CN110695367A - Preparation method of molybdenum-tungsten alloy powder - Google Patents
Preparation method of molybdenum-tungsten alloy powder Download PDFInfo
- Publication number
- CN110695367A CN110695367A CN201911036941.XA CN201911036941A CN110695367A CN 110695367 A CN110695367 A CN 110695367A CN 201911036941 A CN201911036941 A CN 201911036941A CN 110695367 A CN110695367 A CN 110695367A
- Authority
- CN
- China
- Prior art keywords
- molybdenum
- tungsten
- temperature
- composite oxide
- boat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
- B22F9/22—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds using gaseous reductors
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
Abstract
The invention discloses a preparation method of molybdenum-tungsten alloy powder, which comprises the following steps: firstly, adding molybdenum trioxide and tungstic acid into diluted ammonia water for dissolving to obtain a mixed solution of ammonium molybdate and ammonium tungstate; secondly, spray drying the mixed solution of ammonium molybdate and ammonium tungstate to obtain a molybdenum-tungsten composite oxide precursor; thirdly, roasting and decomposing the molybdenum-tungsten composite oxide precursor under the temperature gradient condition to obtain the molybdenum-tungsten composite oxide; fourthly, carrying out primary reduction on the molybdenum-tungsten composite oxide under the hydrogen condition to obtain molybdenum-tungsten low-valence oxide; and fifthly, carrying out two-stage reduction on the molybdenum-tungsten low-valence oxide under the condition of hydrogen to obtain molybdenum-tungsten alloy powder. According to the invention, molybdenum-tungsten alloy powder is prepared by fully mixing molybdate ions and tungstate ions, and then roasting and reducing, so that the molybdenum particles and the tungsten particles have small volume and mass difference and large mixing power, the uniformity of the molybdenum-tungsten alloy powder is improved, and the problem of insufficient uniformity caused by mechanical mixing of the molybdenum powder and the tungsten powder is solved.
Description
Technical Field
The invention belongs to the technical field of powder material preparation, and particularly relates to a preparation method of molybdenum-tungsten alloy powder.
Background
Molybdenum and tungsten are elements in the fifth and sixth periods of the sixth subgroup in the periodic table, belong to refractory metals, and have high similarity in physical and chemical properties. Molybdenum and tungsten are mainly applied to the fields of metal products, catalysts for petroleum smelting, metal targets for the electronic industry and the like in industrial production.
The molybdenum-tungsten alloy powder is a raw material for preparing the molybdenum-tungsten alloy, and the uniformity of the molybdenum-tungsten alloy powder directly influences the high-temperature strength, the service life and other properties of the molybdenum-tungsten alloy. The traditional preparation method of the molybdenum-tungsten alloy powder is a mechanical mixing method and comprises the following steps: firstly, mechanically mixing molybdenum powder and tungsten powder according to a proportion; secondly, pressing the mixture into a blank by a mechanical press or an isostatic press; thirdly, sintering the mixture into a molybdenum-tungsten alloy billet in a high-temperature sintering furnace filled with hydrogen. The raw materials adopted by the method are molybdenum powder and tungsten powder, the molybdenum powder and the tungsten powder have certain particle volume and quality, and even if the mechanical mixing is sufficient, the particles are always uneven, so that the uniformity of the molybdenum-tungsten alloy powder is poor.
Therefore, it is necessary to develop a method for preparing molybdenum-tungsten alloy powder, which has sufficient tungsten-molybdenum interdiffusion power, minimum volume and mass of molybdenum particles and tungsten particles, and eliminates the problem of insufficient uniformity caused by mechanical mixing of molybdenum powder and tungsten powder.
Disclosure of Invention
The invention aims to solve the technical problem of providing a preparation method of molybdenum-tungsten alloy powder aiming at the defects of the prior art. According to the method, molybdenum-tungsten alloy powder is prepared by fully mixing molybdate ions and tungstate ions and then performing subsequent roasting and reduction processes, so that the molybdenum particles and the tungsten particles have small volume and mass difference and large mixing power, the uniformity of the molybdenum-tungsten alloy powder is improved, and the problem of insufficient uniformity caused by mechanical mixing of the molybdenum powder and the tungsten powder is solved.
In order to solve the technical problems, the invention adopts the technical scheme that: the preparation method of the molybdenum-tungsten alloy powder is characterized by comprising the following steps of:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: uniformly mixing deionized water and ammonia water to obtain diluted ammonia water, adding molybdenum trioxide and tungstic acid into the diluted ammonia water, stirring and dissolving, and performing solid-liquid separation to obtain a supernatant which is a mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor;
step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a material boat, then putting the material boat into air, and roasting and decomposing the material boat under the temperature gradient condition to obtain molybdenum-tungsten composite oxide;
step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat, and carrying out first-stage reduction under the condition of hydrogen to obtain molybdenum-tungsten low-valence oxide;
step five, second-stage reduction: and (4) putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat, and carrying out second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder.
The method comprises the steps of adopting tungstic acid and molybdenum trioxide as a tungsten source and a molybdenum source respectively, forming a uniform and stable mixed solution of ammonium molybdate and ammonium tungstate after ammonia water dissolution reaction, then removing water and ammonia in the mixed solution of ammonium tungstate and ammonium molybdate by adopting a spray drying mode to obtain a molybdenum-tungsten composite oxide precursor, converting the molybdenum-tungsten composite oxide precursor into a molybdenum-tungsten composite oxide through roasting, decomposition, dehydration and deamination, sequentially carrying out two-stage hydrogen reduction on the molybdenum-tungsten composite oxide, reducing molybdenum trioxide in the molybdenum-tungsten composite oxide into molybdenum dioxide, reducing tungsten trioxide into tungsten dioxide to obtain a molybdenum-tungsten low-valence oxide, and reducing the molybdenum-tungsten low-valence oxide into molybdenum-tungsten alloy powder. According to the invention, through fully mixing ammonium molybdate and ammonium tungstate solutions, diffusion motion mixing of molybdate ions and tungstate ions at the grade is realized, and then through subsequent roasting and reduction processes, the volume and mass difference between molybdenum particles and tungsten particles is small, the mixing power is large, uniform mixing of molybdenum powder and tungsten powder is realized, the uniformity of molybdenum-tungsten alloy powder is improved, and the problem of insufficient uniformity caused by mechanical mixing of molybdenum powder and tungsten powder is solved.
The preparation method of the molybdenum-tungsten alloy powder is characterized in that the mass ratio of the tungstic acid to the molybdenum trioxide in the step one is 1 (1-4). The mass ratio of the raw materials can ensure that the mass content of tungsten in the molybdenum-tungsten alloy powder is 20-52 percent, and the requirements of most practical use are met.
The preparation method of the molybdenum-tungsten alloy powder is characterized in that in the step one, the mass ratio of ammonia water to deionized water is 1 (1-2), and the mass ratio of molybdenum trioxide to deionized water is 1 (1-3); the temperature of stirring and dissolving is 55-75 ℃, the speed is 280-500 r/min, and the time is 1-1.5 h. The mass ratio and the stirring and dissolving conditions ensure that the molybdenum trioxide and the tungstic acid can be completely dissolved to form a solution.
The preparation method of the molybdenum-tungsten alloy powder is characterized in that in the spray drying process in the step two, the temperature of an air inlet of a spray drying tower is 205-255 ℃, the temperature of an air outlet is 110-155 ℃, and the rotating speed of an atomizer of the spray drying tower is 0.8 multiplied by 104r/min～2.0×104r/min. On the upper partThe technological parameters of the spray drying ensure that the water and part of ammonia in the mixed solution of ammonium molybdate and ammonium tungstate are effectively removed after the mixed solution of ammonium molybdate and ammonium tungstate is subjected to spray drying, the prepared molybdenum-tungsten composite oxide precursor powder has low water content, does not adhere to the inner wall of spray drying equipment, and ensures the smooth operation of spray drying.
The preparation method of the molybdenum-tungsten alloy powder is characterized in that the material boat in the third step is a stainless steel material boat. The stainless steel boat is not easy to react with oxygen in the air, and is not easy to react with molybdenum-tungsten composite oxide precursors and molybdenum trioxide and tungsten oxide in molybdenum-tungsten composite oxides as roasting decomposition products, and is suitable for a roasting process.
The preparation method of the molybdenum-tungsten alloy powder is characterized in that the thickness of the molybdenum-tungsten composite oxide precursor put into the stainless steel material boat in the step three is 0.8 cm-1.2 cm, and the roasting decomposition process under the temperature gradient condition comprises the following steps: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 3.5m3/h～5.6m3H is used as the reference value. The thickness, the temperature gradient condition, the boat pushing speed and the air flow of the preferred molybdenum-tungsten composite oxide precursor ensure the thorough volatilization of water and ammonia in the molybdenum-tungsten composite oxide precursor.
The preparation method of the molybdenum-tungsten alloy powder is characterized in that the thickness of the molybdenum-tungsten composite oxide put into the molybdenum boat in the fourth step is 0.5 cm-1.1 cm, the first-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at the temperature of 400-450 ℃, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage of reduction process is 2 boats/40 min, and the hydrogen flow rate is 0.5m3/h～0.7m3H is used as the reference value. Thickness and temperature gradient of the above-described preferred molybdenum-tungsten composite oxideThe temperature condition, the boat pushing speed and the hydrogen flow further ensure that the molybdenum-tungsten composite oxide is reduced into molybdenum-tungsten low-valence oxide, and molybdenum trioxide is reduced into molybdenum dioxide, tungsten trioxide is reduced into tungsten dioxide or other low-valence molybdenum-tungsten oxides.
The preparation method of the molybdenum-tungsten alloy powder is characterized in that the thickness of the molybdenum-tungsten low-valence oxide put into the molybdenum boat in the step five is 0.5 cm-1.1 cm, the two-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at 850-880 ℃, then preserving heat at a temperature higher than 880 ℃ and not higher than 920 ℃, preserving heat at a temperature higher than 920 ℃ and not higher than 950 ℃, and finally preserving heat at a temperature higher than 880 ℃ and not higher than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.7m3/h～0.9m3H is used as the reference value. The thickness, temperature gradient condition, boat pushing speed and hydrogen flow of the preferred molybdenum-tungsten composite oxide further ensure that the molybdenum-tungsten low-valence oxides are reduced into molybdenum-tungsten alloy powder, so that molybdenum dioxide is reduced into molybdenum powder and tungsten dioxide is reduced into tungsten powder, or other low-valence molybdenum-tungsten oxides are reduced into molybdenum powder and tungsten powder.
Compared with the prior art, the invention has the following advantages:
1. the invention adopts tungstic acid and molybdenum trioxide as a tungsten source and a molybdenum source respectively, and forms uniform and stable ammonium tungstate and ammonium molybdate mixed solution after ammonia water dissolution, thereby realizing the full mixing of molybdate ions and tungstate ions, and then leading the volume and mass difference between molybdenum particles and tungsten particles to be small and the mixing power to be large through the subsequent roasting and reduction processes, improving the uniformity of molybdenum-tungsten alloy powder and eliminating the problem of insufficient uniformity caused by mechanical mixing of molybdenum powder and tungsten powder.
2. The tungsten powder mass content in the molybdenum-tungsten alloy powder prepared by the method can reach 20-52%, and the tungsten powder is uniformly distributed in the molybdenum-tungsten alloy powder, so that the use requirement of the molybdenum-tungsten alloy powder is met.
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Drawings
FIG. 1 is a process flow diagram for preparing molybdenum-tungsten alloy powder according to the present invention.
Detailed Description
As shown in figure 1, the process for preparing the molybdenum-tungsten alloy powder comprises the following steps: firstly, tungstic acid and molybdenum trioxide are dissolved in diluted ammonia water to obtain a mixed solution of ammonium tungstate and ammonium molybdate, so that the tungsten tungstate ions and the molybdenum molybdate ions are mixed in a diffusion motion mode at the grade, then, the molybdenum-tungsten composite oxide precursor is prepared by spray drying dehydration and deamination, the molybdenum-tungsten composite oxide precursor is decomposed by roasting to obtain a molybdenum-tungsten composite oxide, the molybdenum-tungsten composite oxide is sequentially subjected to one-stage reduction to obtain a valence-state molybdenum-tungsten oxide, and the molybdenum-tungsten composite oxide is subjected to two-stage reduction to obtain molybdenum-tungsten alloy powder.
The mass concentration of the ammonia water used in examples 1 to 7 of the present invention is 25% to 28%.
Example 1
The embodiment comprises the following steps:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: 800.15g of deionized water and 400.26g of ammonia water are mixed uniformly to obtain diluted ammonia water, then 267.21g of molybdenum trioxide and 67.18g of tungstic acid are added into the diluted ammonia water under the conditions that the stirring speed is 280r/min and the temperature is 55 ℃, the mixture is stirred and dissolved for 1 hour, and the supernatant obtained after solid-liquid separation is the mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor; in the spray drying process, the temperature of an air inlet of the spray drying tower is 251 ℃, the temperature of an air outlet of the spray drying tower is 154 ℃, and the rotating speed of an atomizer of the spray drying tower is 1.9 multiplied by 104r/min；
Step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a stainless steel material boat until the thickness is 0.8cm, then putting the stainless steel material boat into air, and roasting and decomposing the stainless steel material boat under the condition of temperature gradient to obtain molybdenum-tungsten composite oxide; the roasting decomposition is carried out under the temperature gradient conditionThe process is as follows: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 3.5m3/h；
Step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat until the thickness is 0.5cm, and carrying out first-stage reduction under the condition of hydrogen to obtain molybdenum-tungsten low-valence oxide; the first-stage reduction is carried out under the condition of temperature gradient, and the specific process is as follows: firstly, preserving heat at the temperature of 400-450 ℃, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.5m3/h；
Step five, second-stage reduction: putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat until the thickness is 0.5cm, and performing second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder; the second-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at 850-880 ℃, then preserving heat at a temperature higher than 880 ℃ and not higher than 920 ℃, preserving heat at a temperature higher than 920 ℃ and not higher than 950 ℃, and finally preserving heat at a temperature higher than 880 ℃ and not higher than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.7m3/h。
By calculation, the theoretical value of the tungsten mass content in the molybdenum-tungsten alloy powder prepared in the embodiment is 21.72%.
Example 2
The embodiment comprises the following steps:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: 1500.36g of deionized water and 1499.98g of ammonia water are mixed uniformly to obtain diluted ammonia water, then 751.33g of molybdenum trioxide and 750.55g of tungstic acid are added into the diluted ammonia water under the conditions of stirring speed of 500r/min and temperature of 75 ℃, stirred and dissolved for 1.5h, and the supernatant obtained after solid-liquid separation is the mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor; in the spray drying process, the temperature of an air inlet of the spray drying tower is 205 ℃, the temperature of an air outlet of the spray drying tower is 110 ℃, and the rotating speed of an atomizer of the spray drying tower is 0.8 multiplied by 104r/min；
Step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a stainless steel material boat until the thickness is 1.2cm, then putting the stainless steel material boat into the air, and roasting and decomposing the molybdenum-tungsten composite oxide precursor under the condition of temperature gradient to obtain a molybdenum-tungsten composite oxide; the roasting decomposition process under the temperature gradient condition comprises the following steps: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 5.6m3/h；
Step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat until the thickness is 1.1cm, and carrying out first-stage reduction under the hydrogen condition to obtain molybdenum-tungsten low-valence oxide; the first-stage reduction is carried out under the condition of temperature gradient, and the specific process is as follows: firstly, preserving heat at the temperature of 400-450 ℃, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.7m3/h；
Step five, second-stage reduction: putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat until the thickness is 1.1cm, and performing second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder; the second-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, the temperature is kept at 850-880 ℃, then the temperature is kept at a temperature which is higher than 880 ℃ and not higher than 920 ℃, then the temperature is kept at a temperature which is higher than 920 ℃ and not higher than 950 ℃, and finally the temperature is kept at a temperature which is higher than 880 ℃ and not higher than 950 DEG CPreserving heat at a temperature; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.9m3/h。
By calculation, the theoretical value of the mass content of tungsten in the molybdenum-tungsten alloy powder prepared in the embodiment is 52.44%.
Example 3
The embodiment comprises the following steps:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: 1200.65g of deionized water and 800.19g of ammonia water are mixed uniformly to obtain diluted ammonia water, then 500.91g of molybdenum trioxide and 300.12g of tungstic acid are added into the diluted ammonia water under the conditions of stirring speed of 300r/min and temperature of 60 ℃, stirred and dissolved for 1.5h, and the supernatant obtained after solid-liquid separation is the mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor; in the spray drying process, the temperature of an air inlet of the spray drying tower is 235 ℃, the temperature of an air outlet is 151 ℃, and the rotating speed of an atomizer of the spray drying tower is 1.5 multiplied by 104r/min；
Step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a stainless steel material boat until the thickness is 1.0cm, then putting the stainless steel material boat into the air, and roasting and decomposing the molybdenum-tungsten composite oxide precursor under the condition of temperature gradient to obtain a molybdenum-tungsten composite oxide; the roasting decomposition process under the temperature gradient condition comprises the following steps: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 4.2m3/h；
Step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat until the thickness is 0.6cm, and carrying out first-stage reduction under the condition of hydrogen to obtain molybdenum-tungsten low-valence oxide; the first-stage reduction is carried out under the condition of temperature gradient, and the specific process is as follows: firstly at 400-450 deg.CPreserving heat at the temperature, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.7m3/h；
Step five, second-stage reduction: putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat until the thickness is 1.0cm, and performing second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder; the second-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at 850-880 ℃, then preserving heat at a temperature higher than 880 ℃ and not higher than 920 ℃, preserving heat at a temperature higher than 920 ℃ and not higher than 950 ℃, and finally preserving heat at a temperature higher than 880 ℃ and not higher than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.8m3/h。
By calculation, the theoretical value of the mass content of tungsten in the molybdenum-tungsten alloy powder prepared in the embodiment is 39.81%.
Example 4
The embodiment comprises the following steps:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: 1000.55g of deionized water and 999.89g of ammonia water are mixed uniformly to obtain diluted ammonia water, then 450.02g of molybdenum trioxide and 350.83g of tungstic acid are added into the diluted ammonia water under the conditions of stirring speed of 400r/min and temperature of 69 ℃, stirred and dissolved for 1.5h, and the supernatant obtained after solid-liquid separation is the mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor; in the spray drying process, the temperature of an air inlet of the spray drying tower is 220 ℃, the temperature of an air outlet is 125 ℃, and the rotating speed of an atomizer of the spray drying tower is 1.8 multiplied by 104r/min；
Step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a stainless steel boat until the thickness is 1.2cm,then placing the mixture in air, and roasting and decomposing the mixture under the condition of temperature gradient to obtain molybdenum-tungsten composite oxide; the roasting decomposition process under the temperature gradient condition comprises the following steps: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 4.8m3/h；
Step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat until the thickness is 0.8cm, and carrying out first-stage reduction under the condition of hydrogen to obtain molybdenum-tungsten low-valence oxide; the first-stage reduction is carried out under the condition of temperature gradient, and the specific process is as follows: firstly, preserving heat at the temperature of 400-450 ℃, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.7m3/h；
Step five, second-stage reduction: putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat until the thickness is 0.9cm, and performing second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder; the second-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at 850-880 ℃, then preserving heat at a temperature higher than 880 ℃ and not higher than 920 ℃, preserving heat at a temperature higher than 920 ℃ and not higher than 950 ℃, and finally preserving heat at a temperature higher than 880 ℃ and not higher than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.9m3/h。
By calculation, the theoretical value of the mass content of tungsten in the molybdenum-tungsten alloy powder prepared in the embodiment is 46.18%.
Example 5
The embodiment comprises the following steps:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: 1300.21g of deionized water and 1200.77g of ammonia water are mixed uniformly to obtain diluted ammonia water, then 825.16g of molybdenum trioxide and 250.12g of tungstic acid are added into the diluted ammonia water under the conditions of stirring speed of 500r/min and temperature of 71 ℃, stirred and dissolved for 1.5h, and the supernatant obtained after solid-liquid separation is the mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor; in the spray drying process, the temperature of an air inlet of the spray drying tower is 210 ℃, the temperature of an air outlet is 135 ℃, and the rotating speed of an atomizer of the spray drying tower is 1.7 multiplied by 104r/min；
Step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a stainless steel material boat until the thickness is 1.1cm, then putting the stainless steel material boat into air, and roasting and decomposing the stainless steel material boat under the condition of temperature gradient to obtain molybdenum-tungsten composite oxide; the roasting decomposition process under the temperature gradient condition comprises the following steps: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 4.2m3/h；
Step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat until the thickness is 0.9cm, and carrying out first-stage reduction under the condition of hydrogen to obtain molybdenum-tungsten low-valence oxide; the first-stage reduction is carried out under the condition of temperature gradient, and the specific process is as follows: firstly, preserving heat at the temperature of 400-450 ℃, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.7m3/h；
Step five, second-stage reduction: putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat until the thickness is 1.0cm, and performing second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder; the second-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, the temperature is kept at 850-880 ℃, and then the temperature is sent to be more than 8 DEG CPreserving heat at a temperature of 80 ℃ to no more than 920 ℃, then preserving heat at a temperature of more than 920 ℃ to no more than 950 ℃, and finally preserving heat at a temperature of more than 880 ℃ to no more than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.9m3/h。
By calculation, the theoretical value of the mass content of tungsten in the molybdenum-tungsten alloy powder prepared in the embodiment is 25.07%.
Example 6
The embodiment comprises the following steps:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: 1460.26g of deionized water and 1355.39g of ammonia water are mixed uniformly to obtain diluted ammonia water, then 486.81g of molybdenum trioxide and 243.98g of tungstic acid are added into the diluted ammonia water under the conditions of stirring speed of 500r/min and temperature of 75 ℃, stirred and dissolved for 1.3h, and the supernatant obtained after solid-liquid separation is the mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor; in the spray drying process, the temperature of an air inlet of the spray drying tower is 188 ℃, the temperature of an air outlet is 126 ℃, and the rotating speed of an atomizer of the spray drying tower is 2.0 multiplied by 104r/min；
Step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a stainless steel material boat until the thickness is 1.0cm, then putting the stainless steel material boat into the air, and roasting and decomposing the molybdenum-tungsten composite oxide precursor under the condition of temperature gradient to obtain a molybdenum-tungsten composite oxide; the roasting decomposition process under the temperature gradient condition comprises the following steps: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 4.2m3/h；
Step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat until the thickness is 0.9cm, and putting the molybdenum-tungsten composite oxide into a hydrogen stripCarrying out first-stage reduction under the condition to obtain molybdenum-tungsten low-valence oxides; the first-stage reduction is carried out under the condition of temperature gradient, and the specific process is as follows: firstly, preserving heat at the temperature of 400-450 ℃, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.6m3/h；
Step five, second-stage reduction: putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat until the thickness is 1.0cm, and performing second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder; the second-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at 850-880 ℃, then preserving heat at a temperature higher than 880 ℃ and not higher than 920 ℃, preserving heat at a temperature higher than 920 ℃ and not higher than 950 ℃, and finally preserving heat at a temperature higher than 880 ℃ and not higher than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.8m3/h。
By calculation, the theoretical value of the mass content of tungsten in the molybdenum-tungsten alloy powder prepared in the embodiment is 35.59%.
Example 7
The embodiment comprises the following steps:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: 900.26g of deionized water and 900.13g of ammonia water are mixed uniformly to obtain diluted ammonia water, then 900.81g of molybdenum trioxide and 180.16g of tungstic acid are added into the diluted ammonia water under the conditions that the stirring speed is 360r/min and the temperature is 68 ℃, the mixture is stirred and dissolved for 1.5 hours, and the supernatant obtained after solid-liquid separation is the mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor; in the spray drying process, the temperature of an air inlet of the spray drying tower is 190 ℃, the temperature of an air outlet is 123 ℃, and the rotating speed of an atomizer of the spray drying tower is 1.8 multiplied by 104r/min；
Step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a stainless steel material boat until the thickness is 1.0cm, then putting the stainless steel material boat into the air, and roasting and decomposing the molybdenum-tungsten composite oxide precursor under the condition of temperature gradient to obtain a molybdenum-tungsten composite oxide; the roasting decomposition process under the temperature gradient condition comprises the following steps: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 4.1m3/h；
Step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat until the thickness is 0.9cm, and carrying out first-stage reduction under the condition of hydrogen to obtain molybdenum-tungsten low-valence oxide; the first-stage reduction is carried out under the condition of temperature gradient, and the specific process is as follows: firstly, preserving heat at the temperature of 400-450 ℃, then preserving heat at the temperature of more than 450 ℃ and not more than 480 ℃, and preserving heat at the temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.6m3/h；
Step five, second-stage reduction: putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat until the thickness is 1.0cm, and performing second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder; the second-stage reduction is carried out under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at 850-880 ℃, then preserving heat at a temperature higher than 880 ℃ and not higher than 920 ℃, preserving heat at a temperature higher than 920 ℃ and not higher than 950 ℃, and finally preserving heat at a temperature higher than 880 ℃ and not higher than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.9m3/h。
By calculation, the theoretical value of the tungsten mass content in the molybdenum-tungsten alloy powder prepared in the embodiment is 18.11%.
And (3) uniformity analysis of the molybdenum-tungsten alloy powder: (1) according to the theoretical value of the tungsten mass content in the molybdenum-tungsten alloy powder prepared in the embodiments 1 to 7, the molybdenum-tungsten alloy powder reference substances 1 to 7 corresponding to the same tungsten mass content are prepared by a common mechanical mixing method in the prior art, and the specific preparation process comprises the following steps: putting molybdenum powder sieved by a 200-mesh sieve and tungsten powder sieved by a 200-mesh sieve into a three-dimensional mechanical mixing bin, and continuously mixing for 72 hours at a rotation frequency of 30Hz to obtain molybdenum-tungsten alloy powder reference substances 1-7; the powder compositions of molybdenum-tungsten alloy powder reference products No. 1-7 are shown in the following table 1; (2) samples are randomly selected from different parts of the molybdenum-tungsten alloy powder prepared in the embodiments 1 to 7, and the samples are correspondingly divided into a1 group, a2 group, A3 group, a4 group, a5 group, a6 group and a7 group, and each group comprises 7 samples; respectively randomly selecting samples at different parts of the molybdenum-tungsten alloy powder reference substances 1-7 by the same method, and correspondingly setting the samples into a group B1, a group B2, a group B3, a group B4, a group B5, a group B6 and a group B7, wherein each group comprises 7 samples; (3) the mass content of tungsten in each sample of each group in (2) above was measured, the variance S of the mass content of tungsten corresponding to each group was calculated, and the uniformity in the molybdenum-tungsten alloy powder prepared in examples 1 to 7 and the molybdenum-tungsten alloy powder control 1 to 7 was analyzed, and the results are shown in table 2 below.
TABLE 1 composition of Mo-W alloy powder reference 1-7
Table 2 results of uniformity analysis of the molybdenum-tungsten alloy powders prepared in examples 1 to 7 and molybdenum-tungsten alloy powder control samples 1 to 7
As can be seen from table 2, the variances of the groups a1, a2, A3, a4, A5, A6 and a7 in examples 1 to 7 of the present invention are much smaller than the variances of the groups B1, B2, B3, B4, B5, B6 and B7 in the corresponding molybdenum-tungsten alloy powder control 1 to 7, i.e., the variances of the groups a1, a2, A3, a4, A5, A6 and a7 are smaller than the variances of the groups B1, B2, B3, B4, B5, B6 and B7, which indicates that the tungsten content in the groups a1, a2, A3 of the present invention has better uniformity than that in the molybdenum powder prepared by the existing mechanical mixing technology.
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 (8)
1. The preparation method of the molybdenum-tungsten alloy powder is characterized by comprising the following steps of:
step one, preparing a mixed solution of ammonium molybdate and ammonium tungstate: uniformly mixing deionized water and ammonia water to obtain diluted ammonia water, adding molybdenum trioxide and tungstic acid into the diluted ammonia water, stirring and dissolving, and performing solid-liquid separation to obtain a supernatant which is a mixed solution of ammonium molybdate and ammonium tungstate;
step two, preparing a molybdenum-tungsten composite oxide precursor: spray drying the mixed solution of ammonium molybdate and ammonium tungstate obtained in the step one by adopting a spray drying tower to obtain a molybdenum-tungsten composite oxide precursor;
step three, preparing molybdenum-tungsten composite oxide: putting the molybdenum-tungsten composite oxide precursor obtained in the step two into a material boat, then putting the material boat into air, and roasting and decomposing the material under the temperature gradient condition to obtain a molybdenum-tungsten composite oxide;
step four, first-stage reduction: putting the molybdenum-tungsten composite oxide obtained in the third step into a molybdenum boat, and carrying out first-stage reduction under the condition of hydrogen to obtain molybdenum-tungsten low-valence oxide;
step five, second-stage reduction: and (4) putting the molybdenum-tungsten low-valence oxide obtained in the fourth step into a molybdenum boat, and carrying out second-stage reduction under the hydrogen condition to obtain molybdenum-tungsten alloy powder.
2. The preparation method of the molybdenum-tungsten alloy powder according to claim 1, wherein the mass ratio of the tungstic acid to the molybdenum trioxide in the step one is 1 (1-4).
3. The method for preparing the molybdenum-tungsten alloy powder according to claim 1, wherein the mass ratio of the ammonia water to the deionized water in the first step is 1 (1-2), and the mass ratio of the molybdenum trioxide to the deionized water is 1 (1-3); the temperature of stirring and dissolving is 55-75 ℃, the speed is 280-500 r/min, and the time is 1-1.5 h.
4. The method for preparing molybdenum-tungsten alloy powder according to claim 1, wherein in the spray drying process in the second step, the temperature of an air inlet of the spray drying tower is 205-255 ℃, the temperature of an air outlet is 110-155 ℃, and the rotation speed of an atomizer of the spray drying tower is 0.8 x 104r/min～2.0×104r/min。
5. The method of claim 1, wherein the boat in step three is a stainless steel boat.
6. The method for preparing molybdenum-tungsten alloy powder according to claim 1, wherein the thickness of the molybdenum-tungsten composite oxide precursor put into the stainless steel boat in step three is 0.8cm to 1.2cm, and the process of roasting decomposition under the temperature gradient condition is as follows: preserving heat at 380-420 ℃, then preserving heat at a temperature higher than 420 ℃ and not higher than 480 ℃, and preserving heat at a temperature higher than 460 ℃ and not higher than 480 ℃; the boat pushing speed in the roasting decomposition process is 2 boats/30 min, and the air flow is 3.5m3/h～5.6m3/h。
7. The method for preparing molybdenum-tungsten alloy powder according to claim 1, wherein the thickness of the molybdenum-tungsten composite oxide put into the molybdenum boat in the fourth step is 0.5cm to 1.1cm, and the first-stage reduction is performed under the temperature gradient condition, and the specific process is as follows: firstly preserving heat at 400-450 ℃, then preserving heat at a temperature higher than 450 ℃ and not higher than 480 ℃, and then sending toPreserving heat at a temperature of more than 480 ℃ and not more than 550 ℃; the boat pushing speed in the first stage reduction process is 2 boats/40 min, and the hydrogen flow is 0.5m3/h～0.7m3/h。
8. The method for preparing molybdenum-tungsten alloy powder according to claim 1, wherein the thickness of the molybdenum-tungsten suboxide put into the molybdenum boat in the fifth step is 0.5cm to 1.1cm, and the second-stage reduction is performed under the temperature gradient condition, and the specific process is as follows: firstly, preserving heat at 850-880 ℃, then preserving heat at a temperature higher than 880 ℃ and not higher than 920 ℃, preserving heat at a temperature higher than 920 ℃ and not higher than 950 ℃, and finally preserving heat at a temperature higher than 880 ℃ and not higher than 950 ℃; the boat pushing speed in the two-stage reduction process is 1 boat/40 min, and the hydrogen flow is 0.7m3/h～0.9m3/h。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911036941.XA CN110695367A (en) | 2019-10-29 | 2019-10-29 | Preparation method of molybdenum-tungsten alloy powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911036941.XA CN110695367A (en) | 2019-10-29 | 2019-10-29 | Preparation method of molybdenum-tungsten alloy powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110695367A true CN110695367A (en) | 2020-01-17 |
Family
ID=69202636
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911036941.XA Pending CN110695367A (en) | 2019-10-29 | 2019-10-29 | Preparation method of molybdenum-tungsten alloy powder |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110695367A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112209446A (en) * | 2020-09-04 | 2021-01-12 | 崇义章源钨业股份有限公司 | Method for recycling Cr-containing tungsten carbide waste and application thereof |
| CN112222420A (en) * | 2020-12-07 | 2021-01-15 | 西安稀有金属材料研究院有限公司 | Nano tungsten powder doped with metal oxide nano particles and preparation method thereof |
| CN115229180A (en) * | 2022-09-23 | 2022-10-25 | 西安稀有金属材料研究院有限公司 | Preparation method of molybdenum-tungsten nano composite powder with high dispersion and high porosity |
| CN115446323A (en) * | 2022-09-22 | 2022-12-09 | 西北有色金属研究院 | Method for preparing tungsten-molybdenum powder by using waste target scrap powder of tungsten and molybdenum |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56166311A (en) * | 1980-05-26 | 1981-12-21 | Sumitomo Electric Ind Ltd | Manufacture of alloy powder containing molybdenum and tungsten |
| US20020197500A1 (en) * | 2001-05-18 | 2002-12-26 | Ulf Holmqvist | Metal powder |
| CN1393310A (en) * | 2001-06-22 | 2003-01-29 | 中国科学院金属研究所 | Process for preparing nano-class composite W-Cu powder |
| JP2007092089A (en) * | 2005-09-27 | 2007-04-12 | Japan New Metals Co Ltd | Method for producing high-purity molybdenum-tungsten alloy powder used for raw powder for sputtering target |
| CN101851007A (en) * | 2010-05-18 | 2010-10-06 | 华东理工大学 | Tungsten-molybdenum-based superfine composite oxide solid solution and preparation method thereof |
| CN104475759A (en) * | 2015-01-04 | 2015-04-01 | 湖南科技大学 | Preparation method for high-dispersion superfine nanometer Mo-Cu compound powder |
| CN106166613A (en) * | 2016-08-18 | 2016-11-30 | 贵研铂业股份有限公司 | A kind of micron-size spherical W Mo alloy powder and preparation method thereof |
-
2019
- 2019-10-29 CN CN201911036941.XA patent/CN110695367A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56166311A (en) * | 1980-05-26 | 1981-12-21 | Sumitomo Electric Ind Ltd | Manufacture of alloy powder containing molybdenum and tungsten |
| US20020197500A1 (en) * | 2001-05-18 | 2002-12-26 | Ulf Holmqvist | Metal powder |
| CN1393310A (en) * | 2001-06-22 | 2003-01-29 | 中国科学院金属研究所 | Process for preparing nano-class composite W-Cu powder |
| JP2007092089A (en) * | 2005-09-27 | 2007-04-12 | Japan New Metals Co Ltd | Method for producing high-purity molybdenum-tungsten alloy powder used for raw powder for sputtering target |
| CN101851007A (en) * | 2010-05-18 | 2010-10-06 | 华东理工大学 | Tungsten-molybdenum-based superfine composite oxide solid solution and preparation method thereof |
| CN104475759A (en) * | 2015-01-04 | 2015-04-01 | 湖南科技大学 | Preparation method for high-dispersion superfine nanometer Mo-Cu compound powder |
| CN106166613A (en) * | 2016-08-18 | 2016-11-30 | 贵研铂业股份有限公司 | A kind of micron-size spherical W Mo alloy powder and preparation method thereof |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112209446A (en) * | 2020-09-04 | 2021-01-12 | 崇义章源钨业股份有限公司 | Method for recycling Cr-containing tungsten carbide waste and application thereof |
| CN112222420A (en) * | 2020-12-07 | 2021-01-15 | 西安稀有金属材料研究院有限公司 | Nano tungsten powder doped with metal oxide nano particles and preparation method thereof |
| CN112222420B (en) * | 2020-12-07 | 2021-03-16 | 西安稀有金属材料研究院有限公司 | Nano tungsten powder doped with metal oxide nano particles and preparation method thereof |
| CN115446323A (en) * | 2022-09-22 | 2022-12-09 | 西北有色金属研究院 | Method for preparing tungsten-molybdenum powder by using waste target scrap powder of tungsten and molybdenum |
| CN115446323B (en) * | 2022-09-22 | 2024-03-22 | 西北有色金属研究院 | Method for preparing tungsten-molybdenum powder by utilizing waste target scraps of tungsten and molybdenum |
| CN115229180A (en) * | 2022-09-23 | 2022-10-25 | 西安稀有金属材料研究院有限公司 | Preparation method of molybdenum-tungsten nano composite powder with high dispersion and high porosity |
| CN115229180B (en) * | 2022-09-23 | 2022-12-06 | 西安稀有金属材料研究院有限公司 | Preparation method of molybdenum-tungsten nano composite powder with high dispersion and high porosity |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110695367A (en) | Preparation method of molybdenum-tungsten alloy powder | |
| CN102161101B (en) | A method of preparing high purity tungsten material used for very large scale integrated circuits | |
| CN108580917B (en) | Method for preparing tungsten dispersion strengthening copper superfine powder by low-temperature combustion synthesis | |
| US20210146438A1 (en) | Metal material and in-situ exsolution modification method for a surface thereof | |
| CN110627122A (en) | Preparation of VO by solid phase method2Method for phase change materials | |
| CN105551859A (en) | Preparation method of flake silver graphite electrical contact material | |
| CN108911707A (en) | The preparation method of high-density ITO targe material | |
| CN115710124B (en) | Lithium niobate ceramic sputtering target material and preparation method and application thereof | |
| CN111186859B (en) | Superfine V2O5Powder, method for the production thereof and use thereof | |
| JP4060187B2 (en) | Method for producing ITO powder in which tin is dissolved in indium oxide and method for producing ITO target | |
| CN107792891B (en) | Preparation method of nickel cobalt lithium manganate powder | |
| JP5168070B2 (en) | Nickel oxide powder and method for producing the same | |
| CN102730735A (en) | Purification method for strontium carbonate | |
| CN110227825A (en) | A kind of low energy ball milling prepares graphene/copper/cuprous oxide composite granule method | |
| CN113579237A (en) | Preparation method for reducing apparent density of copper-tin alloy powder | |
| CN102864365A (en) | Composite silver stannic oxide electric contact material and preparation method thereof | |
| CN104889416A (en) | Preparation method of silver tin dioxide intermediate composite powder | |
| Wen et al. | Comparison of the interface reaction behaviors of CaO-V2O5 and MnO2-V2O5 solid-state systems based on the diffusion couple method | |
| CN115007163B (en) | Preparation method of supported copper-bismuth catalyst and supported copper-bismuth catalyst | |
| CN110734292B (en) | Method for uniformly mixing CuO and ceramic powder | |
| JP4522535B2 (en) | ITO target manufacturing method | |
| CN101353264B (en) | Method for improving ceramic metallized layer microstructure | |
| CN112357964A (en) | Preparation method of battery-grade trimanganese tetroxide | |
| CN115194173B (en) | New preparation method of nano zirconia dispersion strengthening platinum | |
| CN104498763B (en) | A kind of processing method of siller tin oxide oxide electrical contact material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200117 |