Tungsten-silicon alloy material and preparation method and application thereof

Abstract

The invention provides a tungsten-silicon alloy material and a preparation method and application thereof. The preparation method comprises the following steps that (1) tungsten powder and silicon powder are mixed and then subjected to suspension smelting treatment, and alloy liquid is obtained; (2) the alloy liquid is subjected to forming and outer circle grinding treatment, and a tungsten-silicon alloy cast ingot is obtained; and (3) the tungsten-silicon alloy ingot is subjected to ion rotating electrode atomization powder processing, and the tungsten-silicon alloy material is obtained. According to the method, the problems of mixing and homogenization of tungsten and silicon in the melting process can be effectively solved, the oxygen content in the alloy is reduced, the purity of the alloy is improved, the strength of the cast ingot is improved, and the problem that the cast ingot is broken in the atomization powder manufacturing process of the ion rotating electrode is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of powder metallurgy and relates to a tungsten-silicon alloy material and a preparation method and application thereof. Background Art

[0002] Powder metallurgy is an important material preparation technology, which prepares metal materials with certain shapes and properties by mixing, pressing and sintering metal powders. Among them, tungsten silicon alloy is an important high-temperature structural material. Because of its good high-temperature strength, thermal stability and corrosion resistance, it is widely used in semiconductor integrated circuit gate materials, electronic films, aerospace, nuclear energy and military fields.

[0003] Tungsten silicon alloy materials have extremely important applications in the fields of semiconductor integrated circuit gate materials and electronic thin films. With the continuous improvement of target material purity and element uniformity, the stability of the sputtered film is better, and the performance of semiconductor circuits is continuously improved. Traditional tungsten silicon alloy preparation methods often require high temperature and high pressure conditions, high energy consumption, and the prepared alloy structure is uneven and the performance is unstable. At present, the traditional sintering method is commonly used for hot pressing sintering. First, a certain proportion of tungsten powder and silicon powder are mixed as required. After the mixing is completed, the alloy powder is molded and then hot pressed and sintered to obtain the product.

[0004] CN116571757A discloses a high-purity tungsten-silicon composite powder and a preparation method thereof. The preparation method of the embodiment comprises the following steps: mixing high-purity tungsten oxide powder with purified SiHCl 3 The solutions are mixed to obtain a mixture; the mixture is heated and reduced with hydrogen to obtain a high-purity tungsten-silicon composite powder.

[0005] CN117646176A discloses a method for preparing a tungsten-silicon alloy target material, the preparation method comprising: mixing tungsten powder and silicon powder and pressing them together, followed by hot pressing and sintering to obtain a tungsten-silicon alloy target material; wherein the pressing includes a first pressing and a gradient ultrasonic pressing performed in sequence; in the gradient ultrasonic pressing, the pressure and the ultrasonic power are increased synchronously.

[0006] The above scheme requires high temperature and high pressure conditions, high energy consumption, and the prepared alloy has uneven structure and unstable performance. It has defects such as low uniformity of element distribution and difficult purity control. The preparation process is often accompanied by cracking of sintered products, and the yield is low. Summary of the invention

[0007] The object of the present invention is to provide a tungsten-silicon alloy material and a preparation method and application thereof. The method of the present invention can effectively solve the problem of mixing and homogenizing tungsten and silicon during the melting process, reduce the oxygen content in the alloy, improve the purity of the alloy, improve the strength of the ingot, and solve the problem of ingot breakage in the ion rotating electrode atomization powder making process.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a method for preparing a tungsten-silicon alloy material, the preparation method comprising the following steps:

[0010] (1) mixing tungsten powder and silicon powder and performing suspension smelting to obtain alloy liquid;

[0011] (2) forming and cylindrically grinding the alloy liquid to obtain a tungsten-silicon alloy ingot;

[0012] (3) The tungsten silicon alloy ingot is subjected to ion rotating electrode atomization powder making treatment to obtain the tungsten silicon alloy material.

[0013] The present invention uniformly alloys the metal through suspension smelting, thereby obtaining a tungsten-silicon alloy with a uniform structure, improving the performance stability of the alloy, and the suspension smelting can effectively prevent air from entering. Inert gas is filled during the smelting process to reduce the oxygen content in the alloy, and external cylindrical grinding is performed to remove surface oxides and impurities, further improving the purity of the alloy. Then, through ion rotating electrode atomization powder preparation, tiny spherical low-oxygen tungsten-silicon alloy powder can be effectively prepared, the alloying is sufficient, the prepared product has a uniform structure, and meets the needs of practical applications, and the particle size of the spherical powder can be solved by the rotation speed during the powder preparation process.

[0014] Preferably, based on the total mass of the tungsten powder and the silicon powder as 100%, the mass fraction of the silicon powder is 28-30%, for example, 28%, 28.5%, 29%, 29.5% or 30%, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0015] Preferably, the atmosphere of the suspension smelting treatment in step (1) comprises argon and / or nitrogen.

[0016] Preferably, the temperature of the suspension smelting treatment in step (1) is 2400-2600°C, for example, 2400°C, 2450°C, 2500°C, 2550°C or 2600°C, etc., not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0017] The suspension smelting process described in the present invention is a technology that uses an electromagnetic field to make the molten pool present a suspended state during the vacuum smelting process. The electromagnetic force suspension technology is used to suspend the molten alloy melt without contacting the crucible to obtain a high-cleanliness smelting method.

[0018] Preferably, the forming method in step (2) includes ingot drawing and / or casting.

[0019] Preferably, the grinding wheel mesh number used in the cylindrical grinding process in step (2) is 700-900 mesh, for example: 700 mesh, 750 mesh, 800 mesh, 850 mesh or 900 mesh, etc., not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] Preferably, the surface roughness of the material obtained after the cylindrical grinding process in step (2) is Ra≤2.0 μm.

[0021] The present invention can effectively reduce the shrinkage cavity and material stress inside the ingot by forming and cylindrical grinding, so that the ingot can resist the high-strength centrifugal force generated during high-speed rotation. Then, the ingot is subjected to cylindrical grinding to remove surface oxides and impurities, thereby obtaining a regular tungsten silicon alloy ingot with low surface roughness. This method can further improve the purity of the alloy, and also prepare for the next step of ion rotating electrode atomization powder making.

[0022] Preferably, the ingot is cleaned after the cylindrical grinding process in step (2).

[0023] The present invention cleans the ingot after grinding with high cleanliness through ingot cleaning, thereby reducing the pollution to the granulated powder.

[0024] Preferably, the purity of the tungsten-silicon alloy ingot in step (2) is ≥5N.

[0025] Preferably, the rotation speed of the ion rotating electrode atomization powder processing in step (3) is 5000-10000 rpm, for example: 5000 rpm, 6000 rpm, 8000 rpm, 9000 rpm or 10000 rpm, etc., not limited to the listed values, other values ​​not listed within the numerical range are also applicable.

[0026] Preferably, the temperature of the ion rotating electrode atomization powder making process in step (3) is ≥ 2600°C.

[0027] The ion rotating electrode atomization powder making process of the present invention is to arc and melt the end of the high-speed rotating electrode rod through plasma, and use the centrifugal force generated by the high-speed rotation of the electrode rod to throw the molten metal into fine droplets, and the atomized metal droplets are condensed into spherical powder after heat exchange with the atmosphere.

[0028] In a second aspect, the present invention provides a tungsten-silicon alloy material, which is prepared by the method described in the first aspect.

[0029] In a third aspect, the present invention provides an application of the tungsten-silicon alloy material as described in the second aspect, wherein the tungsten-silicon alloy material is used for semiconductor devices and / or aerospace devices.

[0030] The tungsten silicon alloy of the present invention has the characteristics of low resistivity, strong thermal stability and excellent chemical corrosion resistance, and is an important component of semiconductor integrated circuits, mainly used as a gate contact layer, a diffusion barrier layer or an adhesion layer. Due to its excellent performance, the silicon tungsten alloy material can also be used to manufacture the rotor of the gyroscope in aerospace devices, the balance weight of the aircraft and the control rudder, etc.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The method of the present invention can effectively solve the problem of mixing and homogenizing tungsten and silicon during the melting process, reduce the oxygen content in the alloy, improve the purity of the alloy, improve the strength of the ingot, and solve the problems of ingot breakage and ingot shrinkage control in the ion rotating electrode atomization powder making process.

[0033] (2) The particle size of the tungsten silicon alloy material prepared by the method of the present invention can reach within 236 μm, the oxygen content can reach below 144 ppm, the output rate can reach more than 76%, and the purity can reach 5N. During the preparation process, the ingot obtained in step (2) has a complete shape. DETAILED DESCRIPTION

[0034] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0035] Example 1

[0036] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0037] (1) mixing tungsten powder and silicon powder in a mass ratio of 71:29 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2450° C. to obtain an alloy liquid;

[0038] (2) After the alloy liquid is formed into an ingot, an 800-mesh grinding wheel is used for external cylindrical grinding to achieve a surface roughness of Ra=2.0 μm. After cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0039] (3) The tungsten silicon alloy ingot is subjected to an ion rotating electrode atomization powder making process to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making process is 8000 rpm and the temperature is 2650°C.

[0040] Example 2

[0041] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0042] (1) mixing tungsten powder and silicon powder in a mass ratio of 70:30 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2500° C. to obtain an alloy liquid;

[0043] (2) After the alloy liquid is cast and formed, it is subjected to external cylindrical grinding using a 700-mesh grinding wheel to achieve a surface roughness of Ra=2.0 μm, and after cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0044] (3) The tungsten silicon alloy ingot is subjected to an ion rotating electrode atomization powder making process to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making process is 5000 rpm and the temperature is 2800°C.

[0045] Example 3

[0046] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0047] (1) mixing tungsten powder and silicon powder in a mass ratio of 72:28 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2400° C. to obtain an alloy liquid;

[0048] (2) After the alloy liquid is pulled into an ingot, it is subjected to external cylindrical grinding using a 900-mesh grinding wheel to achieve a surface roughness of Ra=2.0 μm. After cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0049] (3) The tungsten silicon alloy ingot is subjected to an ion rotating electrode atomization powder making process to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making process is 10000 rpm and the temperature is 2700°C.

[0050] Example 4

[0051] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0052] (1) mixing tungsten powder and silicon powder in a mass ratio of 73:27 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2450° C. to obtain an alloy liquid;

[0053] (2) After the alloy liquid is formed into an ingot, an 800-mesh grinding wheel is used for external cylindrical grinding to achieve a surface roughness of Ra=2.0 μm. After cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0054] (3) The tungsten silicon alloy ingot is subjected to an ion rotating electrode atomization powder making process to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making process is 8000 rpm and the temperature is 2650°C.

[0055] Example 5

[0056] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0057] (1) mixing tungsten powder and silicon powder in a mass ratio of 69:31 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2450° C. to obtain an alloy liquid;

[0058] (2) After the alloy liquid is formed into an ingot, an 800-mesh grinding wheel is used for external cylindrical grinding to achieve a surface roughness of Ra=2.0 μm. After cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0059] (3) The tungsten silicon alloy ingot is subjected to an ion rotating electrode atomization powder making process to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making process is 8000 rpm and the temperature is 2650°C.

[0060] Example 6

[0061] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0062] (1) mixing tungsten powder and silicon powder in a mass ratio of 71:29 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2450° C. to obtain an alloy liquid;

[0063] (2) After the alloy liquid is formed into an ingot, an 800-mesh grinding wheel is used for external cylindrical grinding to achieve a surface roughness of Ra=2.0 μm. After cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0064] (3) The tungsten silicon alloy ingot is subjected to an ion rotating electrode atomization powder making process to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making process is 3000 rpm and the temperature is 2650°C.

[0065] Example 7

[0066] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0067] (1) mixing tungsten powder and silicon powder in a mass ratio of 71:29 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2450° C. to obtain an alloy liquid;

[0068] (2) After the alloy liquid is formed into an ingot, an 800-mesh grinding wheel is used for external cylindrical grinding to achieve a surface roughness of Ra=2.0 μm. After cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0069] (3) The tungsten silicon alloy ingot is subjected to an ion rotating electrode atomization powder making process to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making process is 15000 rpm and the temperature is 2650°C.

[0070] Example 8

[0071] This embodiment provides a tungsten-silicon alloy material, and the preparation method of the tungsten-silicon alloy material is as follows:

[0072] (1) mixing tungsten powder and silicon powder in a mass ratio of 71:29 by a powder mixer to obtain a mixed material, introducing argon gas into a suspension melting furnace, and performing suspension melting treatment at 2450° C. to obtain an alloy liquid;

[0073] (2) After the alloy liquid is formed into an ingot, an 800-mesh grinding wheel is used for external cylindrical grinding to achieve a surface roughness of Ra=2.0 μm. After cleaning, a tungsten-silicon alloy ingot with a purity of 5N is obtained;

[0074] (3) The tungsten silicon alloy ingot is subjected to ion rotating electrode atomization powder making treatment to obtain the tungsten silicon alloy material, wherein the rotation speed of the ion rotating electrode atomization powder making treatment is 8000 rpm and the temperature is 2500°C.

[0075] Comparative Example 1

[0076] The only difference between this comparative example and Example 1 is that the suspension smelting process is replaced by conventional melting process, and the other conditions and parameters are exactly the same as those in Example 1.

[0077] Comparative Example 2

[0078] The only difference between this comparative example and Example 1 is that the ion rotating electrode atomization powder making process is replaced by planetary ball milling, and the other conditions and parameters are exactly the same as those in Example 1.

[0079] Performance Test:

[0080] The tungsten silicon alloy materials obtained in the embodiment and the comparative example were tested by GDMS, laser particle size analyzer and oxygen content detection equipment. The test results are shown in Table 1:

[0081] Table 1

[0082]

[0083]

[0084] As can be seen from Table 1, from Examples 1-3, the particle size of the tungsten silicon alloy material prepared by the method of the present invention can reach within 73μm, the oxygen content can reach below 105ppm, the output rate can reach more than 97%, and the purity can reach 5N. During the preparation process, the ingot obtained in step (2) has a complete shape.

[0085] By comparing Example 1 with Examples 4-5, it can be seen that in the preparation process of the tungsten-silicon alloy material of the present invention, the ratio of tungsten powder to silicon powder will affect its performance. By controlling the mass of silicon powder to 28-30% of the total mass of silicon powder and tungsten powder, the performance of the tungsten-silicon alloy material obtained is better. If the proportion of silicon powder is too high, the brittleness of the ingot will increase, and the difficulty of suspended smelting ingot pulling will be increased. The ingot pulling is prone to ingot head breakage and shrinkage holes, affecting the output quality.

[0086] By comparing Example 1 with Examples 6-7, it can be seen that the rotation speed of the ion rotating electrode atomization powder making process during the preparation of the tungsten silicon alloy material of the present invention will affect its performance. When the rotation speed of the ion rotating electrode atomization powder making process is controlled at 5000-10000 rpm, the performance of the tungsten silicon alloy material obtained is better. If the rotation speed of the ion rotating electrode atomization powder making process is too high, the ingot will break. If the rotation speed of the ion rotating electrode atomization powder making process is too low, the powder production efficiency will be reduced.

[0087] By comparing Example 1 and Example 8, it can be seen that the temperature of the ion rotating electrode atomization powder making process during the preparation of the tungsten silicon alloy material of the present invention will affect its performance. When the temperature of the ion rotating electrode atomization powder making process is controlled at above 2600°C, the performance of the tungsten silicon alloy material obtained is better. If the temperature of the ion rotating electrode atomization powder making process is too low, the ingot cannot be melted, resulting in difficulty in producing powder.

[0088] From the comparison between Example 1 and Comparative Example 1, it can be seen that the suspension smelting process of the present invention can make the metal uniform and alloyed, and further improve the performance of the alloy. At the same time, the suspension smelting furnace can effectively prevent air from entering, and inert gas is filled in the smelting process, thereby reducing the oxygen content in the alloy and improving the purity of the alloy.

[0089] By comparing Example 1 and Comparative Example 2, it can be seen that the present invention can effectively prepare tiny spherical low-oxygen tungsten-silicon alloy powder through ion rotating electrode atomization powder preparation treatment, the alloying is sufficient, the prepared product has uniform structure, meets the needs of practical applications, and the particle size of the spherical powder can be solved by the rotation speed during the powder preparation process, thereby improving the flexibility and applicability of the product.

[0090] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a tungsten silicon alloy material, characterized in that: The preparation method comprises the following steps: (1) mixing tungsten powder and silicon powder and performing suspension smelting to obtain alloy liquid; (2) forming and cylindrically grinding the alloy liquid to obtain a tungsten silicon alloy ingot; (3) The tungsten silicon alloy ingot is subjected to ion rotating electrode atomization powder making treatment to obtain the tungsten silicon alloy material.

2. The preparation method according to claim 1, characterized in that Taking the total mass of the tungsten powder and the silicon powder as 100%, the mass fraction of the silicon powder is 28-30%.

3. The preparation method according to claim 1 or 2, characterized in that: The atmosphere of the suspension smelting treatment in step (1) comprises argon and / or nitrogen; Preferably, the temperature of the suspension smelting treatment in step (1) is 2400-2600°C.

4. The preparation method according to any one of claims 1 to 3, characterized in that: The forming method in step (2) includes ingot drawing and / or casting.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The grinding wheel used in the cylindrical grinding process in step (2) has a mesh size of 700 to 900; Preferably, the surface roughness of the material obtained after the cylindrical grinding process in step (2) is Ra≤2.0 μm.

6. The preparation method according to any one of claims 1 to 5, characterized in that: After the cylindrical grinding process in step (2), the ingot is cleaned.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The purity of the tungsten-silicon alloy ingot in step (2) is ≥5N.

8. The preparation method according to any one of claims 1 to 7, characterized in that: The rotation speed of the ion rotating electrode atomization powder making process in step (3) is 5000-10000 rpm; Preferably, the temperature of the ion rotating electrode atomization powder making process in step (3) is ≥ 2600°C.

9. A tungsten silicon alloy material, characterized in that: The tungsten silicon alloy material is obtained by the method as described in any one of claims 1-8.

10. An application of the tungsten silicon alloy material as claimed in claim 9, characterized in that: The tungsten-silicon alloy material is used for semiconductor devices and / or aerospace devices.

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