CN113000844A - Preparation method of large-size molybdenum plate - Google Patents
Preparation method of large-size molybdenum plate Download PDFInfo
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- CN113000844A CN113000844A CN201911332211.4A CN201911332211A CN113000844A CN 113000844 A CN113000844 A CN 113000844A CN 201911332211 A CN201911332211 A CN 201911332211A CN 113000844 A CN113000844 A CN 113000844A
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- B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
- B22F5/006—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of flat products, e.g. sheets
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
- B22F3/04—Compacting only by applying fluid pressure, e.g. by cold isostatic pressing [CIP]
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/10—Sintering only
- B22F3/1003—Use of special medium during sintering, e.g. sintering aid
- B22F3/1007—Atmosphere
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- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/18—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces by using pressure rollers
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
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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
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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
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- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
- B22F2003/248—Thermal after-treatment
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- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
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Abstract
The invention discloses a preparation method of a large-size molybdenum plate, which comprises the following steps: firstly, pressing molybdenum powder into a plate blank by adopting a cold isostatic pressing mode, heating and sintering the plate blank in a hydrogen atmosphere, and naturally cooling to obtain a molybdenum plate blank; secondly, cogging and rolling the molybdenum plate blank; thirdly, annealing the molybdenum plate blank after cogging and rolling; fourthly, rolling the annealed molybdenum plate blank twice; fifthly, rolling twice after reversing; sixthly, repeatedly rolling until the required thickness is achieved, and obtaining a large-size molybdenum plate semi-finished product; and seventhly, carrying out vacuum heat treatment on the large-size molybdenum plate semi-finished product to obtain the large-size molybdenum plate. The large-size molybdenum plate prepared by the method has the advantages of flat plate surface, no oxidation, black spots, cracks, peeling, folding and metal and nonmetal pressing defects on the surface, no layering, cracking, loosening and other conditions in the plate, high density and uniform tissue.
Description
Technical Field
The invention belongs to the technical field of molybdenum plate preparation, and particularly relates to a preparation method of a large-size molybdenum plate.
Background
Molybdenum is widely applied to industries such as electronics, medical treatment, glass, ferrous metallurgy and the like due to the specific high melting point, good electric and thermal conductivity and excellent corrosion resistance and ray resistance. Due to the physical, chemical and mechanical properties of molybdenum, the rolling processing of molybdenum is more difficult than the rolling of nonferrous metals such as aluminum, copper, zinc and the like, and the conditions of layering, cracking, loosening and the like are easy to occur in the rolling process, so the development of related application fields is limited.
Disclosure of Invention
The invention aims to solve the technical problem of providing a preparation method of a large-size molybdenum plate aiming at the defects of the prior art. The large-size molybdenum plate prepared by the method has the advantages of flat plate surface, no oxidation, black spots, cracks, peeling, folding and metal nonmetal pressing defects on the surface, no layering, cracking, loosening and other conditions in the plate, high density and uniform tissue.
In order to solve the technical problems, the invention adopts the technical scheme that: the preparation method of the large-size molybdenum plate is characterized by comprising the following steps of:
step one, pressing molybdenum powder into a plate blank with the size of 100mm multiplied by 800mm by adopting a cold isostatic pressing mode, heating and sintering the plate blank in a hydrogen atmosphere, and naturally cooling to obtain a molybdenum plate blank;
step two, cogging and rolling the molybdenum plate blank in the step one; the cogging rolling temperature is 1400-1450 ℃, the heat preservation time is 1-2 h, and the cogging rolling deformation is 25%;
step three, annealing the molybdenum plate blank subjected to cogging rolling in the step two; the temperature of the annealing treatment is 900-1000 ℃, and the heat preservation time is 30-60 min;
step four, performing secondary rolling on the molybdenum plate blank subjected to annealing treatment in the step three;
step five, reversing the molybdenum plate blank rolled in the step four and then performing secondary rolling;
step six, repeating the step four and the step five until the required thickness is reached, and obtaining a large-size molybdenum plate semi-finished product;
and seventhly, carrying out vacuum heat treatment on the large-size molybdenum plate semi-finished product obtained in the step six to obtain the large-size molybdenum plate.
The preparation method of the large-size molybdenum plate is characterized in that the heating and sintering process in the first step is as follows: heating the plate blank to 1000 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then heating to 1500 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then heating to 1760 ℃ at the speed of 3 ℃/min, and preserving heat for 8 h.
The preparation method of the large-size molybdenum plate is characterized in that the temperature of the two-pass rolling in the fourth step is 900-1200 ℃, the total deformation amount of the two-pass rolling is not more than 35%, and the deformation amount of each pass of rolling is 15-20%.
The preparation method of the large-size molybdenum plate is characterized in that the temperature of the two-pass rolling in the step five is 1100-1300 ℃, the total deformation amount of the two-pass rolling is not more than 35%, and the deformation amount of each-pass rolling is 15-20%.
The preparation method of the large-size molybdenum plate is characterized in that the temperature of the vacuum heat treatment in the seventh step is 1100-1400 ℃, and the time is 2-4 hours.
Compared with the prior art, the invention has the following advantages:
the large-size molybdenum plate prepared by the method has the advantages of flat plate surface, no oxidation, black spots, cracks, peeling, folding and metal and nonmetal pressing defects on the surface, no layering, cracking, loosening and other conditions in the plate, high density and uniform tissue.
The technical solution of the present invention is further described in detail by the following examples.
Detailed Description
Example 1
The preparation method of the large-size molybdenum plate comprises the following steps:
step one, pressing molybdenum powder into a plate blank with the size of 100mm multiplied by 800mm by adopting a cold isostatic pressing mode, heating and sintering the plate blank in a hydrogen atmosphere, and naturally cooling to obtain a molybdenum plate blank; the heating sintering process comprises the following steps: heating the plate blank to 1000 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then heating to 1500 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then heating to 1760 ℃ at the speed of 3 ℃/min, and preserving heat for 8 h;
step two, cogging and rolling the molybdenum plate blank in the step one; the cogging rolling temperature is 1400 ℃, the heat preservation time is 2 hours, and the cogging rolling deformation is 25%;
step three, annealing the molybdenum plate blank subjected to cogging rolling in the step two; the temperature of the annealing treatment is 900 ℃, and the heat preservation time is 60 min;
step four, performing secondary rolling on the molybdenum plate blank subjected to annealing treatment in the step three; the temperature of the two-pass rolling is 900 ℃, the total deformation of the two-pass rolling is not more than 35 percent, and the deformation of each-pass rolling is 15 to 20 percent;
step five, reversing the molybdenum plate blank rolled in the step four and then performing secondary rolling; the temperature of the two-pass rolling is 1100 ℃, the total deformation of the two-pass rolling is not more than 35 percent, and the deformation of each-pass rolling is 15 to 20 percent;
step six, repeating the step four and the step five until the required thickness is reached, and obtaining a large-size molybdenum plate semi-finished product;
step seven, carrying out vacuum heat treatment on the large-size molybdenum plate semi-finished product in the step six to obtain a large-size molybdenum plate; the temperature of the vacuum heat treatment is 1100 ℃, and the time is 4 h.
Through detection, the large-size molybdenum plate prepared by the embodiment has the advantages of flat plate surface, no oxidation, black spots, cracks, peeling, folding and metal and nonmetal pressing defects on the surface, no layering, cracking, loosening and other conditions in the plate, high density and uniform tissue.
Example 2
The preparation method of the large-size molybdenum plate comprises the following steps:
step one, pressing molybdenum powder into a plate blank with the size of 100mm multiplied by 800mm by adopting a cold isostatic pressing mode, heating and sintering the plate blank in a hydrogen atmosphere, and naturally cooling to obtain a molybdenum plate blank; the heating sintering process comprises the following steps: heating the plate blank to 1000 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then heating to 1500 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then heating to 1760 ℃ at the speed of 3 ℃/min, and preserving heat for 8 h;
step two, cogging and rolling the molybdenum plate blank in the step one; the cogging rolling temperature is 1450 ℃, the heat preservation time is 1h, and the cogging rolling deformation is 25%;
step three, annealing the molybdenum plate blank subjected to cogging rolling in the step two; the temperature of the annealing treatment is 1000 ℃, and the heat preservation time is 30 min;
step four, performing secondary rolling on the molybdenum plate blank subjected to annealing treatment in the step three; the temperature of the two-pass rolling is 1200 ℃, the total deformation of the two-pass rolling is not more than 35 percent, and the deformation of each-pass rolling is 15 to 20 percent;
step five, reversing the molybdenum plate blank rolled in the step four and then performing secondary rolling; the temperature of the two-pass rolling is 1300 ℃, the total deformation of the two-pass rolling is not more than 35 percent, and the deformation of each-pass rolling is 15 to 20 percent;
step six, repeating the step four and the step five until the required thickness is reached, and obtaining a large-size molybdenum plate semi-finished product;
step seven, carrying out vacuum heat treatment on the large-size molybdenum plate semi-finished product in the step six to obtain a large-size molybdenum plate; the temperature of the vacuum heat treatment is 1400 ℃, and the time is 2 h.
Through detection, the large-size molybdenum plate prepared by the embodiment has the advantages of flat plate surface, no oxidation, black spots, cracks, peeling, folding and metal and nonmetal pressing defects on the surface, no layering, cracking, loosening and other conditions in the plate, high density and uniform tissue.
Example 3
The preparation method of the large-size molybdenum plate comprises the following steps:
step one, pressing molybdenum powder into a plate blank with the size of 100mm multiplied by 800mm by adopting a cold isostatic pressing mode, heating and sintering the plate blank in a hydrogen atmosphere, and naturally cooling to obtain a molybdenum plate blank; the heating sintering process comprises the following steps: heating the plate blank to 1000 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then heating to 1500 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then heating to 1760 ℃ at the speed of 3 ℃/min, and preserving heat for 8 h;
step two, cogging and rolling the molybdenum plate blank in the step one; the cogging rolling temperature is 1420 ℃, the heat preservation time is 1.5h, and the cogging rolling deformation is 25%;
step three, annealing the molybdenum plate blank subjected to cogging rolling in the step two; the temperature of the annealing treatment is 950 ℃, and the heat preservation time is 40 min;
step four, performing secondary rolling on the molybdenum plate blank subjected to annealing treatment in the step three; the temperature of the two-pass rolling is 1000 ℃, the total deformation of the two-pass rolling is not more than 35 percent, and the deformation of each-pass rolling is 15 to 20 percent;
step five, reversing the molybdenum plate blank rolled in the step four and then performing secondary rolling; the temperature of the two-pass rolling is 1200 ℃, the total deformation of the two-pass rolling is not more than 35 percent, and the deformation of each-pass rolling is 15 to 20 percent;
step six, repeating the step four and the step five until the required thickness is reached, and obtaining a large-size molybdenum plate semi-finished product;
step seven, carrying out vacuum heat treatment on the large-size molybdenum plate semi-finished product in the step six to obtain a large-size molybdenum plate; the temperature of the vacuum heat treatment is 1300 ℃, and the time is 3 h.
Through detection, the large-size molybdenum plate prepared by the embodiment has the advantages of flat plate surface, no oxidation, black spots, cracks, peeling, folding and metal and nonmetal pressing defects on the surface, no layering, cracking, loosening and other conditions in the plate, high density and uniform tissue.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.
Claims (5)
1. The preparation method of the large-size molybdenum plate is characterized by comprising the following steps of:
step one, pressing molybdenum powder into a plate blank with the size of 100mm multiplied by 800mm by adopting a cold isostatic pressing mode, heating and sintering the plate blank in a hydrogen atmosphere, and naturally cooling to obtain a molybdenum plate blank;
step two, cogging and rolling the molybdenum plate blank in the step one; the cogging rolling temperature is 1400-1450 ℃, the heat preservation time is 1-2 h, and the cogging rolling deformation is 25%;
step three, annealing the molybdenum plate blank subjected to cogging rolling in the step two; the temperature of the annealing treatment is 900-1000 ℃, and the heat preservation time is 30-60 min;
step four, performing secondary rolling on the molybdenum plate blank subjected to annealing treatment in the step three;
step five, reversing the molybdenum plate blank rolled in the step four and then performing secondary rolling;
step six, repeating the step four and the step five until the required thickness is reached, and obtaining a large-size molybdenum plate semi-finished product;
and seventhly, carrying out vacuum heat treatment on the large-size molybdenum plate semi-finished product obtained in the step six to obtain the large-size molybdenum plate.
2. The method for preparing a large-sized molybdenum plate as claimed in claim 1, wherein the heating and sintering process in the first step is as follows: heating the plate blank to 1000 ℃ at the speed of 5 ℃/min, preserving heat for 2h, then heating to 1500 ℃ at the speed of 5 ℃/min, preserving heat for 3h, then heating to 1760 ℃ at the speed of 3 ℃/min, and preserving heat for 8 h.
3. The method for preparing a large-size molybdenum plate according to claim 1, wherein the temperature of the two rolling passes in the fourth step is 900-1200 ℃, the total deformation of the two rolling passes is not more than 35%, and the deformation of each rolling pass is 15-20%.
4. The method for preparing a large-size molybdenum plate according to claim 1, wherein the temperature of the two-pass rolling in the step five is 1100-1300 ℃, the total deformation of the two-pass rolling is not more than 35%, and the deformation of each pass is 15-20%.
5. The method for preparing a large-sized molybdenum plate as claimed in claim 1, wherein the temperature of the vacuum heat treatment in the seventh step is 1100 ℃ to 1400 ℃ for 2h to 4 h.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911332211.4A CN113000844A (en) | 2019-12-21 | 2019-12-21 | Preparation method of large-size molybdenum plate |
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| CN201911332211.4A CN113000844A (en) | 2019-12-21 | 2019-12-21 | Preparation method of large-size molybdenum plate |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114574821A (en) * | 2022-01-31 | 2022-06-03 | 北京科技大学 | Preparation method of large-size molybdenum target material |
| CN116275050A (en) * | 2023-05-23 | 2023-06-23 | 西安格美金属材料有限公司 | Preparation method of high-strength molybdenum |
-
2019
- 2019-12-21 CN CN201911332211.4A patent/CN113000844A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114574821A (en) * | 2022-01-31 | 2022-06-03 | 北京科技大学 | Preparation method of large-size molybdenum target material |
| CN116275050A (en) * | 2023-05-23 | 2023-06-23 | 西安格美金属材料有限公司 | Preparation method of high-strength molybdenum |
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