Alkali-corrosion-resistant high-entropy alloy bonded metal ceramic and preparation method thereof

Abstract

The invention discloses alkali-corrosion-resistant high-entropy alloy bonded metal ceramic, which is prepared from the following raw materials in percentage by mass: 54.5 to 70 percent of hard phase: (Ti, W) C and 25 to 30 percent of bonding phase, and the bonding phase is one of CoCrFeNiMo, CoCrFeNiAl, CoCrFeNiAl 0.1, CoCrFeNi, CoCrFeNiMn and CoCrFeNiMo 0.2. The invention further discloses a preparation method of the alkali-corrosion-resistant high-entropy alloy bonded metal ceramic. The prepared metal ceramic sample and other ceramic systems reported in literatures show lower corrosion current density and higher corrosion potential in an alkaline solution. Compared with metal ceramic with Ni / Co, Ni / Cr and Ni3Al as binders, the metal ceramic in the research shows better corrosion resistance in an alkaline environment.

Description

Technical Field

[0001] The present invention relates to the field of metal ceramics, and in particular to an alkali corrosion resistant high entropy alloy bonded metal ceramic and a preparation method thereof. Background Art

[0002] With the continuous advancement of science and technology, the demand for high-performance, multifunctional cermets is increasing. Traditional cermets are often limited by their corrosion resistance. High-entropy alloys, as a new class of materials, have become a focus of attention in the current field of materials research due to their unique atomic structure and multi-element composition. (Ti, W) C-based cermets are widely used in high-speed cutting and wear-resistant applications, with advantages such as excellent hardness, wear resistance, and a low friction coefficient with metals. However, in more harsh working conditions such as petrochemicals, mining, chemical fibers, and metallurgy, traditional cermets still face problems such as corrosion leading to component failure and damage, which limits their application in these specialized fields. Drill bits, drill pipes, and other drilling tools used in oil drilling and mining operations are highly susceptible to corrosion when exposed to alkaline drilling fluids for long periods of time, and valves and sealing components in chemical manufacturing are exposed to high pH environments. Therefore, it is necessary to provide a method for preparing corrosion-resistant CoCrFeNiM high-entropy alloy-bonded (Ti, W) C-based cermets to overcome the corrosion resistance limitations of traditional materials and meet the needs of a wider range of fields. This method not only requires improving the comprehensive properties of metal ceramics, but also requires reducing the cost of the preparation process and improving production efficiency in order to be more competitive in the market.

[0003] The present invention aims to solve the problem of low corrosion resistance of traditional metal ceramics and provide an innovative preparation method of corrosion-resistant high-entropy alloy-bonded (Ti, W)C-based metal ceramics, so that they have superior mechanical properties and high-temperature stability, and can achieve significant advantages in a series of application scenarios. Summary of the Invention

[0004] To solve the above problems, the present invention aims to provide an alkali-corrosion-resistant high-entropy alloy bonded metal ceramic and a preparation method thereof, wherein the metal ceramic can obtain a lower corrosion current density and a higher corrosion potential through a selected formula and ratio.

[0005] The present invention is achieved through the following technical solutions:

[0006] An alkali corrosion resistant high entropy alloy bonded metal ceramic, the raw materials used include 54.5% to 70% hard phase (Ti, W) C, 25-30% bonding phase, the bonding phase is CoCrFeNiMo, CoCrFeNiAl, CoCrFeNiAl 0.1 , CoCrFeNi, CoCrFeNiMn, CoCrFeNiMo0.2 One of them.

[0007] By mass, it also includes a first additional phase: 5% Ni, 0.5% Cr3C2, and 1.5%-15% TiN.

[0008] The second additional phase is also included: 10% TiN by mass.

[0009] In terms of mass, it also includes a third additional phase: 10% TiN and 3% Nb.

[0010] The cermet also includes a fourth additive phase, 10% nano-WC, by mass. In the embodiment, the TiN is at the micron or nanometer level. Micron-level particles are 2-10 microns, while nano-level particles are 20-30 nanometers. Nano-WC particles are 40-50 nanometers. Different particle sizes affect the corrosion resistance of the cermet.

[0011] The self-corrosion current density of the alkali-resistant high-entropy alloy binder phase cermet is 0.169-2.841 μA / cm 2 , self-corruption

[0012] The corrosion potential is -0.233~-0.183V.

[0013] A method for preparing an alkali-corrosion-resistant high-entropy alloy-bonded metal ceramic comprises the following steps: 1) prefabricating high-entropy alloy powder; 2) ball milling the ingredients: weighing and ball milling the prefabricated high-entropy alloy powder, hard phase and additive phase powder according to component requirements, then pressing them into blanks, and then sintering them.

[0014] The particle size of the powders of Co, Cr, Fe, Ni, etc. in step 1 is 2 to 5 μm, and the purity is ≥99.9%.

[0015] In step 1), high entropy alloy preformed powder is prepared by mechanical alloying: the process parameters of mechanical alloying are: ball-to-material ratio is 15:1, of which small balls are 50%, medium balls are 20%, and large balls are 30%. The ball mill speed is 350 rpm, the ball mill tank is filled with Ar gas protective atmosphere, the total ball milling time is 60 hours, and every 60 minutes, it stops for 15 minutes to cool down.

[0016] The sintering process parameters in step 4 are: sintering temperature of 1450-1550°C, heating rate of 5°C / min, and holding time of 60-180min. The present invention reduces the porosity of the cermet and improves the density by optimizing the high-temperature sintering process, while suppressing the abnormal growth of ceramic grains, promoting the uniform distribution of the ceramic phase and the binder phase, and regulating the content of alloying elements in the binder phase. By enhancing the density of the cermet surface and regulating the composition and relative content of corrosion products in the passivation film, the penetration of the corrosive medium is effectively prevented, thereby reducing the corrosion current density and improving the overall corrosion resistance of the cermet.

[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0018] The metal ceramic samples prepared in the present invention exhibit lower corrosion current density and higher corrosion potential in alkaline environments, especially in strong alkaline solutions such as sodium hydroxide, compared to other ceramic systems reported in the literature. Compared with the metal ceramics with Ni / Co, Ni / Cr and Ni3Al as binders in the literature, the metal ceramics in this study exhibit better corrosion resistance in alkaline environments. During the corrosion process, the passivating elements in the binder phase will form a large amount of corrosion products on the surface of the metal ceramic, such as TiO2, Cr2O3, Fe(OH)3, NiO, Ni(OH)2 and MoO3. These corrosion products are components of the passivation film, which adheres to the surface of the metal ceramic to form a dense protective film. This prevents the corrosion process and protects the corrosive solution from further damage to the metal ceramic matrix. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0020] Figure 1 This is a potentiodynamic polarization curve of the metal ceramic of Example 3 of the present invention in 1 mol / L NaOH solution.

[0021] Figure 2 This is a potentiodynamic polarization curve of the metal ceramic of Example 4 of the present invention in 1 mol / L NaOH solution. DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0023] Example 1

[0024] A (Ti, W)C-based cermet material having a high-entropy alloy binder phase with excellent corrosion resistance, comprising the following components, expressed in percentage by mass:

[0025] (Ti, W)C 57%;

[0026] CoCrFeNiMo 25%;

[0027] Ni 5%;

[0028] Cr3C2 0.5%;

[0029] micron-TiN 12.5%;

[0030] The method for preparing the (Ti, W)C-based cermet material having a CoCrFeNiMo high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0031] (1) Prefabrication of CoCrFeNiMo high entropy alloy powder: High-purity Co, Cr, Fe, Ni, and Mo powders (particle size of 2-5 μm, purity ≥99.5%) were weighed and mixed according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNiMo high entropy alloy prefabricated powder. The process parameters of mechanical alloying were as follows: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls, and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, with a 15-minute cooling stop every 60 minutes.

[0032] (2) Ball milling: The required high entropy alloy powder, hard phase and additive phase powder are weighed and mixed according to the composition requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium of anhydrous ethanol;

[0033] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, the sintering temperature is 1450℃, the heating rate is 5℃ / min, and the holding time is 60min.

[0034] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiMo high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0035] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 1.

[0036] Table 1 Electrochemical corrosion parameters of the metal ceramics prepared in Example 1

[0037] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 1# 2.509 -0.232

[0038] Example 2

[0039] A (Ti, W)C-based cermet material with a CoCrFeNiMo high-entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0040] (Ti, W)C 54.5%;

[0041] CoCrFeNiMo 25%;

[0042] Ni 5%;

[0043] Cr3C2 0.5%;

[0044] micron-TiN 15%;

[0045] The method for preparing the (Ti, W)C-based cermet material having a CoCrFeNiMo high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0046] (1) Prefabrication of CoCrFeNiMo high entropy alloy powder: High-purity Co, Cr, Fe, Ni, and Mo powders (particle size of 2-5 μm, purity ≥99.5%) were weighed and mixed according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNiMo high entropy alloy prefabricated powder. The process parameters of mechanical alloying were as follows: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls, and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, with a 15-minute cooling stop every 60 minutes.

[0047] (2) Ball milling: The required high entropy alloy powder, hard phase and additive phase powder are weighed and mixed according to the composition requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, ball milling medium of anhydrous ethanol; micron-TiN is 10 microns;

[0048] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1400℃, heating rate is 5℃ / min, and holding time is 60min.

[0049] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiMo high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0050] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 2.

[0051] Table 2 Electrochemical corrosion parameters of the metal ceramics prepared in Example 2

[0052] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 2# 2.318 -0.224

[0053] Example 3

[0054] A (Ti, W)C-based cermet material with a CoCrFeNiMo high-entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0055] (Ti, W)C 68%;

[0056] CoCrFeNiMo 25%;

[0057] Ni 5%;

[0058] Cr3C2 0.5%;

[0059] nano-TiN 1.5%;

[0060] The method for preparing the (Ti, W)C-based cermet material having a CoCrFeNiMo high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0061] (1) Prefabrication of CoCrFeNiMo high entropy alloy powder: High-purity Co, Cr, Fe, Ni, and Mo powders (particle size of 2-5 μm, purity ≥99.5%) were weighed and mixed according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNiMo high entropy alloy prefabricated powder. The process parameters of mechanical alloying were as follows: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls, and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, with a 15-minute cooling stop every 60 minutes.

[0062] (2) Ball milling: The required high entropy alloy powder, hard phase and additive phase powder are weighed and mixed according to the component requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio is 7:1, the speed of the ball mill is 200 rpm, the ball milling medium is anhydrous ethanol; the nano-TiN is 20 nanometers.

[0063] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1400℃, heating rate is 5℃ / min, and holding time is 60min.

[0064] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiMo high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase. Figure 1 This is the potentiodynamic polarization curve of the metal ceramic of Example 3 in 1 mol / L NaOH solution, indicating that the metal ceramic prepared in Example 3 has good corrosion resistance.

[0065] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 3.

[0066] Table 3 Electrochemical corrosion parameters of the metal ceramics prepared in Example 3

[0067] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 3# 2.296 -0.233

[0068] Example 4

[0069] A (Ti, W)C-based cermet material with a CoCrFeNiMo high-entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0070] (Ti, W)C 67%;

[0071] CoCrFeNiMo 25%;

[0072] Ni 5%;

[0073] Cr3C2 0.5%;

[0074] nano-TiN 2.5%;

[0075] The method for preparing the (Ti, W)C-based cermet material having a CoCrFeNiMo high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0076] (1) Prefabrication of CoCrFeNiMo high entropy alloy powder: High-purity Co, Cr, Fe, Ni, and Mo powders (particle size of 2-5 μm, purity ≥99.5%) were weighed and mixed according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNiMo high entropy alloy prefabricated powder. The process parameters of mechanical alloying were as follows: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls, and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, with a 15-minute cooling stop every 60 minutes.

[0077] (2) Ball milling: The required high entropy alloy powder, hard phase and additive phase powder are weighed and mixed according to the composition requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium of anhydrous ethanol;

[0078] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1400℃, heating rate is 5℃ / min, holding time is 60min. Nano-TiN is 30nm.

[0079] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiMo high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase. Figure 2 3 is the potentiodynamic polarization curve of the metal ceramic of Example 4 in 1 mol / L NaOH solution, which shows that the metal ceramic of Example 4 has good corrosion resistance in an alkaline environment.

[0080] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 4.

[0081] Table 4 Electrochemical corrosion parameters of the metal ceramics prepared in Example 4

[0082] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 4# 1.619 -0.216

[0083] Example 5

[0084] A (Ti, W) C-based cermet material with a CoCrFeNi high entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0085] (Ti,W)C 70%;

[0086] CoCrFeNi 30%;

[0087] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNi high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0088] (1) Prefabrication of CoCrFeNi high entropy alloy powder: High-purity Co, Cr, Fe, and Ni powders (particle size 2-5 μm, purity ≥99.5%) were weighed and mixed according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNi high entropy alloy prefabricated powder. The process parameters for mechanical alloying were as follows: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls, and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, with a 15-minute cooling stop every 60 minutes.

[0089] (2) Ball milling: The required high entropy alloy powder and hard phase powder are weighed and mixed according to the composition requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium is anhydrous ethanol;

[0090] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, the sintering temperature is 1550℃, the heating rate is 5℃ / min, and the holding time is 60min.

[0091] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNi high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0092] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 5.

[0093] Table 5 Electrochemical corrosion parameters of the metal ceramics prepared in Example 5

[0094] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 5# 1.798 -0.191

[0095] Example 6

[0096] A (Ti, W) C-based cermet material with a CoCrFeNiAl high entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0097] (Ti,W)C 70%;

[0098] CoCrFeNiAl 30%;

[0099] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNiAl high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0100] (1) Prefabrication of CoCrFeNiAl high entropy alloy powder: Weigh and mix high-purity Co, Cr, Fe, Ni and Al powders (particle size of 2-5 μm, purity ≥99.5%) according to the composition requirements, place the mixed powder in a stainless steel ball mill, and prepare CoCrFeNiAl high entropy alloy prefabricated powder by mechanical alloying. The process parameters of mechanical alloying are: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls, and 30% large balls. The ball mill speed is 350 rpm, and the ball mill is filled with Ar gas protective atmosphere. The total ball milling time is 60 hours, and every 60 minutes, stop for 15 minutes to cool down. (2) Ball milling: Weigh and mix the required high entropy alloy powder and hard phase powder according to the composition requirements, and then place the mixture in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium is anhydrous ethanol.

[0101] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, the sintering temperature is 1550℃, the heating rate is 5℃ / min, and the holding time is 60min.

[0102] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiAl high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0103] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 6.

[0104] Table 6 Electrochemical corrosion parameters of the metal ceramics prepared in Example 6

[0105] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 6# 2.978 -0.181

[0106] Example 7

[0107] A CoCrFeNiAl alloy with excellent corrosion resistance 0.1 The (Ti, W)C-based cermet material of the high entropy alloy binder phase comprises the following components in percentage by mass:

[0108] (Ti, W)C 70%;

[0109] CoCrFeNiAl 0.1 30%;

[0110] The above-mentioned CoCrFeNiAl 0.1 A method for preparing a (Ti, W)C-based cermet material with a high entropy alloy binder phase comprises the following steps:

[0111] (1) Ball milling: The prepared high entropy alloy powder and hard phase powder were weighed and mixed according to the composition requirements, and then the mixture was placed in a planetary ball mill for wet milling. The process parameters of wet milling were: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium of anhydrous ethanol;

[0112] (2) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1400℃, heating rate is 5℃ / min, and holding time is 60min.

[0113] (3) Cooling treatment after sintering: The cooling method is to cool the furnace at a cooling rate of 5℃ / min to improve the CoCrFeNiAl 0.1 The strength and plasticity of the high entropy alloy binder phase and the improvement of the interface bonding between the high entropy alloy and the hard phase.

[0114] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 7.

[0115] Table 7 Electrochemical corrosion parameters of the metal ceramics prepared in Example 7

[0116] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 7# 2.434 -0.191

[0117] Example 8

[0118] A (Ti, W)C-based cermet material with a CoCrFeNiAl high-entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0119] (Ti, W)C 70%;

[0120] CoCrFeNiAl 30%;

[0121] The method for preparing the (Ti, W)C-based cermet material having a CoCrFeNiAl high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0122] (1) Ball milling: The prepared high entropy alloy powder and hard phase powder were weighed and mixed according to the composition requirements, and then the mixture was placed in a planetary ball mill for wet milling. The process parameters of wet milling were: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium of anhydrous ethanol;

[0123] (2) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1400℃, heating rate is 5℃ / min, and holding time is 120min.

[0124] (3) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiAl high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0125] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 8.

[0126] Table 8 Electrochemical corrosion parameters of the metal ceramics prepared in Example 8

[0127] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 8# 2.841 -0.186

[0128] Embodiment 9

[0129] A (Ti, W)C-based cermet material with a CoCrFeNiAl high-entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0130] (Ti, W)C 70%;

[0131] CoCrFeNiAl 30%;

[0132] The method for preparing the (Ti, W)C-based cermet material having a CoCrFeNiAl high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0133] (1) Ball milling: The prepared high entropy alloy powder and hard phase powder were weighed and mixed according to the composition requirements, and then the mixture was placed in a planetary ball mill for wet milling. The process parameters of wet milling were: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium of anhydrous ethanol;

[0134] (2) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1400℃, heating rate is 5℃ / min, and holding time is 180min.

[0135] (3) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiAl high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0136] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 9.

[0137] Table 9 Electrochemical corrosion parameters of the metal ceramics prepared in Example 9

[0138] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 9# 2.794 -0.183

[0139] Example 10

[0140] A (Ti, W) C-based cermet material with a CoCrFeNiMn high entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0141] TiC 70%;

[0142] TiN 10%;

[0143] CoCrFeNiMn 20%;

[0144] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNiMn high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0145] (1) Ball milling: The prepared high entropy alloy powder, hard phase and additive phase powder are weighed and mixed according to the composition requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium of anhydrous ethanol;

[0146] (2) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1450℃, heating rate is 5℃ / min, holding time is 60min. Nano-TiN is 20nm.

[0147] (3) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiMn high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0148] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 9.

[0149] Table 10 Electrochemical corrosion parameters of the metal ceramics prepared in Example 10

[0150] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 10# 3.126 -0.355

[0151] Example 11

[0152] A (Ti, W) C-based cermet material with a CoCrFeNi high entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0153] TiC 60%;

[0154] TiN 10%;

[0155] CoCrFeNiMn 27%;

[0156] Nb 3%;

[0157] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNi high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0158] (1) Prefabrication of CoCrFeNi high entropy alloy powder: High-purity Co, Cr, Fe and Ni powders (particle size of 2-5 μm, purity ≥99.5%) were weighed and prepared according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNi high entropy alloy prefabricated powder. The process parameters of mechanical alloying were: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, and every 60 minutes, it was stopped for 15 minutes to cool down. (2) Ball milling: The required high entropy alloy powder, hard phase and additive phase powders were weighed and prepared according to the composition requirements. The mixture was then placed in a planetary ball mill for wet milling. The process parameters of wet milling were: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and anhydrous ethanol as the ball milling medium.

[0159] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10-3 Pa, sintering temperature is 1420℃, heating rate is 5℃ / min, holding time is 60min. Nano-TiN is 20nm.

[0160] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNi high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0161] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 11.

[0162] Table 11 Electrochemical corrosion parameters of the metal ceramics prepared in Example 11

[0163] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 11# 3.715 -0.171

[0164] Example 12

[0165] A (Ti, W) C-based cermet material with a CoCrFeNiMo high entropy alloy binder phase having excellent corrosion resistance, comprising the following components in percentage by mass:

[0166] (Ti,W)C 60%;

[0167] nano-WC 10%;

[0168] CoCrFeNiMo 0.2 30%;

[0169] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNiMo high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0170] (1) Ball milling: The prepared high entropy alloy powder, hard phase and additive phase powder are weighed and mixed according to the component requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio is 7:1, the speed of the ball mill is 200 rpm, the ball milling medium is anhydrous ethanol; the nano-WC is 50 nanometers.

[0171] (2) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1450℃, heating rate is 5℃ / min, and holding time is 60min.

[0172] (3) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiMo high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0173] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 12.

[0174] Table 12 Electrochemical corrosion parameters of the cermets prepared in Example 12

[0175] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 12# 3.653 -0.211

[0176] Comparative Example 1

[0177] Similar to Example 1, the difference is that the bonding phase is FeCoCrNiMo of equal mass.

[0178] A (Ti, W) C-based cermet material with a CoCrFeNiMo high entropy alloy binder phase having excellent corrosion resistance, comprising the following components in percentage by mass:

[0179] (Ti,W)C 69.5%;

[0180] CoCrFeNiMo 25%;

[0181] Ni 5%;

[0182] Cr3C2 0.5%;

[0183] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNiMo high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0184] (1) Prefabrication of CoCrFeNiMo high entropy alloy powder: High-purity Co, Cr, Fe, Ni, and Mo powders (particle size 2-5 μm, purity ≥99.5%) were weighed and mixed according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNiMo high entropy alloy prefabricated powder. The process parameters for mechanical alloying were as follows: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls, and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, with a 15-minute cooling stop every 60 minutes.

[0185] (2) Ball milling: The required high entropy alloy powder, hard phase and additive phase powder are weighed and mixed according to the composition requirements, and then the mixture is placed in a planetary ball mill for wet milling. The process parameters of wet milling are: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and ball milling medium is anhydrous ethanol;

[0186] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, sintering temperature is 1450℃, heating rate is 5℃ / min, and holding time is 60min.

[0187] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNiMo high-entropy alloy binder phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0188] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 13.

[0189] Table 13 Electrochemical corrosion parameters of the metal ceramics prepared in Comparative Example 1

[0190] Element Corrosion current density (μA / cm2) Corrosion potential (V) Comparative Example 1 4.859 -0.248

[0191] Comparative Example 2

[0192] A (Ti, W) C-based cermet material with a CoCrFeNi high entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0193] (Ti,W)C 70%;

[0194] CoCrFeNi 30%;

[0195] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNi high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0196] (1) Prefabrication of CoCrFeNi high entropy alloy powder: High-purity Co, Cr, Fe and Ni powders (particle size of 2-5 μm, purity ≥99.5%) were weighed and prepared according to the composition requirements. The mixed powders were placed in a stainless steel ball mill and mechanically alloyed to prepare CoCrFeNi high entropy alloy prefabricated powder. The process parameters of mechanical alloying were: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, and every 60 minutes, it was stopped for 15 minutes to cool down. (2) Ball milling: The required medium entropy alloy powder, hard phase and additive phase powders were weighed and prepared according to the composition requirements. The mixture was then placed in a planetary ball mill for wet milling. The process parameters of wet milling were: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and anhydrous ethanol as the ball milling medium.

[0197] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, the sintering temperature is 1350℃, the heating rate is 5℃ / min, and the holding time is 60min.

[0198] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNi high-entropy alloy bonding phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0199] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 14.

[0200] Table 14 Electrochemical corrosion parameters of the metal ceramics prepared in Comparative Example 2

[0201] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 11# 23.841 -0.483

[0202] Comparative Example 3

[0203] A (Ti, W) C-based cermet material with a CoCrFeNiAl high entropy alloy binder phase having excellent corrosion resistance, comprising the following components, expressed in mass percentage:

[0204] (Ti,W)C 70%;

[0205] CoCrFeNi 30%;

[0206] The method for preparing the (Ti, W) C-based cermet material having a CoCrFeNiAl high entropy alloy binder phase with excellent corrosion resistance comprises the following steps:

[0207] (1) Prefabrication of CoCrFeNi high entropy alloy powder: High-purity Co, Cr, Fe, Ni and Al powders (particle size of 2-5 μm, purity ≥99.5%) were weighed and prepared according to the composition requirements. The mixed powder was placed in a stainless steel ball mill and mechanical alloying was used to prepare CoCrFeNi high entropy alloy prefabricated powder. The process parameters of mechanical alloying were: ball-to-material ratio of 15:1, with 50% small balls, 20% medium balls and 30% large balls. The ball mill speed was 350 rpm, and the ball mill was filled with Ar gas protective atmosphere. The total ball milling time was 60 hours, and every 60 minutes, it was stopped for 15 minutes to cool down. (2) Ball milling: The required medium entropy alloy powder, hard phase and additive phase powder were weighed and prepared according to the composition requirements. The mixture was then placed in a planetary ball mill for wet milling. The process parameters of wet milling were: ball-to-material ratio of 7:1, ball mill speed of 200 rpm, and anhydrous ethanol as the ball milling medium.

[0208] (3) Metal ceramic sintering: The slurry after ball milling is dried in an oven, and then the dried powder is put into a graphite mold and sintered in a tube furnace in vacuum to obtain a metal ceramic material. The sintering process parameters are: vacuum degree 10 -3 Pa, the sintering temperature is 1550℃, the heating rate is 5℃ / min, and the holding time is 360min.

[0209] (4) Post-sintering cooling treatment: The cooling method is furnace cooling at a cooling rate of 5°C / min to enhance the strength and plasticity of the CoCrFeNi high-entropy alloy bonding phase and improve the interface bonding between the high-entropy alloy and the hard phase.

[0210] The material obtained in this example was subjected to a 2h electrochemical corrosion test, and the test results are shown in Table 15.

[0211] Table 15 Electrochemical corrosion parameters of the metal ceramics prepared in Comparative Example 3

[0212] Element <![CDATA[Corrosion current density (μA / cm 2 )]]> Corrosion potential (V) 11# 6.745 -0.283

[0213] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An alkali corrosion resistant high entropy alloy bonded metal ceramic, characterized in that: By mass, the raw materials used are It contains 54.5% to 70% hard phase (Ti, W) C, 25-30% bonding phase, and the bonding phase is CoCrFeNiMo, CoCrFeNiAl, CoCrFeNiAl 0.1 , CoCrFeNi, CoCrFeNiMn, CoCrFeNiMo 0.2 One of them.

2. The alkali corrosion resistant high entropy alloy bonded cermet according to claim 1, characterized in that: By mass, it also includes a first additional phase: 5% Ni, 0.5% Cr3C2, and 1.5%-15% TiN.

3. The alkali corrosion resistant high entropy alloy bonded cermet according to claim 1, characterized in that: The second additional phase is also included: 10% TiN by mass.

4. The alkali corrosion resistant high entropy alloy bonded cermet according to claim 1, characterized in that: The third additional phase is also included by mass: 10% TiN and 3% Nb.

5. The alkali corrosion resistant high entropy alloy bonded cermet according to claim 1, characterized in that: The fourth additional phase is also included: 10% nano-WC by mass.

6. The alkali corrosion resistant high entropy alloy bonded cermet according to claim 1, characterized in that: The self-corrosion current density of the alkali-resistant high entropy alloy binder phase metal ceramic is 0.169-2.841 μA / cm 2 , the self-corrosion potential is -0.233~-0.183V.

7. The method for preparing an alkali corrosion resistant high entropy alloy bonded metal ceramic according to claim 1, wherein The method comprises the following steps: 1) prefabricating high entropy alloy powder; 2) ball milling the ingredients: weighing and ball milling the prefabricated high entropy alloy powder and other raw materials according to component requirements, and then pressing them into blanks, and then sintering them.

8. The preparation method according to claim 4, characterized in that The particle size of the binder phase element powder in step 1 is 2 to 5 μm, and the purity is ≥99.9%.

9. The preparation method according to claim 4, characterized in that The sintering process parameters in step 4 are: sintering temperature of 1450-1550° C., heating rate of 5° C. / min, and holding time of 60-180 min.

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