Ceramic phase reinforced refractory high-entropy alloy composite material and preparation method thereof

文档序号:389243 发布日期:2021-12-14 浏览:13次 中文

阅读说明:本技术 陶瓷相增强难熔高熵合金复合材料及其制备方法 (Ceramic phase reinforced refractory high-entropy alloy composite material and preparation method thereof ) 是由 沈宝龙 王冰洁 王倩倩 孙博 郭杨斌 于 2021-08-16 设计创作,主要内容包括:本发明涉及陶瓷相增强难熔高熵合金复合材料及其制备方法,属于材料科学与工程技术领域,本发明通过添加陶瓷相,并使用非自耗真空电弧熔炼炉制备出了一系列陶瓷相增强难熔高熵合金复合材料。本发明的制备方法,工艺简单,便于操作;该合金呈单一BCC结构,微观组织形貌主要为树枝晶,在引入纳米第二相的同时引入间隙原子,使得平均晶粒尺寸相较于基体难熔高熵合金明显减小,室温及高温力学性能明显提高,在800℃下具有优异的高温组织结构稳定性。本发明能显著提高机械工程装备及部件的使役温度,有望取代镍基超级合金在航空航天、交通运输、石油化工、机械电子、汽车制造等领域具有广阔的应用前景。(The invention relates to a ceramic phase reinforced refractory high-entropy alloy composite material and a preparation method thereof, belonging to the technical field of material science and engineering. The preparation method of the invention has simple process and convenient operation; the alloy is of a single BCC structure, the microstructure appearance is mainly dendritic crystals, and interstitial atoms are introduced while a nano second phase is introduced, so that the average grain size is obviously reduced compared with that of a matrix refractory high-entropy alloy, the room temperature and high-temperature mechanical properties are obviously improved, and the alloy has excellent high-temperature structural stability at 800 ℃. The invention can obviously improve the service temperature of mechanical engineering equipment and parts, and is expected to replace nickel-based superalloy, thereby having wide application prospect in the fields of aerospace, transportation, petrochemical industry, mechanical electronics, automobile manufacturing and the like.)

1. The ceramic phase reinforced refractory high-entropy alloy composite material is characterized by comprising 4-6 metal elements and a ceramic phase according to an atomic ratio, wherein the 4-6 metal elements are selected from W, Re, Ta, Mo, Nb, Hf, Zr, Ti, V and Cr; the atomic percentage content of each metal element is a, and the a is more than or equal to 5% and less than or equal to 35%; the ceramic phase has the atomic percentage content of b, and b is more than or equal to 1% and less than or equal to 20%.

2. The ceramic phase reinforced refractory high entropy alloy composite material of claim 1, wherein the ceramic phase is selected from Al2O3、Y2O3、SiC、AlN、TiB2Any one or a combination of several of them.

3. The preparation method of the ceramic phase reinforced refractory high-entropy alloy composite material of claim 1, characterized by comprising the following steps: the method comprises the following steps:

step 1: taking corresponding simple substance pure metal raw materials according to the types of alloy components, carrying out ultrasonic cleaning and blow-drying, and accurately batching according to alloy components;

step 2: sequentially placing the weighed raw materials of the elements into a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, placing the ceramic phase at the bottommost part, and pumping the air pressure of a vacuum chamber of the vacuum arc melting furnace to 5 multiplied by 10-3Pa below;

and step 3: vacuum arc melting, wherein in order to ensure the uniformity of the alloy, the alloy is melted and then melted;

and 4, step 4: and cooling the ceramic phase-reinforced refractory high-entropy alloy composite material to room temperature in a vacuum chamber, taking out the ceramic phase-reinforced refractory high-entropy alloy composite material, and carrying out vacuum suction casting or vacuum casting to obtain the ceramic phase-reinforced refractory high-entropy alloy composite material.

4. The preparation method of the ceramic phase reinforced refractory high-entropy alloy composite material according to claim 3, characterized in that: in the step 3, the smelting time of each alloy ingot is 160-200s after the alloy is melted, and each alloy ingot is smelted 6-8 times.

5. The preparation method of the ceramic phase reinforced refractory high-entropy alloy composite material according to claim 3, characterized in that: in the step 4, vacuum casting is adopted, specifically, the cast ingot is placed in a vacuum suction casting furnace, a casting mold is used, and the vacuum is pumped to 5 multiplied by 10-3And Pa, adopting 350-400A current to melt the ingot and then casting.

6. The preparation method of the ceramic phase reinforced refractory high-entropy alloy composite material according to claim 3, characterized in that: in the step 4, vacuum suction casting is adopted, specifically, the cast ingot is placed in a vacuum suction casting furnace, a suction casting mold is used, and the vacuum is pumped to 5 multiplied by 10-3Pa, the pressure difference is adjusted to 4 atmospheric pressures, and the ingot is melted by adopting 350-400A current and then is rapidly suction cast.

Technical Field

The invention belongs to the technical field of material science and engineering, and particularly relates to a ceramic phase reinforced refractory high-entropy alloy composite material and a preparation method thereof.

Background

The refractory high-entropy alloy is a solid solution with a simple crystal structure formed by taking four or more refractory elements as main elements and an equal atomic ratio or a nearly equal atomic ratio, and is a novel high-entropy alloy system developed based on development of high-temperature structural metals. The first alloy with specific alloy components was published and reported by the us air force laboratory Senkov et al in 2010, and the refractory high-entropy alloy has been greatly developed in the last decade. The refractory high-entropy alloy has great application potential in the field of extreme service environments such as navigation and aerospace, deep space exploration, national defense and military industry, nuclear power energy and the like due to the advantages of simple phase structure, excellent high-temperature softening resistance, good corrosion resistance and the like.

The refractory high-entropy alloy component is a refractory metal element, comprises Mo, Ti, V, Nb, Hf, Ta, Cr, W and Zr, and has two main systems of NbMoTaW and HfNbTaTiZr. The excellent high-temperature mechanical property and structural stability of the NbMoTaW alloy enable the NbMoTaW alloy to be expected to be applied to an extreme high-temperature environment, but the NbMoTaW alloy has the defects of high alloy density, insufficient room-temperature strength, high brittleness, poor oxidation resistance and the like, and the application of the NbMoTaW alloy is severely limited. The HfNbTaTiZr refractory high-entropy alloy has the advantages of low density, high room-temperature toughness, good processability and excellent corrosion resistance, but the high-temperature softening resistance of the HfNbTaTiZr refractory high-entropy alloy is rapidly reduced under high-temperature and ultrahigh-temperature environments, and the service requirement of high-temperature structural components cannot be met.

In order to solve the problems, researchers apply concepts such as metal element alloying, phase structure design and non-metal element doping in the traditional alloy to the high-entropy alloy. CrNbTiZrV (Senkov, Acta Materialia,2013), NbMoTaWRe0.5C0.8(Wei,Scripta Materialia,2021)、HfNbTiZr OxThe comprehensive performance of the refractory high-entropy alloy such as (x is 0,1,2) (Lei, Nature,2018) is improved, but the contradiction between the room temperature brittleness and the high temperature strength is not solved, and the comprehensive mechanical performance of the room temperature and the high temperature is not solvedThe variety of excellent alloy systems is still quite short. In recent years, scholars at home and abroad apply a powder metallurgy process to the preparation of the high-entropy alloy. The nano second phase is introduced into the high-entropy alloy through the combination of mechanical alloying and spark plasma sintering process, and the composite oxide is generated in situ.

E.g., 8 vol.% Al2O3-Al0.4FeCrCo1.5NiTi0.3(Yang,Materials Chemistry and Physics,2018)、0~3vol.%Y2O3-Al0.3The combination property of high-entropy alloy such as CoCrFeMnNi alloy (Gwalani, script Materialia,2019) is improved. Such methods for adding a second phase are generally reported in the powder metallurgy process, but the alloy prepared by the powder metallurgy process inevitably has pores, and microcracks can be initiated near the pores, so that cracks are generated, and the performance of the alloy is influenced. Vacuum arc melting can effectively avoid the defect and obtain a uniform and compact structure. The process of vacuum arc melting with the addition of the second phase is expected to improve the comprehensive mechanical properties of the refractory high-entropy alloy. Chinese patent publication No. CN109338200B discloses that an alloy with excellent damping performance and mechanical properties is obtained by adding a ceramic phase in a TaNbHfZrTi alloy system by vacuum arc melting, which mainly introduces interstitial small atoms to achieve performance improvement. Chinese patent with publication number CN108504890A discloses that high-entropy alloy composite material with breaking strength of 2300 MPa-4000 MPa is obtained by adding ceramic phase in vacuum arc melting.

In conclusion, the element alloying is carried out on the basis of the existing refractory high-entropy alloy system so as to greatly improve the comprehensive mechanical property of the material in a wide temperature range, so that the difficulty is high, the alloy components are more complex, and the preparation cost is increased. Therefore, how to improve the existing optimization strategy of the refractory high-entropy alloy, and improve the room-temperature toughness of the alloy, and simultaneously ensure the high-temperature softening resistance of the alloy becomes a difficult problem to be solved urgently in the development process of the refractory high-entropy alloy.

Disclosure of Invention

The technical problem is as follows: the invention aims to provide a ceramic phase reinforced refractory high-entropy alloy composite material and a preparation method thereof.

The technical scheme is as follows: the invention adopts the following technical scheme: the ceramic phase reinforced refractory high-entropy alloy composite material comprises 4-6 refractory metal elements and a ceramic phase according to a certain atomic ratio, wherein the refractory metal elements are selected from W, Re, Ta, Mo, Nb, Hf, Zr, Ti, V and Cr; the atom percentage content of the refractory metal elements is a, and the a is more than or equal to 5% and less than or equal to 35%; the ceramic phase has the atomic percentage content of b, and b is more than or equal to 1% and less than or equal to 20%.

Further, the ceramic phase is selected from Al2O3、Y2O3、SiC、AlN、TiB2Any one or a combination of several of them.

Further, the preparation method of the ceramic phase reinforced refractory high-entropy alloy composite material comprises the following steps:

step 1: taking corresponding simple substance pure metal raw materials according to the types of alloy components, removing oxide skin, ultrasonically cleaning and drying, and accurately batching according to alloy components;

step 2: sequentially placing the weighed raw materials of the elements into a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, placing the ceramic phase at the bottommost part, and pumping the air pressure of a vacuum chamber of the vacuum arc melting furnace to 5 multiplied by 10-3Pa below;

and step 3: vacuum arc melting, wherein in order to ensure the uniformity of the alloy, the alloy is melted and then melted;

and 4, step 4: and cooling the ceramic phase-reinforced refractory high-entropy alloy composite material to room temperature in a vacuum chamber, taking out the ceramic phase-reinforced refractory high-entropy alloy composite material, and carrying out vacuum suction casting or vacuum casting to obtain the ceramic phase-reinforced refractory high-entropy alloy composite material.

Further, in the step 3, the time for melting each time after the alloy is melted is 160-200s, and each alloy ingot is melted 6-8 times to ensure the uniformity of the components.

Further, in the step 4, vacuum casting is adopted for performance improvement, specifically, the cast ingot is placed in a vacuum suction casting furnace, a casting mold is used, and vacuum pumping is carried out until the vacuum degree is 5 multiplied by 10-3And Pa, adopting 350-400A current to melt the ingot and then casting.

Further, it is characterized byIn the step 4, the vacuum suction casting process is adopted to obtain fine and uniform crystal grains, which is beneficial to improving the performance of the alloy, and specifically, the cast ingot is placed in a vacuum suction casting furnace, a suction casting mold is used, and the vacuum is pumped to 5 multiplied by 10-3Pa, the pressure difference is adjusted to 4 atmospheric pressures, and the ingot is melted by adopting 350-400A current and then is rapidly suction cast.

Has the advantages that: compared with the prior art, the ceramic phase reinforced refractory high-entropy alloy composite material is prepared by adding the ceramic phase and using a non-consumable vacuum arc melting furnace, and the obtained alloy has excellent room-temperature and high-temperature mechanical properties, the room-temperature yield strength is 2700-3500 MPa, the 800-DEG C yield strength is 1400-1700 MPa, and the alloy can still maintain 600-900 MPa at 1000 ℃. The preparation method of the invention has simple process and convenient operation; the alloy is of a single BCC structure, the microstructure appearance is mainly dendritic crystals, and interstitial atoms are introduced while a nano second phase is introduced, so that the average grain size is obviously reduced compared with that of a matrix refractory high-entropy alloy, the room temperature and high-temperature mechanical properties are obviously improved, and the alloy has excellent high-temperature structural stability at 800 ℃. The invention can obviously improve the service temperature of mechanical engineering equipment and parts, and is expected to replace nickel-based superalloy, thereby having wide application prospect in the fields of aerospace, transportation, petrochemical industry, mechanical electronics, automobile manufacturing and the like.

Drawings

FIG. 1 shows 97.8(HfNbTaTiV) -2.2Al2O3The X-ray diffraction pattern of the ceramic phase reinforced refractory high-entropy alloy composite material;

FIG. 2 shows 95.7(HfNbTaTiZrV) -4.3Al2O3The microstructure appearance of a scanning electron microscope of the ceramic phase reinforced refractory high-entropy alloy composite material is shown;

FIG. 3 shows 95.7(HfNbTaV) -4.3Al2O3The room temperature stress strain curve of the ceramic phase reinforced refractory high-entropy alloy composite material;

FIG. 4 shows 91.7(HfNbTaTiZrV) -8.3Al2O3The stress-strain curve at 800 ℃ of the ceramic phase reinforced refractory high-entropy alloy composite material;

FIG. 5 shows 91.7(HfNbTaTiZrV) -8.3Al2O3The stress-strain curve at 1000 ℃ of the ceramic phase reinforced refractory high-entropy alloy composite material.

FIG. 6 shows 88.5(HfNbTaTiZr) -5V-6.3Al2O3The room temperature stress strain curve of the ceramic phase reinforced refractory high-entropy alloy composite material;

FIG. 7 shows 55(HfNbTiZrV) -35Ta-10Al2O3The microstructure morphology of the room-temperature compression fracture scanning electron microscope of the ceramic phase reinforced refractory high-entropy alloy composite material.

Detailed Description

The present invention will be described in detail with reference to the following embodiments.

The ceramic phase reinforced refractory high-entropy alloy composite material is composed of 4-6 refractory metal elements and a small amount of ceramic phase added according to a certain atomic ratio, wherein the refractory high-entropy alloy matrix is 4-6 elements in W, Re, Ta, Mo, Nb, Hf, Zr, Ti, V and Cr, the atomic percent content is a, and a is more than or equal to 5% and less than or equal to 35%; the added ceramic phase comprises Al2O3、Y2O3、SiC、AlN、TiB2And the like. The content of atom percent is b, which satisfies that b is more than or equal to 1 percent and less than or equal to 20 percent.

A ceramic phase reinforced refractory high-entropy alloy composite material and a preparation method thereof are disclosed, wherein the refractory high-entropy alloy is introduced with a ceramic phase for reinforcement.

The content of the ceramic phase in atomic percent is b, and b is more than or equal to 1% and less than or equal to 20%.

The preparation method of the ceramic phase reinforced refractory high-entropy alloy composite material comprises the following steps:

step 1: taking corresponding simple substance pure metal raw materials according to the types of alloy components, removing oxide skin, ultrasonically cleaning and drying, and accurately batching according to alloy components;

step 2: sequentially placing the weighed raw materials of the elements into a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, placing the ceramic phase at the bottommost part, and pumping the air pressure of a vacuum chamber of the vacuum arc melting furnace to 5 multiplied by 10-3Pa below;

and step 3: arc melting, wherein in order to ensure the uniformity of the alloy, the melting time of each time after the alloy is melted is 160-200s, and each alloy ingot is melted for 6-8 times to ensure the uniformity of the components;

and 4, step 4: and cooling the ceramic phase-reinforced refractory high-entropy alloy composite material in a vacuum bin to room temperature, taking out the ceramic phase-reinforced refractory high-entropy alloy composite material, and carrying out suction casting or casting in a vacuum suction casting furnace to obtain the ceramic phase-reinforced refractory high-entropy alloy composite material.

Step 1, elemental powder is adopted to smelt elements with higher melting points, and the particle size is not limited.

After vacuum arc melting, the alloy has large segregation and uneven structure, and can be subjected to vacuum casting for improving the performance, specifically, a cast ingot is placed in a vacuum suction casting furnace, a casting mold is used, and the vacuum is pumped to 5 multiplied by 10-3And Pa, adopting 350-400A current to melt the ingot and then casting.

The vacuum suction casting process can obtain fine and uniform crystal grain structure and is favorable for improving the performance of alloy, and the process includes setting the ingot in a vacuum suction casting furnace, using a suction casting mold and vacuumizing to 5X 10-3Pa, the pressure difference is adjusted to 4 atmospheric pressures, and the ingot is melted by adopting 350-400A current and then is rapidly suction cast.

Example 1:

taking Al with the purity of 99.9 wt%2O3Particles and pure metal particles of Hf, Nb, Ta, Ti and V with the purity of not less than 99.95 wt.%, wherein the pure metal particles are mechanically polished to remove oxide skin, ultrasonically cleaned and blow-dried according to the formula of 97.8(HfNbTaTiV) -2.2Al2O3The materials are accurately mixed, and the mixture ratio is 19.56 at.% Hf, 19.56 at.% Nb, 19.56 at.% Ta, 19.56 at.% Ti, 19.56 at.% V, 2.2 at.% Al2O3. The weighed raw materials are sequentially distributed in a water-cooled copper mold crucible of a vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, and the ceramic phase is placed at the bottommost part. Before smelting, the furnace chamber is vacuumized to 5 x 10- 3Pa, and then filling argon to 0.7 atmosphere. During smelting, firstly smelting a titanium ingot in a furnace for 180s to remove residual oxygen in a furnace cavity; when the target alloy is melted, the alloy is kept for 180s after being completely melted. In order to obtain alloy ingots with uniform components, all samples are repeatedly smelted for 8 times, and the samples are turned over after each smelting. Followed by vacuum suction castingIn the furnace, the master alloy ingot is suction cast into a bar with the diameter of 10mm and the height of 60 mm. Cutting a small sample with the diameter of 10mm and the height of 1mm from the sample, grinding the surface of the sample by using sand paper, ultrasonically cleaning and drying the sample, and then carrying out an X-ray diffraction test on the sample. The detailed test parameters are that the scanning step length is 0.02 degree/s, the scanning speed is 4 degrees/min, and the scanning angle 2 theta range is 20-100 degrees. FIG. 1 shows 97.8(HfNbTaTiV) -2.2Al prepared from 97.8 atomic percent of refractory high-entropy alloy matrix and 2.2 atomic percent of ceramic phase2O3The X-ray diffraction pattern of the ceramic phase reinforced refractory high-entropy alloy composite material; the X-ray diffraction pattern of the ceramic phase reinforced refractory high-entropy alloy composite material prepared in the example 1 is shown in the attached figure 1. It can be seen that the ceramic phase reinforced refractory high-entropy alloy composite material prepared in example 1 has a single BCC structure, which indicates that it has a simple phase structure.

Example 2:

taking Al with the purity of 99.9 wt%2O3Particles and pure metal particles of Hf, Nb, Ta, Ti, Zr and V with the purity of not less than 99.95 wt.%, mechanically polishing the metal particles to remove oxide skin, ultrasonically cleaning and blow-drying the metal particles, and carrying out ultrasonic cleaning according to the formula of 95.7(HfNbTaTiZrV) -4.3Al2O3The materials are accurately mixed, and the mixture ratio is 15.95 at.% Hf, 15.95 at.% Nb, 15.95 at.% Ta, 15.95 at.% Ti, 15.95 at.% Zr, 15.95 at.% V and 4.3 at.% Al2O3. The weighed raw materials are sequentially distributed in a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, and the ceramic phase is placed at the bottommost part. Before smelting, the furnace chamber is vacuumized to 5 x 10-3Pa, and then filling argon to 0.7 atmosphere. During smelting, firstly smelting a titanium ingot in a furnace for 180s to remove residual oxygen in a furnace cavity; when the target alloy is smelted, the alloy is kept for 180s after being completely melted, alloy ingots with uniform components are not obtained, all samples are repeatedly smelted for 8 times, and the samples are turned over after each smelting. Then, the master alloy ingot is subjected to suction casting in a vacuum suction casting furnace to form a bar with the diameter of 10mm and the height of 60 mm. Cutting a rectangular thin sample with the diameter of 10mm and the height of 1mm from an alloy ingot by utilizing linear cutting, sequentially grinding, polishing, corroding, ultrasonically cleaning and drying, and observing alloy microscopy by utilizing a Sirion field emission scanning electron microscopeAnd (4) tissue morphology. The scanning electron micrograph of the ceramic phase reinforced refractory high-entropy alloy composite material prepared in the example 2 is shown in the attached figure 2; FIG. 2 shows 95.7(HfNbTaTiZrV) -4.3Al prepared from 95.7 atomic percent of refractory high-entropy alloy matrix and 4.3 atomic percent of ceramic phase2O3The microstructure appearance of the ceramic phase reinforced refractory high-entropy alloy composite material is a scanning electron microscope microstructure. As can be seen, the structure is compact, the structure morphology is typical dendrite, and no obvious pore, inclusion and crack exist, which shows that the ceramic phase reinforced refractory high-entropy alloy composite material has good casting performance.

Example 3:

taking Al with the purity of 99.9 wt%2O3Particles and pure metal particles of Hf, Nb, Ta, Ti, Zr and V with the purity of not less than 99.95 wt.%, wherein the pure metal particles are mechanically polished to remove oxide skin, ultrasonically cleaned and blow-dried according to the proportion of 95.7(HfNbTaV) -4.3Al2O3The materials are accurately mixed according to the mixture ratio of 23.93 at.% Hf, 23.92 at.% Nb, 23.92 at.% Ta, 23.93 at.% V and 4.3 at.% Al2O3. The weighed raw materials are sequentially distributed in a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, and the ceramic phase is placed at the bottommost part. Before smelting, the furnace chamber is vacuumized to 5 x 10-3Pa, and then filling argon to 0.7 atmosphere. During smelting, firstly smelting a titanium ingot in a furnace for 180s to remove residual oxygen in a furnace cavity; when the target alloy is smelted, the alloy is kept for 180s after being completely melted, alloy ingots with uniform components are not obtained, all samples are repeatedly smelted for 8 times, and the samples are turned over after each smelting. Then, the master alloy ingot is subjected to suction casting in a vacuum suction casting furnace to form a bar with the diameter of 10mm and the height of 1 mm. A cylindrical sample with the diameter of 2mm and the height of 4mm is cut from the middle part by utilizing linear cutting, the linear cutting trace on the bottom surface and the oxide skin on the side surface of the cylindrical sample are slightly ground by using 2000-mesh sand paper, and after ultrasonic cleaning and blow drying, the room temperature mechanical property of the alloy is tested by utilizing a Sans5305 type universal testing machine. FIG. 3 shows 95.7(HfNbTaV) -4.3Al prepared from 95.7 atomic percent of refractory high-entropy alloy matrix and 4.3 atomic percent of ceramic phase2O3The ceramic phase reinforced refractory high-entropy alloy composite material has a room temperature stress strain curve. Can seeAnd the yield strength of the ceramic phase reinforced refractory high-entropy alloy composite material is 2000MPa, the compressive strength is 3000MPa, and the fracture strain exceeds 20%. Compared with the reported refractory high-entropy alloy, the ceramic phase reinforced refractory high-entropy alloy composite material prepared in the embodiment has obviously improved room temperature strength, which shows that the ceramic phase reinforced refractory high-entropy alloy can realize the reinforcement of the material.

Example 4:

taking Al with the purity of 99.9 wt%2O3Particles and pure metal particles of Hf, Nb, Ta, Ti, Zr and V with the purity of not less than 99.95 wt.%, wherein the pure metal particles are mechanically polished to remove oxide skin, ultrasonically cleaned and blow-dried according to the proportion of 91.7(HfNbTaTiZrV) -8.3Al2O3The materials are accurately mixed, and the mixture ratio is 15.28 at.% Hf, 15.28 at.% Nb, 15.28 at.% Ta, 15.29 at.% Ti, 15.29 at.% Zr, 15.28 at.% V and 8.3 at.% Al2O3. The weighed raw materials are sequentially distributed in a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, and the ceramic phase is placed at the bottommost part. Before smelting, the furnace chamber is vacuumized to 5 x 10-3Pa, and then filling argon to 0.7 atmosphere. During smelting, firstly smelting a titanium ingot in a furnace for 180s to remove residual oxygen in a furnace cavity; when the target alloy is smelted, the alloy is kept for 180s after being completely melted, alloy ingots with uniform components are not obtained, all samples are repeatedly smelted for 8 times, and the samples are turned over after each smelting. Then, the master alloy ingot is subjected to suction casting in a vacuum suction casting furnace to form a bar with the diameter of 10mm and the height of 1 mm. A cylindrical sample with the diameter of 2mm and the height of 4mm is cut from the middle part by utilizing linear cutting, the linear cutting trace on the bottom surface and the oxide skin on the side surface of the cylindrical sample are slightly ground by using 2000-mesh sand paper, and after ultrasonic cleaning and blow drying, the room temperature mechanical property of the alloy is tested by utilizing a Sans5305 type universal testing machine provided with an electronic heating device. FIG. 4 is a stress-strain curve of the ceramic phase reinforced refractory high-entropy alloy composite material prepared in example 4 at 800 ℃ in an atmospheric environment, and FIG. 4 is 91.7(HfNbTaTiZrV) -8.3Al (HfNbTaTiZrV) prepared from a refractory high-entropy alloy matrix of 91.7 atomic percent and a ceramic phase of 8.3 atomic percent2O3The ceramic phase reinforced refractory high-entropy alloy composite material has a stress-strain curve at 800 ℃. Can seeThe yield strength of the ceramic phase reinforced refractory high-entropy alloy composite material is 1392MPa, and the fracture strain is greater than 20%, which shows that the ceramic phase reinforced refractory high-entropy alloy composite material has excellent comprehensive mechanical properties in a wide temperature range.

Example 5:

taking Al with the purity of 99.9 wt%2O3Particles and pure metal particles of Hf, Nb, Ta, Ti, Zr and V with the purity of not less than 99.95 wt.%, wherein the pure metal particles are mechanically polished to remove oxide skin, ultrasonically cleaned and blow-dried according to the proportion of 91.7(HfNbTaTiZrV) -8.3Al2O3The materials are accurately mixed, and the mixture ratio is 15.28 at.% Hf, 15.28 at.% Nb, 15.28 at.% Ta, 15.29 at.% Ti, 15.29 at.% Zr, 15.28 at.% V and 8.3 at.% Al2O3. The weighed raw materials are sequentially distributed in a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, and the ceramic phase is placed at the bottommost part. Before smelting, the furnace chamber is vacuumized to 5 x 10-3Pa, and then filling argon to 0.7 atmosphere. During smelting, firstly smelting a titanium ingot in a furnace for 180s to remove residual oxygen in a furnace cavity; when the target alloy is smelted, the alloy is kept for 180s after being completely melted, alloy ingots with uniform components are not obtained, all samples are repeatedly smelted for 8 times, and the samples are turned over after each smelting. Then, the master alloy ingot is subjected to suction casting in a vacuum suction casting furnace to form a bar with the diameter of 10mm and the height of 1 mm. A cylindrical sample with the diameter of 2mm and the height of 4mm is cut from the middle part by utilizing linear cutting, the linear cutting trace on the bottom surface and the oxide skin on the side surface of the cylindrical sample are slightly ground by using 2000-mesh sand paper, and after ultrasonic cleaning and blow drying, the room temperature mechanical property of the alloy is tested by utilizing a Sans5305 type universal testing machine provided with an electronic heating device. FIG. 5 shows 91.7(HfNbTaTiZrV) -8.3Al prepared from 91.7 atomic percent of refractory high-entropy alloy matrix and 8.3 atomic percent of ceramic phase2O3The stress-strain curve at 1000 ℃ of the ceramic phase reinforced refractory high-entropy alloy composite material.

FIG. 5 is a stress-strain curve of the ceramic phase reinforced refractory high-entropy alloy composite material prepared in example 5at 1000 ℃ in an atmospheric environment. It can be seen that the yield strength of the ceramic phase reinforced refractory high-entropy alloy composite material is 693MPa, and the fracture strain is greater than 20%, which shows that the ceramic phase reinforced refractory high-entropy alloy composite material has excellent comprehensive mechanical properties in a wide temperature range.

Example 6:

taking Al with the purity of 99.9 wt%2O3Particles and pure metal particles of Hf, Nb, Ta, Ti, Zr and V with the purity of not less than 99.95 wt.%, wherein the pure metal particles are mechanically ground to remove oxide skin, ultrasonically cleaned and blow-dried according to the proportion of 88.5(HfNbTaTiZr) -5V-6.3Al2O3The materials are accurately mixed, and the mixture ratio is 17.7 at.% Hf, 17.7 at.% Nb, 17.7 at.% Ta, 17.7 at.% Ti, 17.7 at.% Zr, 5 at.% V, and 6.3 at.% Al2O3. The weighed raw materials are sequentially distributed in a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, and the ceramic phase is placed at the bottommost part. Before smelting, the furnace chamber is vacuumized to 5 x 10-3Pa, and then filling argon to 0.7 atmosphere. During smelting, firstly smelting a titanium ingot in a furnace for 180s to remove residual oxygen in a furnace cavity; when the target alloy is smelted, the alloy is kept for 180s after being completely melted, alloy ingots with uniform components are not obtained, all samples are repeatedly smelted for 8 times, and the samples are turned over after each smelting. Then, the master alloy ingot is subjected to suction casting in a vacuum suction casting furnace to form a bar with the diameter of 10mm and the height of 1 mm. A cylindrical sample with the diameter of 2mm and the height of 4mm is cut from the middle part by utilizing linear cutting, the linear cutting trace on the bottom surface and the oxide skin on the side surface of the cylindrical sample are slightly ground by using 2000-mesh sand paper, and after ultrasonic cleaning and blow drying, the room temperature mechanical property of the alloy is tested by utilizing a Sans5305 type universal testing machine provided with an electronic heating device. FIG. 6 shows 88.5(HfNbTaTiZr) -5V-6.3Al prepared from 93.5 atomic% of refractory high-entropy alloy matrix and 6.3 atomic% of ceramic phase2O3The ceramic phase reinforced refractory high-entropy alloy composite material has a room temperature stress strain curve. FIG. 6 is a stress-strain curve of the ceramic phase reinforced refractory high-entropy alloy composite material prepared in example 6 in a room temperature environment. It can be seen that the yield strength of the ceramic phase reinforced refractory high-entropy alloy composite material is 2200MPa, and the fracture strain is obviously reduced, which shows that the ceramic phase reinforced refractory high-entropy alloy composite material with high V content has more excellent comprehensive mechanical properties at room temperature.

Example 7:

taking Al with the purity of 99.9 wt%2O3Particles and pure metal particles of Hf, Nb, Ta, Ti, Zr and V with the purity of not less than 99.95 wt.%, wherein the pure metal particles are mechanically polished to remove oxide skin, ultrasonically cleaned and blow-dried according to the formula of 55(HfNbTiZrV) -35Ta-10Al2O3The materials are accurately mixed according to the mixture ratio of 11 at.% Hf, 11 at.% Nb, 35 at.% Ta, 11 at.% Ti, 11 at.% Zr, 11 at.% V and 10 at.% Al2O3. The weighed raw materials are sequentially distributed in a water-cooled copper mold crucible of a non-consumable vacuum arc melting furnace according to the sequence of the melting points of the elements from low to high, and the ceramic phase is placed at the bottommost part. Before smelting, the furnace chamber is vacuumized to 5 x 10-3Pa, and then filling argon to 0.7 atmosphere. During smelting, firstly smelting a titanium ingot in a furnace for 180s to remove residual oxygen in a furnace cavity; when the target alloy is smelted, the alloy is kept for 180s after being completely melted, alloy ingots with uniform components are not obtained, all samples are repeatedly smelted for 8 times, and the samples are turned over after each smelting. Then, the master alloy ingot is subjected to suction casting in a vacuum suction casting furnace to form a bar with the diameter of 10mm and the height of 1 mm. A cylindrical sample with the diameter of 2mm and the height of 4mm is cut from the middle part by utilizing linear cutting, the linear cutting trace on the bottom surface and the oxide skin on the side surface of the cylindrical sample are slightly ground by using 2000-mesh sand paper, and after ultrasonic cleaning and blow drying, the room temperature mechanical property of the alloy is tested by utilizing a Sans5305 type universal testing machine provided with an electronic heating device. FIG. 7 shows 55(HfNbTiZrV) -35Ta-10Al prepared from 93.5 atomic% of refractory high-entropy alloy matrix and 6.3 atomic% of ceramic phase2O3The microstructure morphology of the room-temperature compression fracture scanning electron microscope of the ceramic phase reinforced refractory high-entropy alloy composite material.

FIG. 7 shows the microstructure morphology of the room-temperature compressive fracture scanning electron microscope of the ceramic phase-reinforced refractory high-entropy alloy composite material prepared in example 7. It can be seen that the high-Ta-content ceramic phase reinforced refractory high-entropy alloy composite material does not show a complete brittle fracture morphology, and the fracture surface still has a part of tough dimple morphology, which indicates that the plasticity of the alloy is not completely sacrificed when the strength of the high-Ta-content ceramic phase reinforced refractory high-entropy alloy composite material is improved.

The above embodiments are merely illustrative of the features and contents of the present invention, and the scope of the present invention is not limited thereto, and the contents of the claims of the present invention are subject to the claims. Any modification or variation made in accordance with the spirit of the present invention falls within the scope of the present invention.

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