CN117867352A - High volume ratio carbide particle reinforced tungsten metal composite material and preparation method thereof - Google Patents
High volume ratio carbide particle reinforced tungsten metal composite material and preparation method thereof Download PDFInfo
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- 239000002245 particle Substances 0.000 title claims abstract description 79
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 title claims abstract description 60
- 229910052721 tungsten Inorganic materials 0.000 title claims abstract description 40
- 239000010937 tungsten Substances 0.000 title claims abstract description 40
- 239000002905 metal composite material Substances 0.000 title claims abstract description 28
- 238000002360 preparation method Methods 0.000 title abstract description 26
- 239000000919 ceramic Substances 0.000 claims abstract description 26
- 238000001513 hot isostatic pressing Methods 0.000 claims description 67
- 229910001080 W alloy Inorganic materials 0.000 claims description 61
- 239000000843 powder Substances 0.000 claims description 58
- 238000000498 ball milling Methods 0.000 claims description 45
- 238000005245 sintering Methods 0.000 claims description 39
- 238000000034 method Methods 0.000 claims description 36
- 239000000463 material Substances 0.000 claims description 31
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 20
- 229910045601 alloy Inorganic materials 0.000 claims description 20
- 239000000956 alloy Substances 0.000 claims description 20
- 230000009467 reduction Effects 0.000 claims description 19
- 238000000713 high-energy ball milling Methods 0.000 claims description 17
- 238000002156 mixing Methods 0.000 claims description 17
- 238000011049 filling Methods 0.000 claims description 16
- 229910052715 tantalum Inorganic materials 0.000 claims description 16
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims description 16
- 238000007493 shaping process Methods 0.000 claims description 15
- 238000003466 welding Methods 0.000 claims description 15
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 13
- 229910052739 hydrogen Inorganic materials 0.000 claims description 13
- 239000001257 hydrogen Substances 0.000 claims description 13
- 238000011068 loading method Methods 0.000 claims description 13
- 230000008569 process Effects 0.000 claims description 13
- 238000009694 cold isostatic pressing Methods 0.000 claims description 10
- 238000000227 grinding Methods 0.000 claims description 10
- 229910026551 ZrC Inorganic materials 0.000 claims description 9
- OTCHGXYCWNXDOA-UHFFFAOYSA-N [C].[Zr] Chemical compound [C].[Zr] OTCHGXYCWNXDOA-UHFFFAOYSA-N 0.000 claims description 9
- 238000010894 electron beam technology Methods 0.000 claims description 9
- 230000003746 surface roughness Effects 0.000 claims description 9
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 claims description 9
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 6
- 239000011812 mixed powder Substances 0.000 claims description 6
- WHJFNYXPKGDKBB-UHFFFAOYSA-N hafnium;methane Chemical compound C.[Hf] WHJFNYXPKGDKBB-UHFFFAOYSA-N 0.000 claims description 5
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 4
- 229910052719 titanium Inorganic materials 0.000 claims description 4
- 239000010936 titanium Substances 0.000 claims description 4
- 239000003795 chemical substances by application Substances 0.000 claims description 3
- 238000010304 firing Methods 0.000 claims description 2
- 238000009864 tensile test Methods 0.000 description 24
- 230000000052 comparative effect Effects 0.000 description 22
- 239000007769 metal material Substances 0.000 description 13
- 239000002131 composite material Substances 0.000 description 11
- 239000002270 dispersing agent Substances 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 239000012535 impurity Substances 0.000 description 7
- 238000012545 processing Methods 0.000 description 7
- 239000013078 crystal Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 238000001272 pressureless sintering Methods 0.000 description 4
- 230000003014 reinforcing effect Effects 0.000 description 4
- 238000005728 strengthening Methods 0.000 description 4
- 238000005336 cracking Methods 0.000 description 3
- 230000007123 defense Effects 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
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- 238000012986 modification Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 2
- 238000002679 ablation Methods 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
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- 150000001247 metal acetylides Chemical class 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 229910001404 rare earth metal oxide Inorganic materials 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 239000003870 refractory metal Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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Abstract
The invention provides a high volume ratio carbide particle reinforced tungsten metal composite material and a preparation method thereof, wherein the metal composite material consists of 5-70% of carbide ceramic particles and 30-95% of tungsten by volume percent. The high volume ratio carbide particle reinforced tungsten metal composite material has fine and uniform grain structure, the density of the grain structure reaches more than 98 percent, the hardness is not lower than 500HV30, the high-temperature strength is high, and the high-temperature strength at 2000 ℃ can reach 200MPa at the highest.
Description
Technical Field
The invention relates to the technical field of powder metallurgy, in particular to a carbide particle reinforced tungsten metal composite material with high volume ratio and a preparation method thereof.
Background
The metal tungsten has the advantages of high melting point, high-temperature mechanical property, low thermal expansion coefficient and the like, and is widely applied to the fields of aerospace, national defense industry and nuclear industry. However, tungsten has higher density and poorer high-temperature oxidation resistance, and limits the application of the tungsten under the high-temperature service condition.
In order to improve the mechanical properties of tungsten so as to adapt to the high-temperature extreme environment in the advanced technological fields such as aerospace, in the prior art, a trace amount of second phase particles are usually added into tungsten metal, and the high-temperature and ablation resistance of tungsten is improved through deformation strengthening, for example, la is added 2 O 3 The rare earth oxide particles such as (less than 1%) or the carbide particles such as TiC, zrC, hfC (less than 1%) are basically free from the prior art of adding the second phase particles in a high proportion, and the preparation method has the advantages of high preparation difficulty, large brittleness of the material, easiness in cracking during deformation processing, low yield and limited high-temperature strength and hardness improvement. In addition, the density of the composite material is higher due to the lower content of the second phase particles added in the prior art, and the high-temperature strength is low, so that the application of a special extreme service environment cannot be met. Therefore, it is important to develop a tungsten composite material containing a high proportion of reinforcing phase and a preparation method thereof.
In view of this, the present invention has been made.
Disclosure of Invention
The invention aims to provide a carbide particle reinforced tungsten metal composite material with high volume ratio and a preparation method thereof, wherein the grain structure of the composite material is fine and uniform, the density reaches more than 98%, the hardness is not lower than 500HV30, the high-temperature strength is high, and the highest high-temperature strength at 2000 ℃ can reach 200MPa.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the invention provides a high volume ratio carbide particle reinforced tungsten metal composite material, which consists of 5-70% of carbide ceramic particles and 30-95% of tungsten by volume percent.
Further, the carbide ceramic particles include at least one of titanium carbide ceramic particles, zirconium carbide ceramic particles, hafnium carbide ceramic particles.
In addition, the invention also provides a preparation method of the high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Mixing powder: the tungsten powder and the carbide powder are respectively weighed according to the volume percentage of claim 1 or 2 and then mixed, and the mixed powder is subjected to wet ball milling treatment to obtain tungsten alloy powder;
(2) Profiling: filling tungsten alloy powder into a die, and performing cold isostatic pressing to obtain a pressed compact;
(3) Presintering reduction: presintering and reducing the pressed compact obtained in the step (2) in a hydrogen atmosphere sintering furnace to obtain a presintered compact;
(4) Shaping: shaping the pre-sintered blank obtained in the step (3) to a required shape and size;
(5) Hot isostatic pressing: and loading the shaped pre-sintered blank into a sheath, welding a sheath opening, and performing hot isostatic pressing treatment.
Further, the Fisher particle size of the tungsten powder is 1.0-3.0 mu m;
and/or the purity of the tungsten powder is more than or equal to 99.97%;
and/or the particle size of the carbide powder is 20-50 nm.
Further, the ball-to-material ratio in the wet ball milling process in the step (1) is 10-25:1;
and/or the rotation speed of ball milling is 400 rpm-800 rpm;
and/or ball milling time is 20-45h;
and/or the control agent used in the wet ball milling process is ethanol or acetone;
and/or the wet ball milling process comprises the steps of placing mixed powder in a ball milling tank and performing high-energy ball milling under inert atmosphere; preferably, the ball milling tank is a hard alloy ball milling tank, and the grinding balls are hard alloy balls.
Further, the cold isostatic pressing pressure in the step (2) is 150-250MPa;
and/or cold isostatic pressing for 10-20min.
Further, the presintering reduction temperature in the step (3) is 1300-1500 ℃;
and/or sintering time is 4-8h.
Further, the shaping process in the step (4) requires a surface roughness of not more than Ra6.3.
Further, the hot isostatic pressing temperature in the step (5) is 1500-2000 ℃;
and/or the hot isostatic pressure is 150-200MPa;
and/or the hot isostatic pressing treatment time is 4-8h.
Further, the sheath material for hot isostatic pressing in the step (5) is titanium or tantalum;
and/or, the clearance between the pre-sintered blank and the sheath is less than 0.2mm;
and/or using electron beam welding machine to reach 4×10 vacuum degree -2 And welding the sheath mouth after Pa.
Compared with the prior art, the technical scheme of the invention has at least the following technical effects:
(1) According to the invention, the tungsten alloy is prepared by combining wet ball milling of mixed raw materials, cold isostatic pressing, presintering reduction and hot isostatic pressing, the pressureless sintering temperature of the tungsten alloy is reduced by 300-800 ℃ compared with that of the conventional tungsten alloy, and the growth of crystal grains can be inhibited;
(2) According to the invention, the carbide ceramic second phase particles with high volume fraction are added into the tungsten matrix, and the dislocation and the crystal boundary are pricked through the second phase particles for strengthening, so that the movement of the crystal boundary is blocked, the high-temperature performance of the tungsten alloy is improved, and meanwhile, the added ceramic phase has low density, so that the weight of the tungsten alloy can be obviously reduced.
(3) The tungsten alloy prepared by the method has a simple process route, low yield caused by large brittleness of materials can be reduced by combining wet ball milling mixed raw materials, cold isostatic pressing, presintering reduction and hot isostatic pressing, the tungsten carbide ceramic is high in density and difficult to crack during deformation processing when being added in a large proportion, cracks caused by heat deformation processing of refractory metals are avoided, and the prepared material has fine and uniform grain structure, high-temperature strength at 2000 ℃ and highest high-temperature strength reaching 200MPa.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention. Wherein:
fig. 1 is a photograph of a metallographic structure of a high volume ratio carbide particle reinforced tungsten metal composite material prepared in example 1.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions in the embodiments of the present invention will be clearly and completely described in the following in conjunction with the embodiments of the present invention. It will be apparent to those skilled in the art that the examples are merely to aid in understanding the invention and are not to be construed as a specific limitation thereof. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. The process parameters for the specific conditions not noted in the examples below are generally as usual.
The endpoints of the ranges and any values disclosed in the present invention are not limited to the precise range or value, and the range or value should be understood to include values close to the range or value. For numerical ranges, one or more new numerical ranges may be obtained in combination with each other between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point values, and are to be considered as specifically disclosed in the present invention.
According to a first aspect of the present invention there is provided a high volume ratio carbide particle reinforced tungsten metal composite, consisting of tungsten and carbide ceramic particles, the carbide ceramic particles being in the range of 5 to 70% (including 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65% and 70% and any range of values between two points) and the tungsten being in the range of 30 to 95% (including 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% and 95% and any range of values between two points) by volume.
The composite material provided by the invention is mainly used in the fields of aerospace, national defense industry and nuclear industry, the metal composite material is generally composed of a metal phase and a ceramic reinforcing phase, oxides and carbides belong to conventional reinforcing phases, and the carbide rather than the oxide is selected as the ceramic second phase of the composite material, because the melting point of the oxide is lower than that of the carbide, oxide particles are easy to grow up at high temperature, and the reinforcing effect of the oxide is lower than that of the carbide. In addition, the content of carbide needs to be controlled within the scope of the invention, if the content of carbide is too low, the strengthening effect is not obvious, and if the content of carbide is too high, the brittleness of the prepared material is obviously increased, and the preparation difficulty is higher.
As a preferred embodiment of the present invention, the carbide ceramic particles include at least one of titanium carbide (TiC) ceramic particles, zirconium carbide (ZrC) ceramic particles, hafnium carbide (HfC) ceramic particles.
As a preferred embodiment of the invention, the density of the high volume ratio carbide particle reinforced tungsten metal composite material is more than 98 percent (such as 98.2 percent, 98.5 percent, 99 percent, 99.5 percent and the numerical range between any two points), the hardness is not lower than 500HV30 (such as 510HV30, 550HV30, 570HV30, 600HV30 and the numerical range between any two points), and the high temperature strength at 2000 ℃ can reach 200MPa (such as 110MPa, 130MPa, 140MPa, 150MPa, 160MPa, 170MPa, 180MPa, 200MPa and the numerical range between any two points).
According to a second aspect of the present invention, there is also provided a method for preparing the above-mentioned high volume ratio carbide particle reinforced tungsten metal composite material, comprising the steps of:
(1) Mixing powder: respectively weighing tungsten powder and carbide powder according to the volume percentage, mixing, and performing wet ball milling on the mixed powder to obtain tungsten alloy powder;
(2) Profiling: filling tungsten alloy powder into a die, and performing cold isostatic pressing to obtain a pressed compact;
(3) Presintering reduction: presintering and reducing the pressed compact obtained in the step (2) in a hydrogen atmosphere sintering furnace to obtain a presintered compact;
(4) Shaping: shaping the pre-sintered blank obtained in the step (3) to a required shape and size;
(5) Hot isostatic pressing: and loading the shaped pre-sintered blank into a sheath, welding a sheath opening, and performing hot isostatic pressing treatment.
The method can prepare a blank with high density, and the strength and the hardness are also obviously improved, while when the tungsten metal composite material is prepared by adopting common normal-pressure sintering and deformation processing, the sintering density is low, the deformation processing can cause cracking, and the strength and the hardness are not improved. The invention prepares the high-density blank through pressure sintering to improve the performance, solves the problem that the prior ordinary normal pressure sintering process cannot prepare the large-size high-performance blank, but because the second phase particles are added in a high proportion, the brittleness of the material can exist, so that the added carbide is limited in a certain proportion range, and meanwhile, the invention also selects the presintering reduction process to effectively reduce the impurity element content of the blank, thereby improving the brittleness of the material.
In the technical scheme, the wet ball milling is adopted in the step (1), and compared with the dry ball milling, the powder uniformity of the wet ball milling is better; in the step (5), a hot isostatic pressing treatment mode is adopted, compared with SPS discharge plasma sintering, the hot isostatic pressing can prepare large-size products and the pressure is uniform, compared with the conventional pressureless sintering tungsten products, the sintering temperature of the invention is greatly reduced, and the abnormal growth of crystal grains is reduced.
As a preferred embodiment of the present invention, the Fischer particle size of the tungsten powder is 1.0 to 3.0 μm (including 1.0 μm, 1.5 μm, 2.0 μm, 2.5 μm and 3.0 μm and numerical ranges between any two points); the density of the finally obtained composite material is higher by selecting tungsten powder with the granularity.
Preferably, the purity of the tungsten powder is more than or equal to 99.97%;
preferably, the carbide powder has a particle size of 20 to 50nm (including 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, and 50nm and numerical ranges between any two points); the particle size of the carbide powder is preferably controlled within the scope of the present invention, and if the particle size is too small, the particles are liable to agglomerate during the preparation, and if the particle size is too large, the strengthening effect as a ceramic phase is poor.
As a preferred embodiment of the present invention, the ball-to-material ratio during the wet ball milling process in the step (1) is 10-25:1 (including 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1, 20:1, 21:1, 22:1, 23:1, 24:1 and 25:1 and numerical ranges between any two points); the ball material ratio in the invention is preferably controlled within the scope of the invention, if the ball material ratio is too low, the powder refinement is not significant; if the ball-to-material ratio is too high, the powder is refined but agglomerated.
Preferably, the rotational speed of the ball mill is 400rpm to 800rpm (including 400rpm, 500rpm, 600rpm, 700rpm and 800rpm and numerical ranges between any two points);
preferably, the ball milling time is 20-45h (including 20h, 25h, 30h, 35h, 40h and 45h and numerical ranges between any two points);
preferably, the control agent used in the wet ball milling process is ethanol or acetone;
preferably, the wet ball milling process comprises placing the mixed powder in a ball milling tank for high-energy ball milling under inert atmosphere; preferably, the ball milling tank is a hard alloy ball milling tank, and the grinding balls are hard alloy balls.
As a preferred embodiment of the present invention, the cold isostatic press forming in step (2) has a pressure of 150-250MPa (including 150MPa, 160MPa, 170MPa, 180MPa, 190MPa, 200MPa, 210MPa, 220MPa, 230MPa, 240MPa and 250MPa and a numerical range between any two points);
preferably, the cold isostatic pressing is performed for a period of time of 10-20min (including 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min, 19min and 20min and numerical ranges between any two points).
As a preferred embodiment of the present invention, the pre-firing reduction temperature in step (3) is 1300-1500 ℃ (including 1300 ℃, 1320 ℃, 1340 ℃, 1360 ℃, 1380 ℃, 1400 ℃, 1420 ℃, 1440 ℃, 1460 ℃, 1480 ℃ and 1500 ℃ and numerical ranges between any two points); the presintering reduction temperature is preferably controlled within the range, and if the presintering reduction temperature is too high, the subsequent hot isostatic pressing density is lower; if the burn-in temperature is too low, the impurity removal effect is poor.
Preferably, the sintering time is 4-8h (including 4h, 5h, 6h, 7h, and 8h and ranges between any two points). The sintering time is too short, and the impurity removal effect is insufficient; the sintering time is too long, so that more energy is consumed and the production cost is high.
As a preferred embodiment of the present invention, the shaping process in step (4) requires a surface roughness of not more than ra6.3.
As a preferred embodiment of the present invention, the hot isostatic pressing temperature in step (5) is 1500-2000 ℃ (including 1500 ℃, 1550 ℃, 1600 ℃, 1650 ℃, 1700 ℃, 1750 ℃, 1800 ℃, 1850 ℃, 1900 ℃, 1950 ℃ and 2000 ℃ and numerical ranges between any two points); compared with the conventional tungsten alloy, the sintering temperature of the hot isostatic pressing treatment is reduced by 300-800 ℃.
Preferably, the hot isostatic pressure is 150-200MPa (including 150MPa, 160MPa, 170MPa, 180MPa, 190MPa and 200MPa and numerical ranges between any two points);
preferably, the hot isostatic pressing treatment time is 4-8h (including 4h, 5h, 6h, 7h and 8h and numerical ranges between any two points).
In the above technical solution, the temperature, pressure and time of the hot isostatic pressing treatment are preferably controlled within the scope of the present invention, and if the temperature, pressure and time exceed the set ranges, the properties of the finally obtained composite material are reduced.
As a preferred embodiment of the present invention, the sheath material for hot isostatic pressing in step (5) is titanium or tantalum; because the metal phase is tungsten-based and the hot isostatic pressing temperature is higher, the special sheath material such as titanium or tantalum is adopted.
Preferably, the gap between the preform and the sheath is less than 0.2mm;
preferably, the electron beam welding machine is adopted to reach 4X 10 in vacuum degree -2 And welding the sheath mouth after Pa.
The present invention will be described in further detail with reference to specific examples and comparative examples.
Example 1
The embodiment provides a preparation method of a high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Powder preparation: mixing titanium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: tiC=80:20, wet mixing, placing the powder in a ball mill, and performing high-energy ball milling under inert atmosphere, wherein the adopted ball milling tank is a hard alloy ball milling tank, the grinding balls are hard alloy balls, and ethanol is used as a dispersing agent. The rotation speed of the high-energy ball milling is 400rpm, the time is 35h, and the ball-material ratio is 12:1, so as to obtain the mixed tungsten alloy powder;
(2) Filling the tungsten alloy powder obtained in the step one into a die, wherein the cold isostatic pressure is 200MPa, and the pressure maintaining time is 10min;
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1400 ℃, and the sintering time is 6 hours;
(4) Shaping the tungsten alloy pre-sintered blank obtained in the step three, wherein the surface roughness is required to be not more than Ra6.3;
(5) Selecting tantalum as a sheath material, and filling the tungsten alloy pre-sintered blank obtained in the step four into a hot isostatic pressing sheath, wherein the gap between the blank and the tantalum sheath is required to be smaller than 0.2mm;
(6) Electron beam welding is carried out on the blank assembled in the fifth step;
(7) Placing the sheath obtained in the step six into a hot isostatic pressing furnace for hot isostatic pressing treatment, wherein the hot isostatic pressing temperature is 1600 ℃, the hot isostatic pressing pressure is 160Mpa, and the hot isostatic pressing time is 5h;
in the embodiment, the high-temperature tensile test is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the density of the tungsten alloy prepared in the embodiment 1 is 98.5%, the hardness is 620HV30, and the tensile strength at 2000 ℃ reaches 120MPa. As can be seen from FIG. 1, the metal composite material prepared in this example has fine and uniform grains, and an average grain size of 3. Mu.m.
Example 2
The embodiment provides a preparation method of a high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Powder preparation: mixing titanium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: tiC=70:30, wet mixing, placing the powder in a ball mill, and performing high-energy ball milling under inert atmosphere, wherein the adopted ball milling tank is a hard alloy ball milling tank, the grinding balls are hard alloy balls, and ethanol is used as a dispersing agent. The rotation speed of the high-energy ball milling is 400rpm, the time is 35h, and the ball-material ratio is 12:1, so as to obtain the mixed tungsten alloy powder;
(2) Filling the tungsten alloy powder obtained in the step one into a die, wherein the cold isostatic pressure is 200MPa, and the pressure maintaining time is 10min;
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1400 ℃, and the sintering time is 6 hours;
(4) Shaping the tungsten alloy pre-sintered blank obtained in the step three, wherein the surface roughness is required to be not more than Ra6.3;
(5) Selecting tantalum as a sheath material, and filling the tungsten alloy pre-sintered blank obtained in the step four into a hot isostatic pressing sheath, wherein the gap between the blank and the tantalum sheath is required to be smaller than 0.2mm;
(6) Electron beam welding is carried out on the blank assembled in the fifth step;
(7) Placing the sheath obtained in the step six into a hot isostatic pressing furnace for hot isostatic pressing treatment, wherein the hot isostatic pressing temperature is 1700 ℃, the hot isostatic pressing pressure is 170Mpa, and the hot isostatic pressing time is 5h;
in the embodiment, the high-temperature tensile test is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the density of the tungsten alloy prepared in the embodiment 2 is 99.0%, the hardness is 695HV30, and the tensile strength at 2000 ℃ reaches 155MPa.
Example 3
The embodiment provides a preparation method of a high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Powder preparation: mixing zirconium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: zrC=50:50, placing the powder in a ball mill, and performing high-energy ball milling under inert atmosphere, wherein the adopted ball milling tank is a hard alloy ball milling tank, the grinding balls are hard alloy balls, and ethanol is used as a dispersing agent. The rotation speed of the high-energy ball milling is 400rpm, the time is 35h, and the ball-material ratio is 12:1, so as to obtain the mixed tungsten alloy powder;
(2) Filling the tungsten alloy powder obtained in the step one into a die, wherein the cold isostatic pressure is 200MPa, and the pressure maintaining time is 10min;
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1400 ℃, and the sintering time is 6 hours;
(4) Shaping the tungsten alloy pre-sintered blank obtained in the step three, wherein the surface roughness is required to be not more than Ra6.3;
(5) Selecting tantalum as a sheath material, and filling the tungsten alloy pre-sintered blank obtained in the step four into a hot isostatic pressing sheath, wherein the gap between the blank and the tantalum sheath is required to be smaller than 0.2mm;
(6) Electron beam welding is carried out on the blank assembled in the fifth step;
(7) Placing the sheath obtained in the step six into a hot isostatic pressing furnace for hot isostatic pressing treatment, wherein the hot isostatic pressing temperature is 1800 ℃, the hot isostatic pressing pressure is 180Mpa, and the hot isostatic pressing time is 5h;
in the embodiment, the high-temperature tensile test is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the density of the tungsten alloy prepared in the embodiment 3 is 99.1%, the hardness is 816HV30, and the tensile strength at 2000 ℃ reaches 180MPa.
Example 4
The embodiment provides a preparation method of a high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Powder preparation: mixing titanium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: tiC=40:60 is wet mixed, the powder is placed in a ball mill to be subjected to high-energy ball milling under inert atmosphere, a ball milling tank is a hard alloy ball milling tank, grinding balls are hard alloy balls, and ethanol is used as a dispersing agent. The rotation speed of the high-energy ball milling is 400rpm, the time is 35h, and the ball-material ratio is 12:1, so as to obtain the mixed tungsten alloy powder;
(2) Filling the tungsten alloy powder obtained in the step one into a die, wherein the cold isostatic pressure is 200MPa, and the pressure maintaining time is 10min;
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1400 ℃, and the sintering time is 6 hours;
(4) Shaping the tungsten alloy pre-sintered blank obtained in the step three, wherein the surface roughness is required to be not more than Ra6.3;
(5) Selecting tantalum as a sheath material, and filling the tungsten alloy pre-sintered blank obtained in the step four into a hot isostatic pressing sheath, wherein the gap between the blank and the tantalum sheath is required to be smaller than 0.2mm;
(6) Electron beam welding is carried out on the blank assembled in the fifth step;
(7) Placing the sheath obtained in the step six into a hot isostatic pressing furnace for hot isostatic pressing treatment, wherein the hot isostatic pressing temperature is 1900 ℃, the hot isostatic pressing pressure is 200Mpa, and the hot isostatic pressing time is 5h;
in the embodiment, the high-temperature tensile test is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the density of the tungsten alloy prepared in the embodiment 4 is 99.3%, the hardness is 840HV30, and the tensile strength at 2000 ℃ reaches 210MPa.
Example 5
The remaining parameter steps were identical to example 4, except that:
(1) Powder preparation: mixing hafnium carbide powder with the average grain diameter of 40nm with tungsten powder blank with the Fisher grain size of 2 mu m and the purity of more than or equal to 99.97 percent according to the volume percentage W: hfc=90:10 wet mixing.
In the embodiment, the high-temperature tensile test is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the tungsten alloy prepared in the embodiment 1 has the hardness of 99.3 percent, the hardness of 545HV30, and the tensile strength of 2000 ℃ reaches 105MPa.
Example 6
The remaining parameter steps were identical to example 4, except that:
(1) Placing the sheath obtained in the step six into a hot isostatic pressing furnace for hot isostatic pressing treatment, wherein the hot isostatic pressing temperature is 1800 ℃, the hot isostatic pressing pressure is 180Mpa, and the hot isostatic pressing time is 5h;
in the embodiment, the high-temperature tensile test is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the density of the tungsten alloy prepared in the embodiment 6 is 98.6%, the hardness is 815HV30, and the tensile strength at 2000 ℃ reaches 172MPa.
Example 7
The remaining parameter steps were identical to example 1, except that:
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1500 ℃, and the sintering time is 4 hours;
in the embodiment, the high-temperature tensile test is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the density of the tungsten alloy prepared in the embodiment 7 is 98%, the hardness is 606HV30, and the tensile strength at 2000 ℃ reaches 112MPa.
Example 8
The embodiment provides a preparation method of a high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Powder preparation: mixing titanium carbide powder with an average particle size of 60nm with tungsten powder blank with a Fisher particle size of 4 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: tiC=40:60 is wet mixed, the powder is placed in a ball mill to be subjected to high-energy ball milling under inert atmosphere, a ball milling tank is a hard alloy ball milling tank, grinding balls are hard alloy balls, and ethanol is used as a dispersing agent. The rotation speed of the high-energy ball milling is 400rpm, the time is 35h, and the ball-material ratio is 12:1, so as to obtain the mixed tungsten alloy powder;
(2) Filling the tungsten alloy powder obtained in the step one into a die, wherein the cold isostatic pressure is 200MPa, and the pressure maintaining time is 10min;
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1400 ℃, and the sintering time is 6 hours;
(4) Shaping the tungsten alloy pre-sintered blank obtained in the step three, wherein the surface roughness is required to be not more than Ra6.3;
(5) Selecting tantalum as a sheath material, and filling the tungsten alloy pre-sintered blank obtained in the step four into a hot isostatic pressing sheath, wherein the gap between the blank and the tantalum sheath is required to be smaller than 0.2mm;
(6) Electron beam welding is carried out on the blank assembled in the fifth step;
(7) Placing the sheath obtained in the step six into a hot isostatic pressing furnace for hot isostatic pressing treatment, wherein the hot isostatic pressing temperature is 2000 ℃, the hot isostatic pressing pressure is 200Mpa, and the hot isostatic pressing time is 5h;
in the embodiment, the high-temperature stretching experiment is carried out according to GB/T4338-2006 high-temperature stretching test method of metal materials, the density of the prepared tungsten alloy is 98.6%, the hardness is 819HV30, and the tensile strength at 2000 ℃ is 190MPa.
Comparative example 1
The comparative example provides a preparation method of a high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Powder preparation: mixing zirconium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: zrC=50:50, placing the powder in a ball mill, and performing high-energy ball milling under inert atmosphere, wherein the adopted ball milling tank is a hard alloy ball milling tank, the grinding balls are hard alloy balls, and ethanol is used as a dispersing agent. The rotation speed of the high-energy ball milling is 400rpm, the time is 35h, and the ball-material ratio is 12:1, so as to obtain the mixed tungsten alloy powder;
(2) Filling the tungsten alloy powder obtained in the step one into a die, wherein the cold isostatic pressure is 200MPa, and the pressure maintaining time is 10min;
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1400 ℃, and the sintering time is 6 hours;
(4) Shaping the tungsten alloy pre-sintered blank obtained in the step three, wherein the surface roughness is required to be not more than Ra6.3;
(5) Selecting tantalum as a sheath material, and filling the tungsten alloy pre-sintered blank obtained in the step four into a hot isostatic pressing sheath, wherein the gap between the blank and the tantalum sheath is required to be smaller than 0.2mm;
(6) Electron beam welding is carried out on the blank assembled in the fifth step;
(7) Placing the sheath obtained in the step six into a hot isostatic pressing furnace for hot isostatic pressing treatment, wherein the hot isostatic pressing temperature is 1400 ℃, the hot isostatic pressing pressure is 180Mpa, and the hot isostatic pressing time is 5h;
the high-temperature tensile test in the comparative example is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, the density of the prepared tungsten alloy is 96.2%, the hardness is 613HV30, and the tensile strength at 2000 ℃ reaches 135MPa.
Comparative example 2
The remaining parameter steps were identical to example 3, except that:
(1) Mixing zirconium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: zrc=20:80.
After the blank is subjected to hot isostatic pressing, the blank is broken and cannot be processed due to the fact that the ceramic content is too high in the process of removing the sheath.
Comparative example 3
The remaining parameter steps were identical to example 3, except that:
(1) Mixing zirconium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: zrc=98:2.
The high-temperature tensile test in the comparative example is carried out according to GB/T4338-2006 high-temperature tensile test method of metal materials, and the density of the prepared tungsten alloy is 99.5%, the hardness is 440HV30, and the tensile strength at 2000 ℃ is 60MPa.
Comparative example 4
The comparative example provides a preparation method of a high volume ratio carbide particle reinforced tungsten metal composite material, which comprises the following steps:
(1) Powder preparation: mixing zirconium carbide powder with an average particle size of 30nm with tungsten powder blank with a Fisher particle size of 1.5 mu m and a purity of more than or equal to 99.97 percent according to the volume percentage W: zrC=50:50, placing the powder in a ball mill, and performing high-energy ball milling under inert atmosphere, wherein the adopted ball milling tank is a hard alloy ball milling tank, the grinding balls are hard alloy balls, and ethanol is used as a dispersing agent. The rotation speed of the high-energy ball milling is 400rpm, the time is 35h, and the ball-material ratio is 12:1, so as to obtain the mixed tungsten alloy powder;
(2) Filling the tungsten alloy powder obtained in the step one into a die, wherein the cold isostatic pressure is 200MPa, and the pressure maintaining time is 10min;
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for pressureless sintering, wherein the sintering temperature is 2300 ℃, and the sintering time is 6 hours;
the high-temperature tensile test in the comparative example is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, and the prepared tungsten alloy has the density of 85 percent, the hardness of 412HV30 and the tensile strength of 50MPa at 2000 ℃.
Comparative example 5
The remaining parameter steps were identical to example 1, except that:
(3) And (3) loading the tungsten alloy pressed compact obtained in the step (II) into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1200 ℃, and the sintering time is 6 hours.
The comparative example has low pre-sintering temperature, poor impurity removing effect, high impurity element content, high brittleness and easy cracking during material processing.
Comparative example 6
The remaining parameter steps were identical to example 1, except that:
(3) Loading the tungsten alloy pressed compact obtained in the second step into a hydrogen atmosphere sintering furnace for presintering reduction, wherein the presintering temperature is 1600 ℃, and the sintering time is 6 hours;
the high-temperature tensile test in the comparative example is carried out according to GB/T4338-2006 high-temperature tensile test method for metallic materials, and the density of the prepared tungsten alloy is 97.6%, the hardness is 593HV30, and the tensile strength at 2000 ℃ is 105MPa.
The high volume ratio carbide particle reinforced tungsten metal composites obtained in examples 1 to 8 and comparative examples 1 to 6 were subjected to a high temperature tensile test according to GB/T4338-2006 Metal Material high temperature tensile test method, and specific test results obtained are shown in Table 1:
TABLE 1
From the above data, it can be seen that the high volume ratio carbide particle reinforced tungsten metal composites obtained in examples 1-8 have significantly higher overall properties than comparative examples 1-6. The hot isostatic pressing treatment temperature in comparative example 1 was lower than the preferred range of the present invention, resulting in a composite material having reduced hardness and tensile strength at 2000 ℃; in comparative example 2, the addition of too high a ceramic phase particle content resulted in fracture of the ingot; the addition of the ceramic phase particles in comparative example 3 is too low, and the hardness and the tensile strength at 2000 ℃ of the prepared composite material are obviously reduced; in comparative example 4, after pressureless sintering is adopted to replace the hot isostatic pressing molding of the invention, the hardness, the tensile strength at 2000 ℃ and the compactness of the prepared composite material are obviously reduced; in comparative example 5, the pre-sintering temperature is low, the impurity removing effect is poor, the impurity element content is high, and the brittleness is high and the material is easy to crack during processing; in comparative example 6, since the pre-sintering temperature was higher than the preferred range of the present invention, the hardness and tensile strength at 2000℃of the obtained composite material were lowered.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The high volume ratio carbide particle reinforced tungsten metal composite material is characterized by comprising 5-70% of tungsten and 30-95% of carbide ceramic particles by volume percent.
2. The high volume ratio carbide particle reinforced tungsten metal composite of claim 1, wherein the carbide ceramic particles comprise at least one of titanium carbide ceramic particles, zirconium carbide ceramic particles, hafnium carbide ceramic particles.
3. A method for preparing the high volume ratio carbide particle reinforced tungsten metal composite material according to claim 1 or 2, comprising the steps of:
(1) Mixing powder: the tungsten powder and the carbide powder are respectively weighed according to the volume percentage of claim 1 or 2 and then mixed, and the mixed powder is subjected to wet ball milling treatment to obtain tungsten alloy powder;
(2) Profiling: filling tungsten alloy powder into a die, and performing cold isostatic pressing to obtain a pressed compact;
(3) Presintering reduction: presintering and reducing the pressed compact obtained in the step (2) in a hydrogen atmosphere sintering furnace to obtain a presintered compact;
(4) Shaping: shaping the pre-sintered blank obtained in the step (3) to a required shape and size;
(5) Hot isostatic pressing: and loading the shaped pre-sintered blank into a sheath, welding a sheath opening, and performing hot isostatic pressing treatment.
4. The method according to claim 3, wherein the tungsten powder has a Fisher size of 1.0 to 3.0 μm;
and/or the purity of the tungsten powder is more than or equal to 99.97%;
and/or the particle size of the carbide powder is 20-50 nm.
5. The method according to claim 3, wherein the ball-to-material ratio in the wet ball milling process in the step (1) is 10-25:1;
and/or the rotation speed of ball milling is 400 rpm-800 rpm;
and/or ball milling time is 20-45h;
and/or the control agent used in the wet ball milling process is ethanol or acetone;
and/or the wet ball milling process comprises the steps of placing mixed powder in a ball milling tank and performing high-energy ball milling under inert atmosphere; preferably, the ball milling tank is a hard alloy ball milling tank, and the grinding balls are hard alloy balls.
6. The method according to claim 3, wherein the cold isostatic pressing pressure in the step (2) is 150-250MPa;
and/or cold isostatic pressing for 10-20min.
7. The method according to claim 3, wherein the pre-firing reduction temperature in the step (3) is 1300-1500 ℃;
and/or sintering time is 4-8h.
8. A method according to claim 3, wherein the shaping in step (4) requires a surface roughness of no more than ra6.3.
9. The method of claim 3, wherein the hot isostatic pressing temperature in step (5) is 1500-2000 ℃;
and/or the hot isostatic pressure is 150-200MPa;
and/or the hot isostatic pressing treatment time is 4-8h.
10. The method according to claim 3, wherein the sheath material for hot isostatic pressing in the step (5) is titanium or tantalum;
and/or, the clearance between the pre-sintered blank and the sheath is less than 0.2mm;
and/or using electron beam welding machine to reach 4×10 vacuum degree -2 And welding the sheath mouth after Pa.
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