupronickel of Example 11. FIG.
具体实施方式Detailed ways
以下结合附图实施例对本发明作进一步详细描述。The present invention will be further described in detail below in conjunction with the embodiments of the drawings.
根据表1实施例1～30中锌白铜及比较例1～3的成份进行配料，原料采用全新料，亦可采用新料搭配旧料的方式。熔炼时熔炼炉温度控制在1120℃左右，熔炼完成后进行成分测试，根据成分结果补偿或冲淡，成分合格后倒入保温炉。当保温炉温度恒定在1060℃时，进行全连铸，铸锭规格
Figure PCTCN2020000004-appb-000001
铸锭锯切成400mm长。铸锭挤压温度750℃，保温时间1h，挤压规格
Figure PCTCN2020000004-appb-000002
挤压后采用四次拉伸和退火工艺。一次拉伸(刨皮)采用一道次拉伸，拉伸工艺：
Figure PCTCN2020000004-appb-000003
拉伸
Figure PCTCN2020000004-appb-000004
刨皮至
Figure PCTCN2020000004-appb-000005
一次退火采用罩式炉退火，退火温度600℃，保温时间5h。二次拉伸采用一道次拉伸，拉伸工艺：
Figure PCTCN2020000004-appb-000006
拉伸
Figure PCTCN2020000004-appb-000007
刨皮至
Figure PCTCN2020000004-appb-000008
二次退火采用罩式炉退火，退火温度600℃，保温时间5h。三次拉伸采用一道次拉伸，拉伸工艺：
Figure PCTCN2020000004-appb-000009
拉伸
Figure PCTCN2020000004-appb-000010
三次退火采用罩式炉退火，退火温度600℃，保温时间5h。四次拉伸采用一道次拉伸，拉伸工艺：
Figure PCTCN2020000004-appb-000011
拉伸
Figure PCTCN2020000004-appb-000012
四次退火采用罩式炉退火，退火温度600℃，保温时间5h。成品拉伸：拉伸采用一道次拉伸，拉伸工艺：
Figure PCTCN2020000004-appb-000013
拉伸
Figure PCTCN2020000004-appb-000014
According to the ingredients of the zinc cupronickel in Examples 1-30 in Table 1 and Comparative Examples 1-3, the raw materials are made of new materials, and the method of combining new materials with old materials can also be used. During the smelting, the temperature of the smelting furnace is controlled at about 1120℃. After the smelting is completed, the composition test is performed, and the composition is compensated or diluted according to the composition result. After the composition is qualified, it is poured into the holding furnace. When the temperature of the holding furnace is constant at 1060℃, full continuous casting is carried out, and the ingot specifications are
Figure PCTCN2020000004-appb-000001
The ingot is sawed and cut into 400mm length. Ingot extrusion temperature 750℃, holding time 1h, extrusion specifications
Figure PCTCN2020000004-appb-000002
After extrusion, four stretching and annealing processes are used. One stretch (planing) adopts one stretch, the stretching process:
Figure PCTCN2020000004-appb-000003
Stretch
Figure PCTCN2020000004-appb-000004
Peel to
Figure PCTCN2020000004-appb-000005
One annealing adopts bell furnace annealing, annealing temperature is 600℃, and holding time is 5h. The second stretch adopts one stretch, and the stretch process:
Figure PCTCN2020000004-appb-000006
Stretch
Figure PCTCN2020000004-appb-000007
Peel to
Figure PCTCN2020000004-appb-000008
The second annealing adopts bell-type furnace annealing, the annealing temperature is 600℃, and the holding time is 5h. Three stretches adopt one stretch, the stretching process:
Figure PCTCN2020000004-appb-000009
Stretch
Figure PCTCN2020000004-appb-000010
The third annealing adopts bell furnace annealing, the annealing temperature is 600℃, and the holding time is 5h. The four stretches adopt one stretch, and the stretching process:
Figure PCTCN2020000004-appb-000011
Stretch
Figure PCTCN2020000004-appb-000012
The fourth annealing adopts bell-type furnace annealing, the annealing temperature is 600℃, and the holding time is 5h. Finished product stretching: the stretching adopts one-time stretching, and the stretching process:
Figure PCTCN2020000004-appb-000013
Stretch
Figure PCTCN2020000004-appb-000014
按相关国家及行业标准规定方法检测本发明实施例1～30及比较例1～3锌白铜棒材的抗拉强度、切削性能，试验结果见表1。其中，室温拉伸试验按照《GB/T228.1-2010金属材料拉伸试验第1部分：室温试验方法》在电子万能力学性能试验机上进行。The tensile strength and cutting performance of the zinc-nickel alloy bars of the present invention in Examples 1-30 and Comparative Examples 1-3 were tested according to the methods prescribed by relevant national and industry standards. The test results are shown in Table 1. Among them, the room temperature tensile test is carried out on the electronic universal testing machine in accordance with "GB/T228.1-2010 Metallic Material Tensile Test Part 1: Room Temperature Test Method".
在相同的机械加工条件下，采用切削力实验仪测得各实施例合金的切削力，并由此计算出各实施例合金相对于铅锌白铜C79860的切削性指数，假设其切削性是100％。结果见表1。Under the same machining conditions, the cutting force of each example alloy was measured with a cutting force tester, and the machinability index of each example alloy relative to the lead-zinc cupronickel C79860 was calculated from this, assuming that its machinability was 100% . The results are shown in Table 1.
并对实施例1～30中锌白铜成品的微观组织结构进行分析，结果如表1所示。The microstructure of the finished zinc cupronickel in Examples 1-30 was analyzed, and the results are shown in Table 1.
图1为示出实施例11的易切削锌白铜中Bi元素分布的电子显微组织照片；图2为示出实施例11的易切削锌白铜中β相分布的电子显微组织照片。图1中白色小颗粒为Bi元素颗粒，图2中深色相为β相。FIG. 1 is an electron microstructure photograph showing the distribution of Bi in the free-cutting zinc cupronickel of Example 11; FIG. 2 is an electron microstructure photograph showing the β-phase distribution in the free-cutting zinc cupronickel of Example 11. The small white particles in Figure 1 are Bi element particles, and the dark phase in Figure 2 is the β phase.
其中比较例1成分符合铅锌白铜C79860标准牌号，比较例2符合本发明成分范围，但不含铋；比较例3在本发明合金成分含量范围外。The composition of Comparative Example 1 meets the standard grade of lead-zinc cupronickel C79860, and Comparative Example 2 meets the composition range of the present invention, but does not contain bismuth; Comparative Example 3 is outside the content range of the alloy composition of the present invention.
上述实施例性能测试证明，与C79860以及本发明合金成分以外的对比合金相比，本发明合金具有优异的切削性能、强度及综合性能。The performance test of the above examples proves that compared with C79860 and the comparative alloys other than the alloy composition of the present invention, the alloy of the present invention has excellent cutting performance, strength and comprehensive performance.
Figure PCTCN2020000004-appb-000015
Figure PCTCN2020000004-appb-000015
Figure PCTCN2020000004-appb-000016
Figure PCTCN2020000004-appb-000016

Claims (10)

  1. 一种易切削锌白铜，其特征在于，其重量百分比组成为：Cu：42.5～47.5wt％、Ni：8.0～12.0wt％、Mn：4.0～8.0wt％、Bi：0.05～1.5wt％，余量为Zn和不可避免的杂质。A free-cutting zinc-nickel alloy, characterized in that its weight percentage composition is: Cu: 42.5 to 47.5 wt%, Ni: 8.0 to 12.0 wt%, Mn: 4.0 to 8.0 wt%, Bi: 0.05 to 1.5 wt%, and the remaining The amount is Zn and unavoidable impurities.
  2. 根据权利要求1所述的一种易切削锌白铜，其特征在于，该锌白铜的重量百分比组成中，Cu、Zn、Mn和Ni的重量百分比含量满足：0.30≤(Zn+0.5Mn-1.5Ni)/(Cu+Zn+0.5Mn-1.5Ni)≤0.44。The free-cutting zinc cupronickel according to claim 1, wherein in the weight percentage composition of the zinc cupronickel, the weight percentage content of Cu, Zn, Mn and Ni satisfies: 0.30≤(Zn+0.5Mn-1.5Ni )/(Cu+Zn+0.5Mn-1.5Ni)≤0.44.
  3. 根据权利要求1所述的一种易切削锌白铜，其特征在于，该锌白铜的重量百分比组成中，Ni和Bi的重量百分比含量满足：9≤100(Ni+10Bi)≤23。The free-cutting zinc cupronickel according to claim 1, characterized in that, in the weight percentage composition of the zinc cupronickel, the weight percentage content of Ni and Bi satisfies: 9≤100(Ni+10Bi)≤23.
  4. 根据权利要求1所述的一种易切削锌白铜，其特征在于，该锌白铜横截面的微观组织中单个Bi颗粒的平均面积小于100μm 2。 The free-cutting zinc cupronickel according to claim 1, wherein the average area of a single Bi particle in the microstructure of the cross section of the zinc cupronickel is less than 100 μm 2 .
  5. 根据权利要求1所述的一种易切削锌白铜，其特征在于，该锌白铜横截面的微观组织中α相的平均晶粒尺寸小于90μm，β相的面积含量为10～60％。The free-cutting zinc cupronickel according to claim 1, wherein the average grain size of the α phase in the microstructure of the cross section of the zinc cupronickel is less than 90 μm, and the area content of the β phase is 10-60%.
  6. 根据权利要求1所述的一种易切削锌白铜，其特征在于，该锌白铜的重量百分比组成中还包括以下元素中的至少一种：Co：0.005～2.0wt％、Pb：0.0001～0.2wt％、Te：0.005～1.0wt％、S：0.001～0.2wt％、Se：0.001～0.2wt％、Ca：0.005～0.2wt％、Sb：0.005～1.0wt％、Si：0.005～2.0wt％、P：0.001～0.5wt％、Al：0.005～1.0wt％、Fe：0.005～2.0wt％、Mg：0.005～2.0wt％、B：0.0001～0.2wt％、As：0.0001～0.2wt％、Sn：0.005～2.0wt％、Cr：0.005～1.0wt％、Zr：0.001～0.3wt％、Ti：0.001～0.3wt％、混合稀土：0.0001～0.2wt％。The free-cutting zinc cupronickel according to claim 1, wherein the weight percentage composition of the zinc cupronickel further includes at least one of the following elements: Co: 0.005 to 2.0 wt%, Pb: 0.0001 to 0.2 wt% %, Te: 0.005～1.0wt%, S: 0.001～0.2wt%, Se: 0.001～0.2wt%, Ca: 0.005～0.2wt%, Sb: 0.005～1.0wt%, Si: 0.005～2.0wt%, P: 0.001 to 0.5 wt%, Al: 0.005 to 1.0 wt%, Fe: 0.005 to 2.0 wt%, Mg: 0.005 to 2.0 wt%, B: 0.0001 to 0.2 wt%, As: 0.0001 to 0.2 wt%, Sn: 0.005 to 2.0 wt%, Cr: 0.005 to 1.0 wt%, Zr: 0.001 to 0.3 wt%, Ti: 0.001 to 0.3 wt%, and mixed rare earth: 0.0001 to 0.2 wt%.
  7. 根据权利要求1所述的一种易切削锌白铜，其特征在于，该锌白铜的抗拉强度≥550MPa，切削性能为C79860的80％以上。The free-cutting zinc cupronickel according to claim 1, wherein the tensile strength of the zinc cupronickel is ≥550 MPa, and the cutting performance is more than 80% of that of C79860.
  8. 权利要求1～7中任一项所述的易切削锌白铜的制备方法，其特征在于，其制备工艺流程包括：熔铸→挤压→拉伸→中间退火→拉伸→成品前退火→拉伸→成品。The method for preparing free-cutting zinc-nickel alloy according to any one of claims 1 to 7, characterized in that the preparation process includes: casting→extrusion→stretching→intermediate annealing→stretching→pre-finished annealing→stretching → Finished product.
  9. 根据权利要求8所述的易切削锌白铜的制备方法，其特征在于，所述的中间退火过程为：首先以小于15℃/min的升温速率升温至100～350℃，保温5～240min，然后以小于15℃/min的升温速率升温至500～720℃，保温1～24h。The method for preparing free-cutting zinc cupronickel according to claim 8, characterized in that the intermediate annealing process is as follows: first heat up to 100-350°C at a heating rate of less than 15°C/min, hold for 5 to 240 minutes, and then Raise the temperature to 500～720℃ at a heating rate of less than 15℃/min and keep it for 1～24h.
  10. 权利要求1～7中任一项所述的易切削锌白铜在家用电器、通讯设备、医用设备、检测和控制仪器、运动器材及制笔行业中的应用。The application of the free-cutting zinc cupronickel according to any one of claims 1 to 7 in household appliances, communication equipment, medical equipment, detection and control instruments, sports equipment and pen-making industries.
PCT/CN2020/000004 2019-12-24 2020-01-06 Easy-to-cut zinc-copper-nickel alloy, preparation method therefor and use thereof WO2021128434A1 (en)

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Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112626407A (en) * 2020-12-14 2021-04-09 宁波博威合金材料股份有限公司 Free-cutting zinc white copper and application thereof
CN113637868B (en) * 2021-08-09 2022-04-26 宁波博威合金材料股份有限公司 Copper alloy capable of being riveted and cut, and preparation method and application thereof
CN114438368B (en) * 2022-01-13 2023-02-10 宁波金田铜业(集团)股份有限公司 Lead-free-cutting tin-phosphor bronze alloy and preparation method thereof
CN116555621A (en) * 2023-05-31 2023-08-08 浙江惟精新材料股份有限公司 High-performance white copper with low conductivity and preparation method thereof

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1796582A (en) * 2004-12-21 2006-07-05 中国印钞造币总公司 Nickel silver alloy and processing technique
CN101070573A (en) * 2007-06-27 2007-11-14 北京有色金属研究总院 Bismuth-contained lead-free easy-to-cut zinc-white copper alloy
CN101070931A (en) * 2007-04-23 2007-11-14 中铝洛阳铜业有限公司 Method for preparing large-diameter white copper pipe
CN101787463A (en) * 2010-04-09 2010-07-28 宁波博威合金材料股份有限公司 Environmentally-friendly lead-free free-machining zinc white copper and preparation method thereof
CN101952469A (en) * 2008-03-09 2011-01-19 三菱伸铜株式会社 Silver-white copper alloy and process for producing the same
US20170016097A1 (en) * 2012-03-07 2017-01-19 Wieland-Werke Ag Copper-nickel-zinc alloy containing silicon
CN107151750A (en) * 2017-05-22 2017-09-12 宁波博威合金板带有限公司 A kind of nickel silver alloy and its preparation method and application

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5167726A (en) * 1990-05-15 1992-12-01 At&T Bell Laboratories Machinable lead-free wrought copper-containing alloys
JP3801518B2 (en) * 2002-02-28 2006-07-26 日本伸銅株式会社 Free-cutting copper alloy material
JP3964930B2 (en) * 2004-08-10 2007-08-22 三宝伸銅工業株式会社 Copper-base alloy castings with refined crystal grains
JP5454144B2 (en) * 2007-10-10 2014-03-26 Ｔｏｔｏ株式会社 Lead-free free-cutting brass with excellent castability
US8097208B2 (en) * 2009-08-12 2012-01-17 G&W Electric Company White copper-base alloy
CN105039777B (en) * 2015-05-05 2018-04-24 宁波博威合金材料股份有限公司 A kind of machinable brass alloys and preparation method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1796582A (en) * 2004-12-21 2006-07-05 中国印钞造币总公司 Nickel silver alloy and processing technique
CN101070931A (en) * 2007-04-23 2007-11-14 中铝洛阳铜业有限公司 Method for preparing large-diameter white copper pipe
CN101070573A (en) * 2007-06-27 2007-11-14 北京有色金属研究总院 Bismuth-contained lead-free easy-to-cut zinc-white copper alloy
CN101952469A (en) * 2008-03-09 2011-01-19 三菱伸铜株式会社 Silver-white copper alloy and process for producing the same
CN101787463A (en) * 2010-04-09 2010-07-28 宁波博威合金材料股份有限公司 Environmentally-friendly lead-free free-machining zinc white copper and preparation method thereof
US20170016097A1 (en) * 2012-03-07 2017-01-19 Wieland-Werke Ag Copper-nickel-zinc alloy containing silicon
CN107151750A (en) * 2017-05-22 2017-09-12 宁波博威合金板带有限公司 A kind of nickel silver alloy and its preparation method and application

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