CN110885957A - Process for improving density of tungsten-nickel-copper alloy - Google Patents
Process for improving density of tungsten-nickel-copper alloy Download PDFInfo
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- CN110885957A CN110885957A CN201911325406.6A CN201911325406A CN110885957A CN 110885957 A CN110885957 A CN 110885957A CN 201911325406 A CN201911325406 A CN 201911325406A CN 110885957 A CN110885957 A CN 110885957A
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- 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
- C22F1/18—High-melting or refractory metals or alloys based thereon
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- 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
- C22F1/002—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working by rapid cooling or quenching; cooling agents used therefor
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- 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
- C22F1/02—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working in inert or controlled atmosphere or vacuum
Abstract
The invention discloses a process for improving the density of a tungsten-nickel-copper alloy, which comprises the following steps: firstly, placing the tungsten-nickel-copper alloy in a heating furnace, heating to 1260-1340 ℃ under the condition of introducing hydrogen for protection, and preserving heat for 40-70 min; secondly, rapidly cooling the tungsten-nickel-copper alloy subjected to heat preservation; thirdly, the tungsten-nickel-copper alloy cooled in the step two is heated to 700-900 ℃ and the vacuum degree is 10‑1～10‑2Keeping the temperature for 1-5 h under the condition of Pa, and then cooling along with the furnace. According to the invention, tungsten and copper are fully dissolved mutually by adopting high-temperature heating treatment to form a tightly combined tissue form, the tissue form is kept to room temperature by combining with rapid cooling, and then harmful hydrogen elements introduced into the nickel-copper alloy are removed by combining with vacuum heating treatment, so that the density of the tungsten-nickel-copper alloy is effectively improved, the mechanical property of the tungsten-nickel-copper alloy is improved, the problem of the density incompatibility of the tungsten-nickel-copper alloy is solved, and the waste is avoided.
Description
Technical Field
The invention belongs to the technical field of powder metallurgy, and particularly relates to a process for improving the density of a tungsten-nickel-copper alloy.
Background
The tungsten-nickel-copper alloy is an alloy formed by adding nickel and copper to tungsten, or an alloy formed by adding other metal elements on the basis of the nickel and copper. Typically, the nickel to copper content ratio in a tungsten nickel copper alloy is 3: 2. The tungsten-nickel-copper alloy has no ferromagnetism and relatively good electric and heat conducting properties, and is often applied to occasions with special requirements, such as gyroscope rotors and other devices and instrument parts which need to work under the action of a magnetic field, electric contacts of high-voltage electrical switches, electrodes for electric processing and the like. However, due to poor wettability of copper and tungsten, the density is often out of balance in the production process of the tungsten-nickel-copper alloy. In order to eliminate the phenomenon, most enterprises adopt a repeated sintering method for improvement, but the method can only treat the tungsten-nickel-copper alloy which is seriously under-sintered and has unqualified density so as to meet the density requirement, but has no effect on the tungsten-nickel-copper alloy which is not under-sintered and has unqualified density, so that the sintering density of the tungsten-nickel-copper alloy cannot be improved by secondary sintering, the product is unqualified, and huge economic loss is brought to the enterprises.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a process for increasing the density of tungsten-nickel-copper alloy, aiming at the defects of the prior art. The process adopts high-temperature heating treatment to ensure that tungsten and copper are fully dissolved mutually to form a tightly combined tissue form, combines quick cooling to ensure that the tissue form is kept to room temperature, and then combines vacuum heating treatment to remove harmful hydrogen elements introduced into the nickel-copper alloy, thereby effectively improving the density of the tungsten-nickel-copper alloy, improving the mechanical property of the tungsten-nickel-copper alloy, solving the problem of the density incompatibility of the tungsten-nickel-copper alloy and avoiding waste.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a process for improving the density of a tungsten-nickel-copper alloy is characterized by comprising the following steps:
placing the tungsten-nickel-copper alloy in a heating furnace, heating to 1260-1340 ℃ under the condition of introducing hydrogen for protection, and preserving heat for 40-70 min;
step two, rapidly cooling the tungsten-nickel-copper alloy subjected to heat preservation in the step one;
step three, the tungsten-nickel-copper alloy which is rapidly cooled in the step two is cooled at the temperature of 700-900 ℃ and the vacuum degree of 10-1Pa～10-2Keeping the temperature for 1-5 h under the condition of Pa, and then cooling along with the furnace.
The invention utilizes the property of better intermiscibility of tungsten and copper at high temperature to carry out high-temperature heating treatment on the tungsten-nickel-copper alloy with unqualified density after sintering, so that the tungsten and the copper are fully dissolved mutually to form a tightly combined tissue form, then the tissue form of the tungsten-nickel-copper alloy at high temperature is kept to room temperature by adopting a rapid cooling mode, the phenomenon that the density of the tungsten-nickel-copper alloy is reduced due to the separation of tungsten and copper caused by the poor compatibility of the tungsten and the copper when the temperature is lower in a slow cooling process is avoided, and then the vacuum heating heat preservation treatment is carried out at the temperature below the melting point of the copper, so that harmful hydrogen elements introduced into the tungsten-nickel-copper alloy by hydrogen atmosphere adopted in the high-temperature heat preservation treatment are effectively removed, meanwhile, the re-separation of the tungsten and the internal structure of the tungsten-nickel-copper alloy is prevented from changing. The invention combines high-temperature heating, rapid cooling and vacuum heating treatment, effectively improves the density of the tungsten-nickel-copper alloy, improves the mechanical property of the tungsten-nickel-copper alloy, and solves the problem of the tungsten-nickel-copper alloy with poor density.
The process for improving the density of the tungsten-nickel-copper alloy is characterized in that the heating temperature in the step one is 1320-1340 ℃, and the heat preservation time is 40-60 min.
The process for improving the density of the tungsten-nickel-copper alloy is characterized in that the rapid cooling treatment in the second step is nitrogen gas cooling or water cooling. By adopting the optimized rapid cooling treatment method, the tissue form of the tungsten-nickel-copper alloy at high temperature can be effectively kept to room temperature, the phenomenon of density reduction of the tungsten-nickel-copper alloy caused by separation of tungsten and copper is greatly improved, meanwhile, the bonding strength of tungsten particles and a binding phase at room temperature is improved, and the strength and the elongation of the tungsten-nickel-copper alloy are improved.
The process for improving the density of the tungsten-nickel-copper alloy is characterized in that the temperature in the third step is 800 ℃, and the vacuum degree is 10-1Pa, and the heat preservation time is 3 h.
Compared with the prior art, the invention has the following advantages:
1. the method utilizes the property of better intermiscibility of tungsten and copper at high temperature, adopts high-temperature heating treatment to ensure that tungsten and copper are fully mutually dissolved to form a tightly combined tissue form, combines quick cooling to ensure that the tissue form is kept to room temperature, and then combines vacuum heating treatment to remove harmful hydrogen elements introduced into the nickel-copper alloy, thereby effectively improving the density of the tungsten-nickel-copper alloy, solving the problem of poor density of the tungsten-nickel-copper alloy and avoiding waste.
2. The invention improves the density of the tungsten-nickel-copper alloy, and further improves the mechanical property of the high-specific gravity tungsten-nickel-copper alloy.
3. The invention has short processing period and good processing effect and is suitable for popularization.
The technical solution of the present invention is further described in detail by the accompanying drawings and examples.
Drawings
FIG. 1 is a microstructure of a 90W-Ni-Cu alloy bar in example 1 of the present invention.
FIG. 2 is a microstructure morphology of a 90W-Ni-Cu alloy bar obtained after furnace cooling in example 1 of the present invention.
FIG. 3 is a microstructure of a 93W-Ni-Cu alloy bar in example 2 of the present invention.
FIG. 4 is a microstructure and morphology diagram of a 93W-Ni-Cu alloy bar obtained after furnace cooling in example 2 of the present invention.
FIG. 5 is a microstructure of a 95W-Ni-Cu alloy bar in example 3 of the present invention.
FIG. 6 is a microstructure and morphology diagram of a 95W-Ni-Cu alloy bar obtained after furnace cooling in example 3 of the present invention.
Detailed Description
Example 1
The embodiment comprises the following steps:
step one, placing a 90W-Ni-Cu alloy bar with the size of 20mm multiplied by 200mm (diameter multiplied by length) in a muffle furnace, heating to 1260 ℃ under the condition of introducing hydrogen for protection, and preserving heat for 70 min; the density of the 90W-Ni-Cu alloy bar is 16.6g/cm3；
Step two, taking the 90W-Ni-Cu alloy bar subjected to heat preservation in the step one out of a muffle furnace, and then cooling the bar with water;
step three, cooling the water-cooled 90W-Ni-Cu alloy bar in the step two at the temperature of 700 ℃ and the vacuum degree of 10-2Keeping the temperature for 5 hours under the condition of Pa, and then cooling along with the furnace.
Through detection, the density of the 90W-Ni-Cu alloy bar obtained after furnace cooling in the third step of the embodiment is 17.0g/cm317.05 +/-0.2 g/cm in American Standard AMS T21014 tungsten-based Metal, high Density3The requirements of (1).
Fig. 1 is a microstructure morphology diagram of the 90 w-ni-cu alloy bar in this embodiment, and it can be seen from fig. 1 that tungsten particles in the microstructure of the 90 w-ni-cu alloy bar have been spheroidized but have more pores, which indicates that the sintering degree of the 90 w-ni-cu alloy bar is proper but the density is not proper.
Fig. 2 is a microstructure morphology diagram of the 90 w-ni-cu alloy bar obtained after furnace cooling in the present embodiment, and as can be seen by comparing fig. 2 with fig. 1, holes of tungsten particles in the 90 w-ni-cu alloy bar are significantly reduced, and the density of the 90 w-ni-cu alloy bar is increased, which indicates that the process of the present invention improves the phenomenon of density mismatch in the 90 w-ni-cu alloy, and increases the density of the 90 w-ni-cu alloy.
Example 2
The embodiment comprises the following steps:
step one, placing a 93W-Ni-Cu alloy bar with the size of 30mm multiplied by 100mm (diameter multiplied by length) in a muffle furnace, heating to 1320 ℃ under the condition of introducing hydrogen for protection, and preserving heat for 50 min; the density of the 93W-Ni-Cu alloy bar is 17.3g/cm3；
Step two, taking the heat-insulated 93W-Ni-Cu alloy bar in the step one out of a muffle furnace and then cooling the bar with water;
step three, cooling the 93W-Ni-Cu alloy bar cooled in the step two at the temperature of 800 ℃ and the vacuum degree of 10-1Keeping the temperature for 3 hours under the condition of Pa, and then cooling along with the furnace.
Through detection, the density of the 93W-Ni-Cu alloy bar obtained after furnace cooling in the third step of the embodiment is 17.65g/cm317.05 +/-0.35 g/cm in American Standard AMS T21014 tungsten-based Metal, high Density3The requirements of (1).
Fig. 3 is a microstructure morphology diagram of the 93 w-ni-cu alloy rod in this embodiment, and it can be seen from fig. 3 that the tungsten particles in the microstructure of the 93 w-ni-cu alloy rod are spheroidized but have more pores, which indicates that the sintering degree of the 93 w-ni-cu alloy rod is proper but the density is not proper.
Fig. 4 is a microstructure morphology diagram of the 93 tungsten-nickel-copper alloy bar material obtained after furnace cooling in the embodiment, and as can be seen by comparing fig. 4 with fig. 3, holes of tungsten particles in the 93 tungsten-nickel-copper alloy bar material are obviously reduced, and the density of the 93 tungsten-nickel-copper alloy bar material is improved, which indicates that the process of the present invention improves the phenomenon of density incompatibility in the 93 tungsten-nickel-copper alloy, and improves the density of the 93 tungsten-nickel-copper alloy.
Example 3
The embodiment comprises the following steps:
step one, placing a 95W-Ni-Cu alloy bar with the size of 40mm multiplied by 150mm (diameter multiplied by length) in a muffle furnace, heating to 1340 ℃ under the condition of introducing hydrogen for heat preservation for 40 min; the density of the 95W-Ni-Cu alloy bar is 17.7g/cm3；
Step two, taking the heat-preserved 95W-Ni-Cu alloy bar out of the muffle furnace and then carrying out nitrogen gas cooling;
step three, cooling the water-cooled 95W-Ni-Cu alloy bar in the step two at 900 ℃ and the vacuum degree of 10-2Keeping the temperature for 1h under the condition of Pa, and then cooling along with the furnace.
Through detection, the density of the 95W-Ni-Cu alloy bar obtained after furnace cooling in the third step of the embodiment is 18.05g/cm3Meeting American Standard AMS T21014 tungsten-based goldGenus, high density of 18.05. + -. 0.2g/cm3The requirements of (1).
Fig. 5 is a microstructure morphology diagram of the 95 w-ni-cu alloy bar in this embodiment, and as can be seen from fig. 5, tungsten particles in the microstructure of the 95 w-ni-cu alloy bar have been spheroidized, but have more pores, which indicates that the sintering degree of the 95 w-ni-cu alloy bar is proper, but the density is not proper.
Fig. 6 is a microstructure morphology diagram of the 95 tungsten-nickel-copper alloy bar obtained after furnace cooling in the third step of the present embodiment, and as can be seen by comparing fig. 6 with fig. 5, holes of tungsten particles in the 95 tungsten-nickel-copper alloy bar are significantly reduced, and the density of the 95 tungsten-nickel-copper alloy bar is increased, which indicates that the process of the present invention improves the phenomenon of density mismatch in the 95 tungsten-nickel-copper alloy, and increases the density of the 95 tungsten-nickel-copper alloy.
Example 4
The embodiment comprises the following steps:
step one, placing a 97 tungsten-nickel-copper alloy bar with the size of 40mm multiplied by 150mm (diameter multiplied by length) in a muffle furnace, heating to 1330 ℃ under the condition of introducing hydrogen for protection, and preserving heat for 60 min; the density of the 97 tungsten-nickel-copper alloy bar is 18.15g/cm3；
Step two, taking the 97W-Ni-Cu alloy bar subjected to heat preservation in the step one out of a muffle furnace, and then cooling the bar with water;
step three, cooling the water-cooled 95W-Ni-Cu alloy bar in the step two at 900 ℃ and the vacuum degree of 10-2Keeping the temperature for 2 hours under the condition of Pa, and then cooling along with the furnace.
Through detection, the density of the 95W-Ni-Cu alloy bar obtained after furnace cooling in the third step of the embodiment is 18.35g/cm318.55 +/-0.3 g/cm in American Standard AMS T21014 tungsten-based Metal, high Density3The requirements of (1).
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Any simple modification, change and equivalent changes of the above embodiments according to the technical essence of the invention are still within the protection scope of the technical solution of the invention.
Claims (4)
1. A process for improving the density of a tungsten-nickel-copper alloy is characterized by comprising the following steps:
placing the tungsten-nickel-copper alloy in a heating furnace, heating to 1260-1340 ℃ under the condition of introducing hydrogen for protection, and preserving heat for 40-70 min;
step two, rapidly cooling the tungsten-nickel-copper alloy subjected to heat preservation in the step one;
step three, the tungsten-nickel-copper alloy which is rapidly cooled in the step two is cooled at the temperature of 700-900 ℃ and the vacuum degree of 10-1Pa～10-2Keeping the temperature for 1-5 h under the condition of Pa, and then cooling along with the furnace.
2. The process for improving the density of the tungsten-nickel-copper alloy as claimed in claim 1, wherein the heating temperature in the first step is 1320-1340 ℃ and the holding time is 40-60 min.
3. The process for increasing the density of W-Ni-Cu alloy as claimed in claim 1, wherein the rapid cooling treatment in step two is nitrogen gas cooling or water cooling.
4. The process for increasing the density of the tungsten-nickel-copper alloy as claimed in claim 1, wherein the temperature in the third step is 800 ℃ and the vacuum degree is 10-1Pa, and the heat preservation time is 3 h.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114107714A (en) * | 2021-11-26 | 2022-03-01 | 西安华山钨制品有限公司 | Production process for improving mechanical property of tungsten-nickel-copper alloy |
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| CN102091859A (en) * | 2010-12-28 | 2011-06-15 | 西安华山钨制品有限公司 | High-density tungsten alloy complex part molding process |
| CN104404282A (en) * | 2014-12-02 | 2015-03-11 | 天龙钨钼（天津）有限公司 | Tungsten copper alloy with low tungsten content and preparation method of tungsten copper alloy |
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| JP6106323B1 (en) * | 2016-07-07 | 2017-03-29 | Jfe精密株式会社 | Sintered tungsten-based alloy and method for producing the same |
| CN107988543A (en) * | 2017-11-30 | 2018-05-04 | 西北有色金属研究院 | A kind of high-copper W-Ni-Cu alloy materials and preparation method thereof |
| CN108913973A (en) * | 2018-08-01 | 2018-11-30 | 西安华山钨制品有限公司 | A kind of preparation method of tungsten-nickel-copper alloy paillon |
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2019
- 2019-12-20 CN CN201911325406.6A patent/CN110885957A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101619402A (en) * | 2009-08-06 | 2010-01-06 | 北京天龙钨钼科技有限公司 | Tungsten-nickel-copper alloy and preparation method thereof |
| CN102091859A (en) * | 2010-12-28 | 2011-06-15 | 西安华山钨制品有限公司 | High-density tungsten alloy complex part molding process |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114107714A (en) * | 2021-11-26 | 2022-03-01 | 西安华山钨制品有限公司 | Production process for improving mechanical property of tungsten-nickel-copper alloy |
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Application publication date: 20200317 |