MXPA05002640A - Age-hardening copper-base alloy and processing. - Google Patents

Abstract

An age-hardening copper-base alloy and processing method to make a commercially useful strip product for applications requiring high yield strength and moderately high electrical conductivity, in a strip, plate, wire, foil, tube, powder or cast form. The alloys are particularly suited for use in electrical connectors and interconnections. The alloys contain Cu-Ti-X where X is selected from Ni, Fe, Sn, P, Al, Zn, Si, Pb, Be, Mn, Mg, Ag, As, Sb, Zr, B, Cr and Co. and combinations thereof. The alloys offer excellent combinations of yield strength, and electrical conductivity, with excellent stress relaxation resistance. The yield strength is at least of 724 MPa (105 ksi) and the electrical conductivity is at least 50% IACS.

Description

1 COPPER-BASED ALLOY WHICH HARDENES AGING AND AGGREGATE PROCESS FIELD OF THE INVENTION This invention relates to a copper-based alloy that hardens by aging and a process method for producing commercially useful products from this alloy. More particularly, a copper alloy containing 0.35% to 5% by weight of titanium is forged to the final gauge by a process including annealing by solution in process and at least one annealing by aging. The resulting product has an electrical conductivity in excess of 50% EICR and a deformation limit in excess of 724 MPa (105 si). BACKGROUND OF THE INVENTION Throughout this patent application, all compositions are in percent by weight and all mechanical and electrical tests were performed at room temperature (nominally 22 ° C), unless otherwise specified. The word "approximately" implies ± 10% and the word "base" as in copper base, means that the alloy contains at least 50%, by weight, of the specified base element. The terms "laminar" or "laminate" are proposed to include stretching or stretching or any other form of cold reduction, for example, as used in manufacturing Ref. 162519 and process of wire, rod or pipe. Many different types of electrical connectors are formed from copper-based alloys. The important properties of an electrical connector include deformation limit, bending formability, resistance to stress relaxation, modulus of elasticity, resistance to tensile rupture and electrical conductivity. The target values of these properties and the relative importance of the properties are dependent on the proposed application of the products manufactured from the subject copper alloys. The following property descriptions are generic for many proposed applications, but the target values are specific under automotive awning applications. The strain limit is the force at which a material exhibits a specific deviation, typically an equivalent of 0.2%, of stress proportionality and strain. This is indicative of the stress at which the plastic deformation becomes dominant with respect to the elastic deformation. It is desirable that the copper alloys used as connectors have a deformation limit of at least 724 MPa. The relaxation of stress becomes evident when an external effort is applied to a metal strip in service, such as when the strip is loaded after the strip is loaded.

It has been bent into a connector. The metal reacts by developing an opposite and equal internal effort. If the metal is kept in a deformed position, the internal stress will decrease as a function of both time and temperature. This phenomenon occurs due to the conversion of the elastic deformation in the metal to plastic, or permanent deformation, by microplastic flow. The copper-based electrical connectors must maintain a threshold contact force in a coupling member for an extended period for good electrical connection. The stress relaxation reduces the contact force below the threshold that leads to an open circuit. It is desirable that a copper alloy for connector applications maintain at least 95% of the initial stress when exposed to a temperature of 105 ° C for 1000 hours and maintain at least 85% of the initial stress when exposed to a temperature of 150 ° C for 1000 hours. The modulus of elasticity, also known as Young's modulus, is a measure of the stiffness or stiffness of a metal and is the corresponding strain-to-strain ratio in the elastic region. Since the modulus of elasticity is a measure of the stiffness of a material, a high modulus, in the order of 140 GPa (20xl03 ksi) is desirable. The foldability determines the minimum bending radius (RFM) which identifies how severe a bending 4 it can be formed in a metal strip without fracture along the outer radius of the bending. The RFM is an important property for connectors where different shapes will be formed with flexions at various angles. Flexural formability can be expressed as, RFM / t, where t is the thickness of the metal strip. RFM / t is a ratio of the minimum radius of curvature of a mandrel around which the metal strip can be bent without deteriorating the thickness of the strip. The "mandrel" test is specified in the designation E290-92 of ASTM (American Society for Testing and Materials), entitled Standard Test Method for Semi-Guided Bend Test for Ductility of Metallic Materials. It is desirable that the RFM / t be substantially isotropic, a similar value of the "good shape", axis of flexion perpendicular to the winding direction of the metal strip, as well as the "bad shape", axis of flexion parallel to the direction of winding the metal strip. It is desirable that the RFM / t be about 1.5 or less for a 90 ° bend and about 2 or less for a 180 ° bend. Alternatively, the flexural formability for 90 ° bending can be evaluated using a block having a V-shaped recess and a punch with a work surface having a desired radius. In the method of 5"V-shaped block", a strip of the copper alloy in the hardened to be tested is placed between the block and the punch and when the punch is driven into the recess, the desired bending is formed in the strip. Related to the V-shaped block method is the 180 ° "form punch" method in which a punch with a cylindrical work surface is used to form a strip of copper alloy in a 180 ° bend. Both the V-shaped block method and the shape punch method are specified in the ASTM B820-98 designation, entitled Standard Test Method for Bend Test for Formability of Copper Alloy Spring Material. For a given metal sample, both methods give quantifiable foldability results and any method can be used to determine the relative foldability. Tensile rupture strength is a ratio of the maximum load that a strip resists before failure during a tensile test divided by the initial cross-sectional area of the strip. It is desirable that tensile strength is about 760 MPa. The electrical conductivity is expressed in% EICR of (International Standard for Annealed Copper) in which non-alloyed copper is defined as having an electrical conductivity of 100% EICR at 20 ° C. 6 Titanium-based copper-based alloys are described in U.S. Patent Nos. 4,601,879 and 4,612,167, among others. The 4,601,879 patent discloses a copper-based alloy containing 0.25% to 3.0% nickel, 0.25% to 3.0% tin and 0.12% to 1.5% titanium. Exemplary alloys have an electrical conductivity between 48.5% and 51.4% EICR and a deformation limit between 568.8 MPa and 579.2 MPa (82.5 ksi and 84 ksi). The 4,612,167 patent discloses a copper alloy containing 0.8% to 4.0% nickel and 0.2% to 4.0% titanium. Exemplary alloys have an electrical conductivity of 51% EICR and a strain limit of 663.3 MPa and 679.2 MPa (96.2 ksi to 98.5 ksi). AMAX Copper, Inc. (Greenwich, CT) has marketed copper-nickel-titanium alloys that have nominal compositions of Cu-2% Ni-l% Ti and Cu-5% Ni-2.5% Ti. The properties reported for the Cu-2% Ni-l% Ti alloy are formation limit 441.3 MPa-551.6 MPa (64-80 ksi); tensile strength 503.3 MPa - 655.0 MPa (73 - 95 ksi); 9% elongation; and electrical conductivity 50 -60% of EICR. The properties reported for the Cu-5% Ni-2.5% Ti alloy are formation limit 620.6 MPa-689.5 MPa (90 - 100 ksi); tensile strength 744.7 MPa (108 ksi) UTS; 10% elongation; and electrical conductivity 40 - 53% of EICR. 7 Many current and future applications for these copper alloys will require an electrical conductivity of at least 50% EICR and a deformation limit of at least 724 MPa (105 ksi). There remains a need for copper-titanium alloys and processes to manufacture copper-titanium alloys capable of achieving the required levels of electrical conductivity and strength. BRIEF DESCRIPTION OF THE INVENTION In accordance with the invention, a copper-based alloy that hardens by aging and methods for processing this alloy are provided to form a commercially useful product for any application that requires high deformation limit and moderately high electrical conductivity. Typical forms of the product include strip form, plate, wire, sheet, tube, powder or cast. The alloys when processed according to the methods of the invention achieve a deformation limit of at least 724 MPa (105 ksi) and an electrical conductivity of 50% EICR which makes the alloys particularly suitable for use in electrical connectors and interconnections. Alloys that consist essentially, by weight, of 0.35% to 5% of titanium, from 0.001% to 10% of X, where X is selected from Ni, Fe, Sn, P, Al, Zn, Si, Pb, Be, Mn, Mg, Bi, S, Te, Se, Ag, As, Sb, Zr, B, Cr and Co and combinations thereof and the rest is copper and unavoidable impurities. The 8 The alloy has an electrical conductivity of at least 50% EICR and a deformation limit of at least 724 MPa (105 ksi). In a preferred aspect of the invention, the alloy consists essentially of 0.35% to 2.5% of titanium, of 0.5% to 5.0% of nickel, of 0.5% to 0.8% of iron, cobalt and mixtures thereof, of 0.01% a 1.0% magnesium, up to 1% Cr, Zr, Ag and combinations thereof and the rest is copper and unavoidable impurities. These alloys, when beryllium is not present, avoid potentially dangerous health emissions associated with current beryllium-copper alloys, while offering similar combinations of strength and conductivity. BRIEF DESCRIPTION OF THE FIGURES Figure 1 illustrates in flowchart format a first method for processing the copper alloys of the invention. Figure 2 illustrates in flowchart format a second method for processing the copper alloys of the invention. Figure 3 illustrates in flowchart format a third method for processing the copper alloys of the invention. DETAILED DESCRIPTION OF THE INVENTION Copper alloys having a combination of resistance and electrical conductivity, as well as good 9 Formability and stress relieving resistance are in demand for many applications that carry electric current. Two exemplary applications are automotive applications under the awning and multimedia applications (such as computers, DVD players, CD players and the like). For automotive applications, there is a need for copper alloys with good formability, an electrical conductivity of at least 50% EICR and resistance to stress relaxation up to 200 ° C. For multimedia interconnection applications, there is a need for copper alloys with a deformation limit in excess of 724 MPa (105 ksi), an electrical conductivity in excess of 50% EICR. and mechanical stability at ambient service temperatures and slightly higher, as characterized, by resistance to excellent stress relaxation at approximately 100 ° C. The alloy compositions when processed by the methods of this invention surprisingly provide an optimum combination of properties to meet the needs for both automotive and multimedia applications, as well as other electrical and electronic applications. The alloys can provide moderately high strength in combination with high conductivity and moderately high conductivity with very high strength. 10 The alloys of the present invention have compositions containing Cu-Ti-X, where X is selected from Ni, Fe, Sn, P, Al, Zn, Si, Pb, Bi, S, Te, Se, Be, Mn, Mg , Ag, As, Sb, Zr, B, Cr and Co and combinations thereof. The titanium content is 0.35% to 5% and the total sum of the elements "X" is from 0.001% to 10%. The resistance and electrical conductivity are maximized when X is selected from the group consisting of Ni, Fe, Co, Mg, Cr, Zr, Ag and mixtures thereof. Oxygen, sulfur and carbon may be present in the alloys of the invention in amounts typically found in any piece of electrolytic copper alloy (cathode) or remelted copper or copper. Typically, the amount of each of these elements will be in the range of about 2 ppm to about 50 ppm and preferably, each is present in an amount of less than 20 ppm. Other additions that influence the properties of the alloy can also be included. Such additions include those that improve the free workability of the alloy, such as bismuth, lead, tellurium, sulfur and selenium. When added to improve free workability, these additions may be present in an amount of up to 2%. Preferably, the total of the free work additions is between approximately 0.8% and 1.5%. eleven Typical impurities found in copper alloys, particularly in copper alloys formed of scrapped copper or recycled, may be present in an amount of up to about 1%, in total. As a non-exclusive list, such impurities include magnesium, aluminum, silver, silicon, cadmium, bismuth, manganese, cobalt, germanium, arsenic, gold, platinum, palladium, hafnium, zirconium, indium, antimony, chromium, vanadium, and beryllium. Each impurity should be present in an amount of less than 0.35%, and preferably in an amount of less than 0.1%. It should be recognized that some of the impurities cited above, or others, in amounts which overlap the impurity ranges specified above, can have a beneficial effect on the copper alloys of the invention. For example, resistance or punchability can be improved. This invention is proposed to include such low level additions. In a more preferred embodiment of the invention, the titanium content is from 0.35% to 2.5% and in a highly preferred embodiment, the titanium content is from 0.8% to 1.4%. When the titanium is in solution in the copper alloy matrix, the electrical conductivity is severely degraded. Therefore, "X" preferably should be effective to cause the titanium to precipitate from the solution during an annealing by aging. The 12 Suitable elements for "X" to improve such precipitation include Ni, Fe, Sn, P, Al, Si, S, Mg, Cr, Co and combinations of these elements. A preferred addition is nickel. A combination of Ni and Ti provides CuNiTi precipitates and the presence of Fe and Ti provides precipitates of Fe2Ti. Another preferred addition is magnesium. An addition of Mg increases resistance to stress relaxation and softening resistance in tempered and final calibrated products. Mg also provides resistance to softening during annealing heat treatments by aging in process. When present at low levels, additions of Cr, Zr and / or Ag provide increased reinforcement without excessively reducing conductivity. A preferred alloy according to the invention having an improved combination of strain limit, electrical conductivity, resistance to stress relaxation, together with modest levels of collapsibility consists essentially of about 0.5-5.0% nickel about 0.35-2.5% titanium about 0.5 - 0.8% of iron or cobalt about 0.01 - 1.0% magnesium, optionally with up to about 1.0% of one 13 or more than Sn, P, Al, Zn, Si, Pb, Bi, S, Te, Se, Be, Mn, Mg, Ag, As, Sb, Zr, B, Cr and mixtures thereof, and the rest copper and impurities. Preferably the optional elements comprise up to 1% of one or more of Cr, Zr and Ag. The most preferred ranges for this alloy are: about 0.8 - 1.7% nickel about 0.8 - 1.4% titanium | about 0.90 - 1.10% iron, or cobalt about 0.10 - 0.40% magnesium, with up to about 1.0% of one or more than Cr, Zr, Ag or Sn and mixtures thereof, and the rest copper and impurities. In a first embodiment of the invention, the alloy process and composition provide a deformation limit of at least about 793 MPa (115 ksi) and preferably a deformation limit of at least about 827 MPa (120 ksi). For this mode, the conductivity is up to approximately 40% of EICR. In a second embodiment of the invention, the composition and process provide a strain limit of more than about 724 MPa (105 ksi), and preferably up to about 793 MPa (115 ksi). In this second embodiment, the electrical conductivity of the alloy is preferably 14 from about 45% to about 55% EIC. In a third embodiment, the composition and process provide a strain limit of about 552 MPa (80 ksi) to about 690 MPa (100 ksi) and the electrical conductivity is between about 55% and about 65% EICR. Figure 1 illustrates in flowchart format, a process according to a first embodiment of the invention. The alloy of the invention is melted and cast in accordance with conventional practice. The cast alloy is hot rolled 12 from about 750 ° C to about 1000 ° C. After milling to remove the oxide, the alloy is then cold-rolled 14 for a reduction of the cross-sectional area, transverse to the rolling direction ("area reduction") from about 50% to about 99%. The alloy can then be solubilized at an annealing temperature per solution of about 850 to about 1000 ° C from about 10 seconds to about an hour, followed by a quench 18 or rapid cooling to room temperature to obtain equiaxed grains with a size of average grain of approximately 5 and 20 μp ?. Then, the alloy can first be cold-rolled 20 to about 80% reduction in area, preferably from about 30% to about 80% reduction in area. area. The first cold rolling 20 is followed by a first annealing 22 at a temperature from about 400 ° C to about 650 ° C and preferably from about 450 ° C to about 600 ° C for about 1 minute to about 10 hours and preferably about 1 to about 8 hours. The alloy is then subjected to the second cold rolling 24 from about 10% to about 50% area reduction for final gauge. The second cold rolling can be followed by a second annealing 26 from about 150 ° C to about 600 ° C and preferably from about 200 ° C to about 500 ° C from about 15 seconds to about 10 hours. Alternatively, in accordance with another embodiment, the alloy is processed to the final gauge without using a heat treatment of process solubilization. That is, it can be processed for finishing by using lower temperature annealing cycles and intermediate cold working. This alternative process is especially useful to produce a product with higher electrical conductivity levels. Figure 2 illustrates in flowchart representation an alternative process of the invention. The alloy of the invention is melted and cast in accordance with conventional practice. The cast alloy is laminated in 16 hot 12 from about 750 ° C to about 1000 ° C, and then turned off or quickly cooled. After milling to remove the oxide, the hot-rolled alloy is then cold-rolled 14 at an area reduction of about 50% to about 99%. Then, the alloy may be first annealed at an annealing temperature of about 400 ° C to about 650 ° C of about 15 seconds to about 10 hours. The cold rolling and first annealing steps can optionally be repeated, if desired. The alloy is then cold-rolled from about 40% to about 80% area reduction followed by a second annealing 32 from about 400 ° C to about 650 ° C and preferably from about 450 ° C to about 600 ° C. about 1 to about 10 hours. The alloy is then cold-rolled 34 from about 10% to about 50% area reduction for final gauge. This may optionally be followed by a third anneal 26 from about 150 ° C to about 600 ° C and preferably from about 200 ° C to about 500 ° C from about 15 seconds to about 10 hours. A second alternative preferred embodiment of the process of this invention employs an alloy in the preferred composition ranges. This process is capable 17 of producing the alloy of this invention with nominal properties of about 758 MPa (110 ksi) of LD and about 50% of conductivity EICR. With reference to Figure 3, the alloy is cast and cast 10 in accordance with conventional practice. The cast alloy is hot rolled 12 from about 750 ° C to about 1000 ° C. After milling to remove the oxide, the hot-rolled alloy is then cold-rolled 14 at an area reduction of about 50% to about 99%. The alloy is then solubilized at a temperature from about 950 ° C to about 1000 ° C from about 15 seconds to about 1 hour. The alloy is then cold rolled from about 40% to about 60% area reduction and then to first annealing 28 from about 400 ° C to about 650 ° C and preferably 450 ° C to about 600 ° C of about 1 to about 10 hours and preferably from about 1 to about 3 hours. The first annealing 28 is followed by cold rolling 30 from about 40% to about 60% area reduction. The alloy is then subjected to second annealing 32 at a lower temperature than the first annealing 28. The second annealing is at a temperature of about 375 ° C to about 550 ° C of about 1 to about 3 hours. The alloy 18 doubly annealed then cold-rolled 34 to at least about 30% area reduction to a final gauge where a third time can be annealed at a temperature of about 150 ° C to about 600 ° C and preferably about 200 ° C at about 500 ° C from about 1 to about 3 hours. The alloys of the invention and the processes of the invention are better understood with reference to the following examples.

Examples In the examples that follow some of the descriptions, properties and process units are written in abbreviated form. For example, "= inches, EA = cooling with water, a bar marking / = for, RS = annealed for solution, LF = cold rolled or cold reduced, LD = deformation limit, RT = tensile strength, AL = elongation,% EICR = electrical conductivity, RFM / t = minimum bending radius divided by strip thickness, RE = resistance to stress relaxation, Tg = grain size, μt? = Microns or micrometers, com. , recr. = recrystallized, ncr = not completely recrystallized, sec = os = seconds, hrs.oh = hours, MS / m = mega-siemens per meter and ksi = thousands of pounds per square inch.

EXAMPLE 1 Using the process illustrated in Figure 1, a series of 4.5 kg (ten pounds) laboratory ingots with the tested compositions listed in Table 1 were melted in a silica crucible and basted cast in steel molds. After casting, the ingots were 10.16 x 10.16 cm x 4.45 cm (4"X4" xl.75"). After soaking for three hours at 950 ° C, the ingots were hot rolled in three steps at 2.8 cm. 1.1"), were reheated to 950 ° C for ten minutes, and additionally hot rolled in three steps to 1.27 cm (0.50"), followed by water cooling. The resulting hot rolled plates were homogenized by soaking for two. hours at 1000 ° C followed by cooling with water After cutting and grinding to remove the oxide coating, the alloys were cold rolled to 1.27 mm (0.050"). The alloys were then solubilized at a temperature of 1000 ° C of about 20 to 60 seconds, with the exception of alloy J346 which is solubilized at 950 ° C for 60 seconds. After solubilization and cooling, the alloys were cold rolled 50% to 0.64 mm (0.025") and annealed at 550 ° C for 3 hours.The alloys were then cold rolled 50% at 0.32 mm (0.0125"). ) gauge and annealing stress relaxation at 275 ° C for 2 hours and the properties reported in Table 2 were measured. twenty The data in table 2 show that the high values of deformation limit, from 621 MPa to 765 MPa (90 ksi to 111 ksi), and electrical conductivity, from 38.2% of EICR to 63.8% of EICR were obtained. The resistance to stress relaxation obtained was close to the desired value of 95% after 1000 hours at 105 ° C for the J345 and J346 alloys of Cu-Ni-Ti-Fe. The desired value was achieved by the J354 alloy of Cu-Ni-Ti-Mg.

Table 2 Properties of the Anchoring Condition of Relaxation of Efforts for the Alloys Listed in Table 1 % ID EICR LD / RT / EI 90 ° - RFM / t% RE% RE alloy MPa / MPa /% ksi / lcsi /% good shape / 105 ° C 105 ° C cond. bad form 1000 h 3000 h J345 42.9 731/841/12 106/122/2 2.7 / 8.8 90.4 89.5 J346 56.1 669/703/3 97/102/3 1.4 / 2.9 88.2 87.3 J347 34.6 731/807/1 106/117/1 2.7 / 8.8 - - J348 38.2 765/855/4 111/124/4 1.9 / 7.5 - J351 63.8 621/641/1 90/93 / l 1.4 / 2.2 - - J354 47.0 T52 / 793/2 109/115/2 5.0 / 8.8 95.1 93.9 21 Example 2 In accordance with the process illustrated in Figure 2, the alloys of Table 1 were processed as in Example 1 through heat treatment of hot-rolled plate gauge homogenization. In this example, the alloys were processed to the final gauge without a heat treatment of process solubilization. After trimming and grinding to remove the oxide coating, the alloys were cold rolled to 2.54 mm (0.100") and passed to a first anneal by aging at 550 ° C for 3 hours.The alloys were then cold-rolled 70% to 0.76 mm (0.030") and subjected to a second annealing by aging at 525 ° C for 3 hours. The alloys were then cold rolled 50% to 0.38 mm (C.015") gauge and annealing stress relaxation at 275 ° C for 2 hours in which the condition of the properties cited in Table 3 was measured. with the data in table 2, the alloys in this example had a combination of a high deformation limit, from 676 MPa to 738 MPa (98 ksi to 107 ksi), but with higher electrical conductivity of between 49.9% of EICR and 69.7 % EICR The improved resistance to stress relaxation is obtained when either Fe or Mg is added to the base Cu-Ni-Ti alloy The data in Table 3 show that the highest resistance to relaxation Efforts are obtained with an addition of Mg to a Cu-Ni-Ti alloy; Compare J354 alloy with J351 alloy.

Example 3 In accordance with the process illustrated in Figure 1, a series of 4.5 kg (ten pound) laboratory ingots with the tested compositions listed in Table 4 were melted in silica crucibles and basted cast in steel molds. After casting the ingots were 10.16 cm x 10.16 cm x 4.45 cm (4"X 4" x 1.75") After soaking for three hours at 950 ° C, the ingots were hot rolled in three steps to 2.8 cm (1.1") thick, reheated to 950 ° C / ten minutes, and additionally hot rolled in three steps to 1.27 cm (0.50") thick, followed by cooling with water. After trimming and grinding to remove the oxide coating, the alloys are laminated to cold to 1.27 mm (0.050"). Alloys other than J477 were then treated with heat of solution at 1000 ° C for 25 seconds followed by cooling with water to produce a left, fine grain size, controlled in the range of 12 - 24 μp in diameter The J477 alloy was heat treated with solution at 950 ° C / 25 seconds + EA, producing a grain size of 9 μt. All the alloys were then cold-rolled 50% 0.64 mm (0.025") thick and subjected to an annealing by aging at 550 ° C for an effective time to maximize electrical conductivity without unduly softening the matrix. The times at 550 ° C are reported in table 5. The alloys were then cold rolled 50% to 0.32 mm (0.0125") gauge and annealing stress relaxation at 275 ° C for 2 hours in which the condition of the properties of table 5 were measured.The data in table 5 show that, while the basic alloy J477 offers a good combination of properties (634 MPa (92 ksi) of LD and 58.1% of conductivity EICR), the addition of Fe increases the strength of the base alloy (J483 against J477) to 690 MPa (100 ksi) with only a 24 slight reduction in electrical conductivity. In addition, the advantage of Mg addition, while maintaining consistent amounts of i, Ti and Fe, to increase the stress relaxation resistance at 105 ° C is shown by comparing alloy J491 with J481. The Mg advantage is also shown by comparing the properties of the J491 alloy (table 5) compared with those of J345 and J346 in table 2.

Table 5 Properties of the Anchoring Condition of Relaxation of Efforts for the Alloys Listed in Table 4 ID 550 ° C% EIC LD / RT / EI 90 ° -% RE% RE alloy / No. MPa / MPa /% ksi / ksi /% RFM / t 1000 hrs. hrs hrs. 105 ° C 150 ° C J477 3 58.1 634/662/1 92/96 / l 1.1 / 1.8 J481 5 56.6 662/690/4 96/100/4 1.1 / 1.8 92 90 J483 8 54.0 690/717/3 100/104/3 1.8 / 2.2 93 86 J485 8 53.6 696/731/5 101/106/5 0.8 / 2.1 J486 8 52.8 703/731/1 102/106/1 J491 8 55.0 676/703/5 98/102/5 1.4 / 2.4 96 86 25 Example 4 According to the process illustrated in Figure 2, the alloys of Table 4 were processed to the final size without using heat treatment of solubilization in process. After trimming and grinding to remove the oxide coating, the alloys in the hot rolled condition were cold rolled to 0.127 cm (0.050") gauge and passed to a first anneal by aging at a temperature and time as shown in Table 6, effective to maximize electrical conductivity, The alloys were then cold rolled 50% to 0.063 cm (0.025") gauge and subjected to a second annealing by aging at a temperature and time as shown in the table. 6 selected to maximize the conductivity without excessively softening the matrix. The specific annealing applied to each alloy is indicated in Table 6. The alloys were then cold rolled 50% to 0.031 cm (0.0125") caliper and stress relieving annealed at 275 ° C for 2 hours in the which the condition of the properties in table 7 was measured.Using this process, alloys with additions of Fe and Mg provide lower, but still good, strength with higher electrical conductivity and good resistance to stress relaxation.

Example 5 In accordance with the process illustrated in Figure 3, a series of 4.5 kg (ten pound) laboratory ingots with the tested compositions listed in Table 8 were melted in silica crucibles and tilting cast in steel molds. After emptying the ingots were 10.16 cm x 10.16 cm x 4.45 cm 27 ("X4" xl .75") After soaking for three hours at 950 ° C, the ingots were hot rolled in three steps to 2.8 cm (1.1") thick, reheated to 950 ° C for ten minutes, and additionally hot rolled in three steps to 1.27 cm (0.50") gauge, followed by a cooling with water. After trimming and milling to remove the oxide coating, the alloys were cold rolled to 2.54 mm (0.100") thick and treated with solution heat in an oven at 950 ° C for 40 seconds followed by water cooling to produce a fine, fine grain size controlled in the range of 8.0 - 12 μp, then cold rolled 50% to 1.27 mm (0.050") in size and annealed for aging at 565 ° C for 3 hours, designed to maximize conductivity without excessively softening the matrix. The alloys were then cold rolled 50% to 0.64 mm (0.025") gauge and passed to a second anneal by aging 410 ° C for 2 hrs, cold rolled to 0.25 mm (0.010"). This was followed by an annealing stress relaxation of 250 ° C for 2 hrs for which the condition of the properties in table 9 was measured. 28 Comparing the J694 base-line alloy with J698 alloy containing zirconium shows that a small amount of zirconium increases the strain limit without affecting the electrical conductivity. A comparison of J694 alloy with silver-containing J699 alloy shows that a small amount of silver increases both the strain limit and the electrical conductivity. A comparison of the J694 alloy with chromium-containing J700 alloy demonstrates that an addition of a small amount of chromium increases the strain limit slightly with a slight penalty of electrical conductivity. 29 Example 6 In accordance with the process illustrated in Figure 3, a series of 4.5 kg (ten pound) laboratory ingots with the tested compositions listed in Table 10 were melted in silica crucibles and tilting cast in steel molds. After emptying the ingots were 10.16 cm x 10.16 cm x 4.45 cm ("X4" xl.75"). After soaking for three hours at 950 ° C, they were hot rolled in three steps at 2.8 cm (1.1") thick, reheated to 950 ° C for ten minutes, and additionally hot rolled in three steps to 1.27 cm (0.50") thick, followed by cooling with water, after trimming and grinding to remove the oxide coating , the alloys were cold rolled to 2.54 mm (0.100") gauge and heat treated in an oven at 1000 ° C for 25-35 seconds followed by water cooling to produce a recrystallized grain size , fine, controlled in the range of 6 - 12 μ ??. Then they were cold rolled 50% to 1.27 mm (0.050") gauge and subjected to an annealing by aging at 550 - 600 ° C for 3-4 hrs.The alloys were then cold rolled 50% to 0.64 mm (0.025) ") of gauge and again were annealed for aging of 410 - 425 ° C for 2 hrs, followed by cold rolling at 0.25 mm (0.010") and stress relaxation annealing at 250 - 275 ° C per 2 hrs 30 The properties at the final gauge, listed in Table 11, show that a better combination of conductivity and yield strength was obtained with either an addition of Mg (J604 compared to J603) and / or an addition of Zr (J644 compared to cor. J603). Without the addition of Mg, an addition of Cr is not as effective on its own (compare the low resistances of J646 in Table 11 (column D) with the higher resistances of J700 in Table 9). Note also from Table 11 how Mg addition increases the values of strain limit (and tensile strength) over the Mg range: 0, 0.16, 0.25, 0.31% by weight. Addition of Mg to: 703 (758), 710 (772), 745 (772), 745 (800), 758 (814) MPa [102 (110), 103 (112), 108 (116), 110 (118) ksi], respectively, at almost constant conductivity values of approximately 48% EICR.

Table 10 Alloys of Example 6 Number of Composition Analyzed, Weight Identification of Alloy J603 Cu - 1.86 Ni - 1.47 Ti - 0.99 Fe J604 Cu - 1.89 Ni - 1.33 Ti - 0.98 Fe - 0.25 Mg J642 Cu - 1.61 Ni - 1.42 Ti - 1.04 Fe - 0.16 Mg J643 Cu - 1.61 Ni - 1.40 Ti - 1.02 Fe - 0.31 Mg J644 Cu - 1.53 Ni - 1.37 Ti - 0.91 Fe - 0.19 Zr J646 Cu - 1.61 Ni - 1.43 Ti - 0.98 Fe - 0.52 Cr 31 Example 7 This example illustrates how the composition and process influence the deformation and electrical conductivity limit. The J694 and J709 alloys having the compositions cited in Table 12 were processed from 10.16 cm x 10.16 cm x 4.45 cm (4"x4" xl.75") ingots by soaking for 3 hours at 950 ° C and hot rolling 1.27 cm (0.50 in) followed by water cooling, after trimming and grinding to remove the oxides, the alloys were cold rolled to 2.54 mm (0.10 inch) and heat treated at 1000 ° C by 35 ° C. seconds and they cooled 32 with water. The alloys were then cold-rolled to 1.27 mm (0.05 inches), solubilized at 950 ° C for 35 seconds and cooled with water. The additional process is as in Table 13 with the properties cited in Table 14. Table 12 One or more embodiments of the present invention have been described above. However, it will be understood that various modifications can be made without departing from the spirit and scope of the invention. Therefore, other modalities 33 are within the scope of the following claims It is noted that in relation to this date, the best method known to the applicant to practice said invention is that which is clear from the present description of the invention.

Claims (19)

3. 4 CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. Copper-based alloy, characterized in that it consists essentially of weight: from 0.35% to 5% titanium; from 0.001% to 10% of X, where X is selected from Ni, Fe, Sn, P, Al, Zn, Si, Pb, Be, Mn, Mg, Bi, S, Te, Se, Ag, As, Sb, Zr, B, Cr and Co and combinations thereof; and the rest is copper and unavoidable impurities, the alloy has an electrical conductivity of at least 50% EICR and a deformation limit of at least 724 (105 ksi).

2. Copper-based alloy according to claim 1, characterized in that X is selected from the group consisting of Ni, Fe, Co, Mg, Cr, Zr, Ag and combinations thereof.

3. Copper-based alloy according to claim 2, characterized in that it additionally consists essentially of: 0.35% to 2.5% of titanium; from 0.5% to 5.0% nickel; from 0.5% to 0.8% of iron, cobalt and mixtures of the 35 same; from 0.01% to 1.0% magnesium; up to 1% Cr, Zr, Ag and combinations thereof; and the rest is copper and unavoidable impurities.

4. Copper-based alloy according to claim 3, characterized in that it additionally consists essentially of: 0.8% to 1.4% of titanium; from 0.8% to 1.7% nickel; from 0.9% to 1.1% of iron, cobalt and mixtures thereof; from 0.1% to 0.4% magnesium; up to 1% Cr, Zr, Ag and combinations thereof; and the rest is copper and unavoidable impurities.

5. Copper-based alloy characterized by having an improved combination of strain limit, electrical conductivity, resistance to stress relaxation, consisting essentially of, by weight: 0.35-2.5% titanium; 0.5 - 5.0% nickel; 0.5 - 1.5% of iron, cobalt and mixtures thereof; 0.01 - 1.0% magnesium; 36 up to 1% Sn, Cr, Zr, Ag, Sn, P, Al, Zn, Si, Pb, Bi, S, Te, Se, Be, Mn, As, Sb, Zr, B and mixtures thereof; and the rest is copper and unavoidable impurities.

6. Copper-based alloy according to claim 5, characterized in that it contains up to 1% of Cr, Zr, Ag and mixtures thereof.

7. Copper-based alloy according to claim 6, characterized in that it consists essentially of: 0.8-1.4% titanium; 0.8 - 1.7% nickel, - 0.90 - 1.10% iron, or cobalt; 0.10 - 0.40% magnesium; 0.01% to 1.0% Cr, Zr, Ag and mixtures thereof; and the rest is copper and unavoidable impurities.

8. Process for producing a copper-based alloy having an improved combination of strain limit, electrical conductivity and stress relaxation, characterized in that: the casting of a copper-based alloy consisting essentially of 0.35% by weight to 10% titanium, from 0.001% to 6% X, where X is selected from Ni, Fe, Sn, P, Al, Zn, Si, Pb, Be, Mn, Mg, Bi, S, Te, Se, Ag, As, Sb, Zr, B, Cr and Co and combinations thereof and the rest is copper e 37 unavoidable impurities; hot rolling of the alloy from about 750 ° C to about 1000 ° C; the first cold rolling of the alloy at an area reduction of approximately 50% to approximately 97%; the first annealing of the alloy at a temperature from about 850 ° C to about 1000 ° C from about 10 seconds to about an hour, followed by rapid cooling to the environment; the second cold rolling of the alloy up to approximately 80% area reduction; the second annealing of the alloy from about 400 ° C to about 650 ° C from about 1 minute to about 10 hours; the third cold rolling of the alloy from about 10% to about 50% reduction of area to final gauge.

9. Process according to claim 8, characterized in that after the third step of cold rolling, the alloy is annealed at a temperature from about 150 ° C to about 600 ° C from about 15 seconds to about 10 hours.

10. Process according to claim 9, characterized in that the first, second, and third stages of 38 Annealing have effective times and temperatures for the alloy to have a deformation limit of at least 724 MPa (105 ksi) and an electrical conductivity of at least 50% EICR to the final gauge.

11. Process for producing a copper-based alloy having an improved combination of strain limit, electrical conductivity, resistance to stress relaxation, together with modest levels of collapsibility, characterized by: casting a copper-based alloy that consists essentially, by weight, of 0.35% to 10% titanium, from 0.001% to 6% X, where X is selected from Ni, Fe, Sn, P, Al, Zn, Si, Pb, Be, n, Mg , Bi, S, Te, Se, Ag, As, Sb, Zr, B, Cr and Co and combinations thereof and the rest is copper and unavoidable impurities; the hot reduction of the alloy from about 750 ° C to about 1000 ° C; the ratio of one or more cycles comprising cold reduction of the alloy to an area reduction of from about 50% to about 99% and then annealing by aging to an annealing temperature of from about 400 ° C to about 650 ° C. about 15 seconds to about 10 hours; the cold reduction of the alloy from about 40% to about 80% reduction of 39 area; the aging hardening of the annealed alloy from about 400 ° C to about 650 ° C from about 1 to about 10 hours; and the final reduction of the alloy from about 10% to about 50% reduction of area to final gauge.

12. Process in accordance with the claim 11, characterized in that after the final step of cold rolling, the alloy is annealed at a temperature from about 150 ° C to about 600 ° C from about 15 seconds to about 10 hours.

13. Process in accordance with the claim 12, characterized in that the annealing steps have effective times and temperatures for the alloy to have a deformation limit of at least 724 MPa (105 ksi) and an electrical conductivity of at least 50% at final gauge.

14. Process for producing a copper-based alloy having a high deformation limit and moderate resistance, electrical conductivity, characterized in that:. the casting of a copper-based alloy consisting essentially, by weight, of 0.35% to 10% of titanium, from 0.001% to 6% of X, where X is selected from Ni, Fe, Sn, P, Al, Zn , Si, Pb, Be, Mn, Mg, Bi, S, Te, Se, Ag, As, Sb, Zr, B, Cr and Co and combinations thereof and the rest is copper 40 unavoidable impurities; the hot reduction of the alloy from about 750 ° C to about 1000 ° C; the cold reduction of the alloy at an area reduction of from about 50% to about 99%; annealing by solution of the alloy at a temperature from about 950 ° C to about 1000 ° C from about 15 seconds to about an hour, followed by rapid cooling to the environment; the cold reduction of the alloy from approximately 40% to approximately 60% area reduction; the annealing by aging of the alloy at a temperature from about 400 ° C to about 650 ° C from about 1 to about 10 hours; the cold reduction of the alloy from about 40% to about 60% area reduction; the annealing of the alloy a second time at a lower temperature than the first annealing by aging of about 375 ° C to about 550 ° C of about 1 to 41 about 3 hours; and cold reduction to at least about 30% area reduction to a final caliber.

15. Process according to claim 14, characterized in that after the final step of cold rolling, the alloy is annealed at a temperature from about 150 ° C to about 600 ° C from about 15 seconds to about 10 hours.

16. Process according to claim 15, characterized in that the first, second, and third stages of annealing have effective times and temperatures for the alloy to have a deformation limit of at least 724 MPa (105 ksi) and an electrical conductivity of at least 50% of EICR to caliber. final .

17. Process for producing a copper-based alloy having high deformation limit and moderate strength, electrical conductivity, characterized in that: the casting of a copper-based alloy consisting essentially of 0.35% to 10% by weight of titanium, from 0.001% to 6% of X, where X is selected from Ni, Fe, Sn, P, Al, Zn, Si, Pb, Be, Mn, Mg, Bi, S, Te, 42 Se, Ag, As, Sb, Zr, B, Cr and Co and combinations thereof and the rest is copper and unavoidable impurities; hot rolling of the alloy from about 750 ° C to about 1000 ° C; the cold rolling of the alloy at an area reduction of from about 50% to about 99%; annealing by solution of the alloy at a temperature from about 950 ° C to about 1000 ° C from about 10 seconds to about an hour, followed by rapid cooling to the environment; the cold rolling of the alloy from about 40% to about 60% area reduction? annealing by aging the alloy at a temperature from about 500 ° C to about 575 ° C from about 15 seconds to about 10 hours or at a temperature from about 425 to about 475 ° C for about 2.5 to about 3.5 hours; the cold rolling of the alloy from about 40% to about 60% area reduction; the annealing by aging of alloy 43 a second time at a temperature of from about 500 ° C to about 550 ° C from about 1 to about 4 hours; and the final laminate to at least about 30% area reduction to a final gauge.

18. Process according to claim 17, characterized in that after the final step of cold rolling, the alloy is annealed at a temperature from about 150 ° C to about 600 ° C from about 15 seconds to about 10 hours. Process according to claim 18, characterized in that the annealing steps have effective times and temperatures for the alloy to have a deformation limit of at least 724 MPa (105 ksi) and an electrical conductivity of at least 50% at caliber final.