Seawater abrasion and corrosion resistant carbide sintered body as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of wear and corrosion resistant ceramics, and particularly relates to a seawater wear and corrosion resistant carbide sintered body as well as a preparation method and application thereof. The carbide sintered body provided by the invention comprises a multi-component transition metal carbide matrix and a small amount of other corrosion-resistant metal elements free in the multi-component transition metal carbide matrix, the multi-component transition metal carbide matrix is a high-entropy carbide composed of transition metal elements and a C element, and the transition metal elements comprise a Ti element, a V element, a Nb element, a Mo element and a W element; the other few corrosion-resistant metal elements comprise one or more of an Al element, an Ni element, a Cu element and a Cr element; and the mass of other few corrosion-resistant metal elements accounts for less than or equal to 8% of the total mass of the carbide sintering body. The carbide sintered body provided by the invention has high hardness and excellent seawater wear and corrosion resistance, and has a good application prospect under complex marine corrosion and wear working conditions.

Description

Technical Field

[0001] The invention belongs to the technical field of wear and corrosion resistant ceramics, and in particular relates to a carbide sintered body resistant to seawater wear and corrosion, and a preparation method and application thereof. Background Art

[0002] The ocean is an important area of ​​human activity and a rich resource base. It has the characteristics of high heat, high humidity and strong corrosion. It is one of the most demanding service environments for engineering components. For moving components serving in the marine environment, such as pistons, valves, and transmission shafts, they must also undergo mechanical friction and wear. Wear corrosion is not a simple superposition of friction, wear and corrosion. In the process of wear corrosion, the friction and wear generated by mechanical movement causes the surface of the material to be depassivated, causing the sintered material to directly contact the corrosive medium and aggravate the corrosion, which is called wear-aggravated corrosion; at the same time, pitting in the process will also destroy the organizational structure of the contact surface and reduce the friction and wear performance, which is called corrosion-promoted wear. Therefore, the interaction of wear and corrosion seriously threatens the safe serviceability of marine equipment.

[0003] At present, the materials used to resist seawater wear and corrosion are mostly titanium alloys, copper-nickel alloys and stainless steel. These metal materials can form a passivation film on the surface in the marine environment to effectively prevent seawater from corroding the metal substrate. However, the wear resistance of such materials is poor, and once the passivation film is damaged, the substrate material will be exposed to the seawater medium, accelerating the wear and corrosion rate of the components and greatly shortening the service life of the equipment. Summary of the invention

[0004] The purpose of the present invention is to provide a carbide sintered body resistant to seawater wear and corrosion, and a preparation method and application thereof. The carbide sintered body provided by the present invention has high hardness and excellent seawater wear and corrosion resistance, and has good application prospects under complex marine corrosion and wear conditions.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a carbide sintered body resistant to seawater wear and corrosion, comprising a multi-component transition metal carbide matrix and a small amount of other corrosion-resistant metal elements free in the multi-component transition metal carbide matrix;

[0007] The multi-component transition metal carbide matrix is ​​a high entropy carbide composed of transition metal elements and C elements, and the transition metal elements include Ti elements, V elements, Nb elements, Mo elements and W elements;

[0008] The other small amount of corrosion-resistant metal elements include one or more of Al, Ni, Cu and Cr; the other small amount of corrosion-resistant metal elements in the carbide sintered body are in the form of metal element and / or carbide;

[0009] The mass of the other small amount of corrosion-resistant metal elements accounts for 8wt% or less of the total mass of the carbide sintered body.

[0010] Preferably, in the multi-component transition metal carbide matrix: the mass of the Ti element accounts for 31 to 41.5wt% of the total mass of the transition metal elements, the mass of the V element accounts for 5 to 9wt% of the total mass of the transition metal elements, the mass of the Nb element accounts for 8 to 19wt% of the total mass of the transition metal elements, the mass of the Mo element accounts for 16 to 27.5wt% of the total mass of the transition metal elements, and the mass of the W element accounts for 15 to 29wt% of the total mass of the transition metal elements.

[0011] Preferably, the mass of the other small amount of corrosion-resistant metal elements accounts for 1 to 8 wt % of the total mass of the carbide sintered body;

[0012] The mass of the multi-component transition metal carbide matrix accounts for 90-99 wt % of the total mass of the carbide sintered body.

[0013] Preferably, the relative density of the carbide sintered body resistant to seawater wear and corrosion is ≥99%, and the grain size of the multi-component transition metal carbide matrix is ​​0.5-2 μm.

[0014] The present invention provides a method for preparing a carbide sintered body resistant to seawater wear and corrosion as described in the above technical solution, comprising the following steps:

[0015] The unit transition metal carbide powder is mixed with a small amount of other corrosion-resistant metal powder to obtain a mixed powder, wherein the unit transition metal carbide powder includes TiC powder, VC powder, Mo powder, 2 C powder, NbC powder and WC powder;

[0016] The mixed powder is sintered to obtain the carbide sintered body resistant to seawater wear and corrosion.

[0017] Preferably, the average particle size of the unit transition metal carbide powder is independently 0.7 to 3 μm;

[0018] The purity of the unit transition metal carbide powder is ≥ 99%;

[0019] The other small amount of corrosion-resistant metal powder includes one or more of Al powder, Ni powder, Cu powder and Cr powder;

[0020] The average particle size of the other small amount of corrosion-resistant metal powder is 0.5 to 1 μm;

[0021] The purity of the other small amount of corrosion-resistant metal single substance powder is ≥99%.

[0022] Preferably, the mixing comprises the following steps:

[0023] A unit transition metal carbide powder, a small amount of other corrosion-resistant metal powder, a grinding ball and a solvent are mixed and ball-milled to obtain a slurry; the grinding balls include a first-graded grinding ball and a second-graded grinding ball, the diameter of the first-graded grinding ball is 10-15 mm, the diameter of the second-graded grinding ball is 4-6 mm, the mass ratio of the first-graded grinding ball to the second-graded grinding ball is 1:1-2, the total mass of the unit transition metal carbide powder and the small amount of other corrosion-resistant metal powder to the mass of the grinding ball is 1:4-6, the solvent includes ethanol or water, the rotation speed of the ball mill is 100-300 rpm, and the time is 16-24 hours;

[0024] The slurry is dried and sieved in sequence to obtain the mixed powder, the drying is forced air drying, the drying temperature is 45-55° C., the drying time is 9-11 hours, and the sieving uses a 100-mesh or 325-mesh standard stainless steel test sieve.

[0025] Preferably, the sintering is spark plasma hot pressing sintering, the sintering temperature is 1750-2000° C., the holding time is 8-15 min, the loading pressure is 40-55 MPa, and the sintering is carried out in a vacuum environment or a protective gas atmosphere, and the protective gas is an inert gas.

[0026] The present invention provides the use of the carbide sintered body described in the above technical solution or the carbide sintered body prepared by the preparation method described in the above technical solution as a seawater wear and corrosion resistant material.

[0027] Preferably, the seawater wear and corrosion resistant material includes movable components serving in a marine environment.

[0028] The present invention provides a carbide sintered body resistant to seawater wear and corrosion, comprising a multi-component transition metal carbide matrix and other small amounts of corrosion-resistant metal elements free in the multi-component transition metal carbide matrix; the multi-component transition metal carbide matrix is ​​a high-entropy carbide composed of transition metal elements and C elements, the transition metal elements include Ti elements, V elements, Nb elements, Mo elements and W elements; the other small amounts of corrosion-resistant metal elements include one or more of Al elements, Ni elements, Cu elements and Cr elements; the other small amounts of corrosion-resistant metal elements are in the form of metal simple substances and / or carbides in the carbide sintered body; the mass of the other small amounts of corrosion-resistant metal elements accounts for ≤8wt% of the total mass of the carbide sintered body. The carbide sintered body provided by the present invention is a single-phase structure or a two-phase structure in which a small amount of corrosion-resistant metal elements are dispersed in the form of a second phase. The multi-component transition metal carbide matrix is ​​a high-entropy carbide formed by five transition metal elements. It has excellent wear resistance in the absence of a medium, and can form a TiO 2 、V 2 O 5 , Nb 2 O 5 、MoO 3 , WO 3 and Al 2 O 3 、NiO、Cu 2 O and Cr 2 O 3 One or more metal oxides with different functions, wherein TiO 2 , Nb 2 O 5 and Al 2 O 3 It can be used as an excellent passivation film to prevent further erosion of the substrate by seawater and improve the corrosion resistance of the material. 3 、V 2 O 5 and MoO 3 With a layered structure, the self-lubricating property of the material during mechanical friction is enhanced. NiO and Cu 2 O is conducive to the improvement of biofouling, Cr 2 O 3 and MoO 3 The carbide sintered body provided by the present invention has high hardness and excellent seawater wear and corrosion resistance, and has a good application prospect under complex marine corrosion and wear working conditions.

[0029] Furthermore, in the present invention, the relative density of the carbide sintered body resistant to seawater wear and corrosion is ≥99%, and the grain size of the multi-component transition metal carbide matrix is ​​0.5-2 μm. The carbide sintered body provided by the present invention has high relative density, fine grain size, and random grain orientation.

[0030] The present invention provides a method for preparing a sintered carbide body resistant to seawater wear and corrosion as described in the above technical solution, comprising the following steps: mixing a unit transition metal carbide powder with a small amount of other corrosion-resistant metal single substance powder to obtain a mixed powder, wherein the unit transition metal carbide powder comprises TiC powder, VC powder, Mo powder, 2 C powder, NbC powder and WC powder; sintering the mixed powder to obtain the carbide sintered body resistant to seawater wear and corrosion. The preparation method provided by the invention is simple and easy to implement and is suitable for industrial production.

[0031] Furthermore, in the present invention, the sintering is spark plasma hot pressing sintering, and the sintering temperature is 1750-2000° C. The present invention can obtain a carbide sintered body with high hardness and excellent seawater wear and corrosion resistance by controlling the sintering temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is the XRD spectrum of the seawater wear and corrosion resistant carbide sintered body prepared in Example 1;

[0033] Figure 2 The electron microscope image and energy spectrum of the seawater wear and corrosion resistant carbide sintered body prepared in Example 1;

[0034] Figure 3 The friction coefficient of the seawater wear and corrosion resistant carbide sintered body prepared in Example 1 in seawater medium;

[0035] Figure 4 Schematic diagram of wear and corrosion of the seawater wear and corrosion resistant carbide sintered body prepared in Example 1 in seawater medium;

[0036] Figure 5 This is the XRD spectrum of the seawater wear and corrosion resistant carbide sintered body prepared in Comparative Example 1. DETAILED DESCRIPTION

[0037] The present invention provides a carbide sintered body resistant to seawater wear and corrosion, comprising a multi-component transition metal carbide matrix and a small amount of other corrosion-resistant metal elements free in the multi-component transition metal carbide matrix;

[0038] The multi-component transition metal carbide matrix is ​​a high entropy carbide composed of transition metal elements and C elements, and the transition metal elements include Ti elements, V elements, Nb elements, Mo elements and W elements;

[0039] The other small amount of corrosion-resistant metal elements include one or more of Al, Ni, Cu and Cr; the other small amount of corrosion-resistant metal elements in the carbide sintered body are in the form of metal element and / or carbide;

[0040] The mass of the other small amount of corrosion-resistant metal elements accounts for 8wt% or less of the total mass of the carbide sintered body.

[0041] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0042] The carbide sintered body resistant to seawater wear and corrosion provided by the present invention is a two-phase structure in which a small amount of corrosion-resistant metal elements are dispersedly distributed in the form of a second phase. The matrix phase of the carbide sintered body provided by the present invention is a multi-component transition metal carbide, and the multi-component transition metal carbide matrix is ​​a high-entropy carbide formed by five transition metal element components.

[0043] The carbide sintered body resistant to seawater wear and corrosion provided by the present invention comprises a multi-component transition metal carbide matrix. In the present invention, the multi-component transition metal carbide matrix is ​​a high entropy carbide composed of transition metal elements and C elements, and the transition metal elements include Ti elements, V elements, Nb elements, Mo elements and W elements. In the multi-component transition metal carbide matrix: the mass of the Ti element accounts for a percentage of the total mass of the transition metal elements of preferably 31 to 41.5wt%, preferably 31 to 40.5wt%, and in the embodiment, it can be 33.74wt%, 31.45wt%, 37.74wt%, 39.13wt%, 40.24wt%. The mass of the V element accounts for a percentage of the total mass of the transition metal elements of preferably 5 to 9wt%, preferably 5.5 to 7.5wt%, and in the embodiment, it can be 5.98wt%, 6.7wt%, 6.95wt%, 7.43wt%, 6.07wt%. The mass percentage of Nb element to the total mass of the transition metal elements is preferably 8-19wt%, preferably 9-19wt%, and in the embodiments, it can be 17.75wt%, 17.42wt%, 19wt%, 9.02wt%, 10.43wt%. The mass percentage of Mo element to the total mass of the transition metal elements is preferably 16-27.5wt%, preferably 17-22.5wt%, and in the embodiments, it can be 18.76wt%, 22.08wt%, 17.17wt%, 27.19wt%, 17.13wt%. The mass percentage of W element to the total mass of the transition metal elements is preferably 15-29wt%, preferably 17-26.5wt%, and in the embodiments, it can be 23.77wt%, 22.35wt%, 19.14wt%, 17.23wt%, 26.13wt%.

[0044] The carbide sintered body resistant to seawater wear and corrosion provided by the present invention comprises other small amounts of corrosion-resistant metal elements free in the multi-component transition metal carbide matrix. In the present invention, the other small amounts of corrosion-resistant metal elements comprise one or more of Al, Ni, Cu and Cr; the other small amounts of corrosion-resistant metal elements in the carbide sintered body are in the form of metal elements and / or carbides;

[0045] In the present invention, the mass of the multi-component transition metal carbide matrix accounts for preferably 90 to 99 wt %, more preferably 95 to 99 wt %, of the total mass of the carbide sintered body.

[0046] In the present invention, the mass percentage of the other small amount of corrosion-resistant metal elements in the total mass of the carbide sintered body is ≤8wt%, preferably 1-8wt%.

[0047] In the present invention, the relative density of the carbide sintered body is preferably ≥99%, and the grain size of the carbide sintered body is preferably 0.5-2 μm.

[0048] The present invention provides a method for preparing a carbide sintered body resistant to seawater wear and corrosion as described in the above technical solution, comprising the following steps:

[0049] The unit transition metal carbide powder is mixed with a small amount of other corrosion-resistant metal powder to obtain a mixed powder, wherein the unit transition metal carbide powder includes TiC powder, VC powder, Mo powder, 2 C powder, NbC powder and WC powder;

[0050] The mixed powder is sintered to obtain the carbide sintered body resistant to seawater wear and corrosion.

[0051] The present invention mixes a unit transition metal carbide powder with a small amount of other corrosion-resistant metal powder to obtain a mixed powder, wherein the unit transition metal carbide powder includes TiC powder, VC powder, Mo powder, 2 C powder, NbC powder and WC powder. In the present invention, the average particle size of the TiC powder is preferably 0.7 to 3 μm. The purity of the TiC powder is preferably ≥ 99%. The average particle size of the VC powder is preferably 0.7 to 3 μm. The purity of the VC powder is preferably ≥ 99%. 2 The average particle size of the C powder is preferably 0.7 to 3 μm. 2 The purity of C powder is preferably ≥99%. The average particle size of the NbC powder is preferably 0.7-3 μm. The purity of the NbC powder is preferably ≥99%. The average particle size of the WC powder is preferably 0.7-3 μm. The purity of the WC powder is preferably ≥99%. The other small amount of corrosion-resistant metal powders include one or more of Al powder, Ni powder, Cu powder and Cr powder, and more preferably one, two, three or four of Al powder, Ni powder, Cu powder and Cr powder. The average particle size of the other small amount of corrosion-resistant metal powders is preferably 0.5-1 μm. The purity of the other small amount of corrosion-resistant metal powders is preferably ≥99%. The mass of the other small amount of corrosion-resistant metal powders accounts for 1-8% of the total mass of the unit transition metal carbide powder and other small amount of corrosion-resistant metal powders, and is specifically 1%, 5%, 3%, 8% or 7% in the embodiment. The mass of the unit transition metal carbide powder accounts for 92-99% of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder.

[0052] In the present invention, the mass of the TiC powder accounts for preferably 34.5-47.6% of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder, and is specifically 39.60%, 36.10%, 42.68%, 44.16% or 43.71% in the embodiments.

[0053] In the present invention, the mass of the VC powder accounts for preferably 6.4-8.95% of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder, and is specifically 6.93%, 7.60%, 7.76%, 8.28% or 6.51% in the embodiments.

[0054] In the present invention, the mass of the NbC powder accounts for preferably 9.2-19.5% of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder, and is specifically 18.81%, 18.05%, 19.40%, 9.20% or 10.23% in the embodiments.

[0055] In the present invention, the Mo 2 The mass of C powder accounts for 8.2-14.9% of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder, and is specifically 9.90%, 11.40%, 8.73%, 13.80% or 8.37% in the embodiments.

[0056] In the present invention, the mass of the WC powder accounts for preferably 16.5-25.8% of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder, and is specifically 23.76%, 21.85%, 18.43%, 16.56% or 24.18% in the embodiments.

[0057] As a specific embodiment of the present invention, the other small amount of corrosion-resistant metal powder is Al powder, and the mass of the Al powder accounts for 1% of the total mass of the unit transition metal carbide powder and the other small amount of corrosion-resistant metal powder.

[0058] As a specific embodiment of the present invention, the other small amount of corrosion-resistant metal powder is Cr powder, and the mass of the Cr powder accounts for 5% of the total mass of the unit transition metal carbide powder and the other small amount of corrosion-resistant metal powder.

[0059] As a specific embodiment of the present invention, the other small amount of corrosion-resistant metal powder is Ni powder and Cu powder, and the mass of the Ni powder accounts for 1.5% of the total mass of the unit transition metal carbide powder and the other small amount of corrosion-resistant metal powder. The mass of the Cu powder accounts for 1.5% of the total mass of the unit transition metal carbide powder and the other small amount of corrosion-resistant metal powder.

[0060] As a specific embodiment of the present invention, the other small amount of corrosion-resistant metal powder is Cr powder, Ni powder, Al powder and Cu powder, and the mass of the Cr powder accounts for 2% of the total mass of the unit transition metal carbide powder and other small amount of corrosion-resistant metal powder. The mass of the Ni powder accounts for 1% of the total mass of the unit transition metal carbide powder and other small amount of corrosion-resistant metal powder. The mass of the Al powder accounts for 3% of the total mass of the unit transition metal carbide powder and other small amount of corrosion-resistant metal powder. The mass of the Cu powder accounts for 2% of the total mass of the unit transition metal carbide powder and other small amount of corrosion-resistant metal powder.

[0061] As a specific embodiment of the present invention, the other small amount of corrosion-resistant metal powder is Cr powder and Ni powder, and the mass of the Cr powder accounts for 4% of the total mass of the unit transition metal carbide powder and the other small amount of corrosion-resistant metal powder. The mass of the Ni powder accounts for 3% of the total mass of the unit transition metal carbide powder and the other small amount of corrosion-resistant metal powder.

[0062] In the present invention, the mixing preferably comprises the following steps:

[0063] The unit transition metal carbide powder, other small amounts of corrosion-resistant metal powder, grinding balls and solvent are mixed and ball-milled to obtain a slurry. In the present invention, the grinding balls preferably include one or more of tungsten carbide balls, aluminum oxide balls, silicon nitride balls, zirconium oxide balls and cemented carbide grinding balls. The grinding balls preferably include first-graded grinding balls and second-graded grinding balls, the diameter of the first-graded grinding balls is preferably 10 to 15 mm, and can be 10 mm in the embodiment, the diameter of the second-graded grinding balls is preferably 4 to 6 mm, and can be 4 mm in the embodiment, and the mass ratio of the first-graded grinding balls to the second-graded grinding balls is preferably 1:1 to 2, and can be 1:1 or 1:2 in the embodiment. The ratio of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder to the mass of the grinding balls is 1:4 to 6, specifically 1:4 or 1:6. The solvent preferably includes ethanol or water, specifically anhydrous ethanol. The purity of the anhydrous ethanol is ≥99%. The mass of the solvent is preferably 40-45% of the total mass of the unit transition metal carbide powder and other small amounts of corrosion-resistant metal powder. In the present invention, the ball milling is preferably carried out in a planetary ball mill. The speed of the ball milling is preferably 100-300 rpm, and the time is preferably 16-24 hours.

[0064] The present invention sequentially dries and sieves the slurry to obtain the mixed powder. In the present invention, the drying is specifically blast drying, the drying temperature is preferably 45 to 55° C., and the drying time is preferably 9 to 11 hours. The sieving preferably uses a 100-mesh or 325-mesh standard stainless steel test sieve.

[0065] After obtaining the mixed powder, the present invention sintered the mixed powder to obtain the carbide sintered body. In the present invention, the sintering is preferably spark plasma hot pressing sintering, the sintering temperature is preferably 1750-2000°C, more preferably 1750-1850°C, specifically 1850°C, 1750°C, 1800°C or 1900°C in the embodiment, and the sintering holding time is preferably 8-15min, more preferably 9-13min. The loading pressure of the sintering is preferably 40-55MPa, more preferably 40-50MPa. The sintering is preferably carried out in a vacuum environment or a protective gas atmosphere, and the protective gas is preferably an inert gas.

[0066] The present invention provides the use of the carbide sintered body described in the above technical solution or the carbide sintered body prepared by the preparation method described in the above technical solution as a seawater wear and corrosion resistant material.

[0067] In the present invention, the seawater wear and corrosion resistant material preferably includes a movable component serving in a marine environment, specifically a piston, a valve or a transmission shaft.

[0068] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0069] Example 1

[0070] The raw materials used in this example include:

[0071] TiC powder (purity ≥ 99%, average particle size 1.8 μm): 39.60%;

[0072] VC powder (purity ≥ 99%, average particle size 1.5 μm): 6.93%;

[0073] NbC powder (purity ≥ 99%, average particle size 1.2 μm): 18.81%;

[0074] Mo 2 C powder (purity ≥ 99%, average particle size 1 μm): 9.90%;

[0075] WC powder (purity ≥ 99%, average particle size 0.9 μm): 23.76%;

[0076] Al powder (purity ≥ 99%, average particle size 0.9 μm): 1.00%;

[0077] The solvent is anhydrous ethanol, and the added mass is 40-45% of the total mass of the above powder.

[0078] Grinding ball: tungsten carbide grinding ball.

[0079] The above raw materials were ball-milled and mixed in a planetary ball mill, with a ball-to-material ratio of 6:1, a mass ratio of 10 mm diameter tungsten carbide grinding balls to 4 mm diameter tungsten carbide grinding balls of 1:2, a ball milling speed of 300 rpm, and a ball milling mixing time of 18 h. After pouring out, the mixture was spread evenly and dried in a blast drying oven at 55° C. for 10 h to obtain a mixed material.

[0080] Weigh 24.50g of the mixed material and pour it into a graphite mold. After dry pressing and preforming, put it into a spark plasma hot pressing sintering furnace, and heat it to 1050°C in a vacuum atmosphere, then introduce argon gas, and load the pressure to 40MPa. After stabilization, heat it again to 1850°C, keep it at 1850°C for 9 minutes, and then cool it to room temperature with the furnace to obtain a carbide sintered body. The carbide sintered body prepared in this embodiment consists of a multi-component transition metal carbide matrix and Al elements free in the multi-component transition metal carbide matrix. The form of Al element is metal element and / or carbide; the mass of Ti element accounts for 33.74wt% of the total mass of the transition metal elements, the mass of V element accounts for 5.98wt% of the total mass of the transition metal elements, the mass of Nb element accounts for 17.75wt% of the total mass of the transition metal elements, the mass of Mo element accounts for 18.76wt% of the total mass of the transition metal elements, and the mass of W element accounts for 23.77wt% of the total mass of the transition metal elements. The mass of Al element accounts for 1% of the total mass of the carbide sintered body. The relative density of the carbide sintered body prepared in this embodiment is ≥99% (99.5%), and the grain size of the carbide sintered body is 0.5 to 2μm.

[0081] Example 2

[0082] The raw materials used in this embodiment include:

[0083] TiC powder (purity ≥ 99%, average particle size 1 μm): 36.10%;

[0084] VC powder (purity ≥ 99%, average particle size 0.9 μm): 7.60%;

[0085] NbC powder (purity ≥ 99%, average particle size 1.1 μm): 18.05%;

[0086] Mo 2 C powder (purity ≥ 99%, average particle size 0.8 μm): 11.40%;

[0087] WC powder (purity ≥ 99%, average particle size 0.9 μm): 21.85%;

[0088] Cr powder (purity ≥ 99%, average particle size 0.7 μm): 5%.

[0089] The solvent is anhydrous ethanol, and the added mass is 40-45% of the total mass of the above powder.

[0090] Grinding ball: carbide grinding ball.

[0091] The raw materials were mixed by ball milling in a planetary ball mill, with a ball-to-material ratio of 4:1, wherein the mass ratio of grinding balls with a diameter of 10 mm to that with a diameter of 4 mm was 1:1, the ball milling speed was 200 rpm, the ball milling mixing time was 22 h, the mixture was poured out and spread evenly, and dried in a blast drying oven at 45°C for 12 h to obtain a mixed material;

[0092] Weigh 24.5g of the mixed material and pour it into a graphite mold, pressurize and put it into a plasma discharge sintering furnace, introduce argon, heat it to 1050°C in a vacuum atmosphere, then introduce argon, and load the pressure to 50MPa at the same time. After stabilization, heat it again to 1750°C, keep it at 1750°C for 13min, and then cool it to room temperature with the furnace to obtain a carbide sintered body. The carbide sintered body prepared in this embodiment consists of a multi-component transition metal carbide matrix and Cr elements free in the multi-component transition metal carbide matrix. The form of Cr element is metal element and / or carbide; the mass of Ti element accounts for 31.45wt% of the total mass of the transition metal elements, the mass of V element accounts for 6.70wt% of the total mass of the transition metal elements, the mass of Nb element accounts for 17.42wt% of the total mass of the transition metal elements, the mass of Mo element accounts for 22.08wt% of the total mass of the transition metal elements, and the mass of W element accounts for 22.35wt% of the total mass of the transition metal elements. The mass of Cr element accounts for 5% of the total mass of the carbide sintered body. The relative density of the carbide sintered body prepared in this embodiment is ≥99% (99.23%), and the grain size of the carbide sintered body is 0.5-2μm.

[0093] Example 3

[0094] The raw materials used in this example include:

[0095] TiC powder (purity ≥ 99%, average particle size 0.8 μm): 42.68%;

[0096] VC powder (purity ≥ 99%, average particle size 0.9 μm): 7.76%;

[0097] NbC powder (purity ≥ 99%, average particle size 0.7 μm): 19.40%;

[0098] Mo 2 C powder (purity ≥ 99%, average particle size 1 μm): 8.73%;

[0099] WC powder (purity ≥ 99%, average particle size 0.7 μm): 18.43%;

[0100] Ni powder (purity ≥ 99%, average particle size 0.6 μm): 1.50%;

[0101] Cu powder (purity ≥ 99%, average particle size 0.7 μm): 1.5%.

[0102] The solvent is anhydrous ethanol, and the added amount is 40-45% of the total mass of the above powder.

[0103] Grinding ball: Silicon nitride grinding ball.

[0104] The raw materials were mixed by ball milling in a planetary ball mill, with a ball-to-material ratio of 6:1, a mass ratio of grinding balls with a diameter of 10 mm to that with a diameter of 4 mm of 1:1, a ball milling speed of 250 rpm, and a ball milling mixing time of 20 h. After pouring out, the mixture was spread evenly and dried in a vacuum drying oven at 50° C. for 9 h to obtain a mixed material.

[0105] 24.5 g of the mixture was weighed and poured into a graphite mold. After dry pressing and preforming, it was placed in a spark plasma hot pressing sintering furnace and heated to 1000° C. in a vacuum atmosphere. Then, argon was introduced and loaded to 45 MPa. After stabilization, the temperature was raised to 1800° C. again. The mixture was kept at 1800° C. for 11 min and then cooled to room temperature with the furnace to obtain a carbide sintered body. The carbide sintered body prepared in this embodiment consists of a multi-component transition metal carbide matrix and Cu and Ni elements free in the multi-component transition metal carbide matrix. C The form of u and Ni elements is metal element and / or carbide; the mass percentage of Ti element to the total mass percentage of the transition metal elements is 37.74wt%, the mass percentage of V element to the total mass percentage of the transition metal elements is 6.95wt%, the mass percentage of Nb element to the total mass percentage of the transition metal elements is 19.00wt%, the mass percentage of Mo element to the total mass percentage of the transition metal elements is 17.17wt%, and the mass percentage of W element to the total mass percentage of the transition metal elements is 19.14wt%. The mass of Cu and Ni elements each accounts for 1.5% of the total mass of the carbide sintered body. The relative density of the carbide sintered body prepared in this embodiment is ≥99% (99.56%), and the grain size of the carbide sintered body is 0.5 to 2μm.

[0106] Example 4

[0107] The raw materials used in this embodiment include:

[0108] TiC powder (purity ≥ 99%, average particle size 1 μm): 44.16%;

[0109] VC powder (purity ≥ 99%, average particle size 0.9 μm): 8.28%;

[0110] NbC powder (purity ≥ 99%, average particle size 1.1 μm): 9.20%;

[0111] Mo 2 C powder (purity ≥ 99%, average particle size 0.8 μm): 13.80%;

[0112] WC powder (purity ≥ 99%, average particle size 0.9 μm): 16.56%;

[0113] Cr powder (purity ≥ 99%, average particle size 0.7 μm): 2%.

[0114] Ni powder (purity ≥ 99%, average particle size 0.7 μm): 1%.

[0115] Al powder (purity ≥ 99%, average particle size 0.7 μm): 3%.

[0116] Cu powder (purity ≥ 99%, average particle size 0.7 μm): 2%.

[0117] The solvent is anhydrous ethanol, and the added mass is 40-45% of the total mass of the above powder.

[0118] Grinding ball: carbide grinding ball.

[0119] The raw materials were mixed by ball milling in a planetary ball mill, with a ball-to-material ratio of 4:1, wherein the mass ratio of grinding balls with a diameter of 10 mm to that with a diameter of 4 mm was 1:2, the ball milling speed was 200 rpm, the ball milling mixing time was 24 h, the mixture was poured out and spread evenly, and dried in a blast drying oven at 48° C. for 11 h to obtain a mixed material;

[0120] Weigh 24.5g of the mixed material and pour it into a graphite mold, pressurize it and put it into a plasma discharge sintering furnace, introduce argon, heat it to 1200°C in a vacuum atmosphere, then introduce argon, and load the pressure to 43MPa. After stabilization, heat it to 1900°C again, keep it at 1900°C for 11 minutes, and then cool it to room temperature with the furnace to obtain a carbide sintered body. The carbide sintered body prepared in this embodiment consists of a multi-component transition metal carbide matrix and Cr, Ni, Al and Cu elements free in the multi-component transition metal carbide matrix. The form of Cr, Ni, Al and Cu elements is metal element and / or carbide; the mass percentage of Ti element to the total mass percentage of transition metal elements is 39.13wt%, the mass percentage of V element to the total mass percentage of transition metal elements is 7.43wt%, the mass percentage of Nb element to the total mass percentage of transition metal elements is 9.02wt%, the mass percentage of Mo element to the total mass percentage of transition metal elements is 27.19wt%, and the mass percentage of W element to the total mass percentage of transition metal elements is 17.23wt%. The mass percentage of Cr, Ni, Al and Cu elements is 2%, 1%, 3% and 2% of the total mass of the carbide sintered body, respectively. The relative density of the carbide sintered body prepared in this embodiment is ≥99% (99.56%), and the grain size of the carbide sintered body is 0.5-2μm.

[0121] Example 5

[0122] The raw materials used in this embodiment include:

[0123] TiC powder (purity ≥ 99%, average particle size 1 μm): 43.71%;

[0124] VC powder (purity ≥ 99%, average particle size 0.9 μm): 6.51%;

[0125] NbC powder (purity ≥ 99%, average particle size 1.1 μm): 10.23%;

[0126] Mo 2 C powder (purity ≥ 99%, average particle size 0.8 μm): 8.37%;

[0127] WC powder (purity ≥ 99%, average particle size 0.9 μm): 24.18%;

[0128] Cr powder (purity ≥ 99%, average particle size 0.7 μm): 4%.

[0129] Ni powder (purity ≥ 99%, average particle size 0.7 μm): 3%.

[0130] The solvent is anhydrous ethanol, and the added mass is 40-45% of the total mass of the above powder.

[0131] Grinding ball: carbide grinding ball.

[0132] The raw materials were ball-milled and mixed in a planetary ball mill, with a ball-to-material ratio of 6:1, wherein the mass ratio of grinding balls with a diameter of 10 mm to that with a diameter of 4 mm was 1:1, the ball milling speed was 300 rpm, the ball milling mixing time was 16 h, the mixture was poured out and spread evenly, and dried in a blast drying oven at 50° C. for 9 h to obtain a mixed material;

[0133] Weigh 24.5g of the mixed material and pour it into a graphite mold, pressurize it into a plasma discharge sintering furnace, introduce argon, heat it to 1050°C in a vacuum atmosphere, then introduce argon, and load the pressure to 50MPa at the same time. After stabilization, heat it again to 1850°C, keep it at 1850°C for 12min, and then cool it to room temperature with the furnace to obtain a carbide sintered body. The carbide sintered body prepared in this embodiment consists of a multi-component transition metal carbide matrix and Cr and Ni elements free in the multi-component transition metal carbide matrix. The Cr and Ni elements are in the form of metal elements and / or carbides; the mass of the Ti element accounts for 40.24wt% of the total mass of the transition metal elements, the mass of the V element accounts for 6.07wt% of the total mass of the transition metal elements, the mass of the Nb element accounts for 10.43wt% of the total mass of the transition metal elements, the mass of the Mo element accounts for 17.13wt% of the total mass of the transition metal elements, and the mass of the W element accounts for 26.13wt% of the total mass of the transition metal elements. The mass of the Cr and Ni elements accounts for 3% and 2% of the total mass of the carbide sintered body, respectively. The relative density of the carbide sintered body prepared in this embodiment is ≥99% (99.36%), and the grain size of the carbide sintered body is 0.5-2μm.

[0134] Comparative Example 1

[0135] The raw materials used in this comparative example include:

[0136] TiC powder (purity ≥ 99%, average particle size 1.8 μm): 39.60%;

[0137] VC powder (purity ≥ 99%, average particle size 1.5 μm): 6.93%;

[0138] NbC powder (purity ≥ 99%, average particle size 1.2 μm): 18.81%;

[0139] Mo 2 C powder (purity ≥ 99%, average particle size 1 μm): 9.90%;

[0140] WC powder (purity ≥ 99%, average particle size 0.9 μm): 23.76%;

[0141] Al powder (purity ≥ 99%, average particle size 0.9 μm): 1.00%;

[0142] The solvent is anhydrous ethanol, and the added mass is 40-45% of the total mass of the above powder.

[0143] Grinding ball: tungsten carbide grinding ball.

[0144] The raw materials were mixed by ball milling in a planetary ball mill, with a ball-to-material ratio of 6:1, a mass ratio of 10 mm diameter tungsten carbide grinding balls to 4 mm diameter tungsten carbide grinding balls of 1:2, a ball milling speed of 300 rpm, and a ball milling mixing time of 16 h. After pouring out, the mixture was spread evenly and dried in a blast drying oven at 55°C for 9 h to obtain a mixed material.

[0145] Weigh 24.5g of the mixed material and pour it into a graphite mold. After dry pressing and preforming, put it into a spark plasma hot pressing sintering furnace, and heat it to 1000℃ in a vacuum atmosphere. Then, introduce argon gas and load it to 40MPa. After stabilization, heat it to 1700℃ again, keep it at 1700℃ for 10min, and then cool it to room temperature with the furnace to obtain a carbide sintered body.

[0146] Comparative Example 2

[0147] The raw materials used in this comparative example include:

[0148] TiC powder (purity ≥ 99%, average particle size 1 μm): 48%;

[0149] VC powder (purity ≥ 99%, average particle size 1.5 μm): 0%;

[0150] NbC powder (purity ≥ 99%, average particle size 1.1 μm): 24.40%;

[0151] Mo 2 C powder (purity ≥ 99%, average particle size 1 μm): 0%;

[0152] WC powder (purity ≥ 99%, average particle size 0.9 μm): 25.60%;

[0153] Cr powder (purity ≥ 99%, average particle size 0.7 μm): 2%.

[0154] The solvent is anhydrous ethanol, and the added amount is 40-45% of the total mass of the above powder.

[0155] Grinding ball: Silicon nitride grinding ball.

[0156] The raw materials were mixed by ball milling in a planetary ball mill, with a ball-to-material ratio of 6:1, a mass ratio of grinding balls with a diameter of 10 mm to that with a diameter of 4 mm of 1:1, a ball milling speed of 250 rpm, and a ball milling mixing time of 18 h. After pouring out, the mixture was spread evenly and dried in a blast drying oven at 45°C for 11 h to obtain a mixed material.

[0157] Weigh 24.5g of the mixed material and pour it into a graphite mold. After dry pressing and preforming, put it into a spark plasma hot pressing sintering furnace, heat it to 1200℃ in a vacuum atmosphere, then introduce argon gas and load the pressure to 45MPa. After stabilization, heat it to 1800℃ again, keep it at 1800℃ for 11min, and then cool it to room temperature with the furnace to obtain a carbide sintered body.

[0158] Comparative Example 3

[0159] The raw materials used in this comparative example include:

[0160] TiC powder (purity ≥ 99%, average particle size 1 μm): 10.18%;

[0161] VC powder (purity ≥ 99%, average particle size 0.9 μm): 25.68%;

[0162] NbC powder (purity ≥ 99%, average particle size 0.7 μm): 27.64%;

[0163] Mo 2 C powder (purity ≥ 99%, average particle size 1 μm): 26.66%;

[0164] WC powder (purity ≥ 99%, average particle size 0.7 μm): 7.84%;

[0165] Ni powder (purity ≥ 99%, average particle size 0.6 μm): 2%;

[0166] The solvent is anhydrous ethanol, and the added amount is 40-45% of the total mass of the above powder.

[0167] Grinding ball: Silicon nitride grinding ball.

[0168] The raw materials were mixed by ball milling in a planetary ball mill, with a ball-to-material ratio of 6:1, a mass ratio of grinding balls with a diameter of 10 mm to that with a diameter of 4 mm of 1:1, a ball milling speed of 250 rpm, and a ball milling mixing time of 18 h. After pouring out, the mixture was spread evenly and dried in a blast drying oven at 45°C for 11 h to obtain a mixed material.

[0169] Weigh 24.5g of the mixed material and pour it into a graphite mold. After dry pressing and preforming, put it into a spark plasma hot pressing sintering furnace, heat it to 1250℃ in a vacuum atmosphere, then introduce argon gas and load the pressure to 50MPa. After stabilization, heat it to 1850℃ again, keep it at 1750℃ for 13min, and then cool it to room temperature with the furnace to obtain a carbide sintered body.

[0170] The seawater wear and corrosion resistant carbide sintered body prepared in Example 1 was subjected to XRD detection to obtain an XRD spectrum, as shown in FIG. Figure 1 It can be seen that the seawater wear and corrosion resistant carbide sintered body prepared in Example 1 is a typical FCC single-phase structure - high entropy phase, but the content of seawater corrosion resistant element (Al) is too low and cannot be detected by XRD.

[0171] The surface of the seawater wear and corrosion resistant carbide sintered body prepared in Example 1 was observed using a scanning electron microscope to obtain a SEM image, and an energy spectrum analysis was performed at the same time. Figure 2 As shown. Combined Figure 1 and Figure 2 The results show that the carbide sintered body prepared in Example 1 is a single-phase structure in which the constituent elements are evenly distributed, and pores are hardly observed on the surface.

[0172] The carbide sintered body prepared in Example 1 was tested in seawater medium using a friction and wear tester. Figure 3 As shown, the average friction coefficient is about 0.10, which is relatively small.

[0173] The XRD and SEM results of the carbide sintered bodies prepared in Examples 2 to 3 are similar to those in Example 1 and are not given here again.

[0174] The seawater wear and corrosion resistant carbide sintered body prepared in Comparative Example 1 was subjected to XRD detection to obtain an XRD spectrum, as shown in FIG. Figure 5 As shown. It can be seen that the sintered body with the same raw material ratio as Example 1 failed to form a high entropy phase under 1700°C, indicating that the formation temperature of the high entropy phase exceeds 1700°C. Comparative Example 2 is similar to Comparative Example 1. The reason why Comparative Example 2 failed to form a high entropy carbide is that there are only three types of carbides in its raw material composition, so even at a suitable temperature, it is impossible to form a high entropy carbide (in other words, the small number of elements leads to low configuration entropy and failure to form a high entropy carbide).

[0175] The density of the ceramic materials prepared in Examples 1 to 5 and Comparative Examples 1 to 3 was tested according to the Archimedean drainage method, and the results are listed in Table 1.

[0176] The wear rates of the products prepared in Examples 1 to 5 and Comparative Examples 1 to 3 were calculated according to the wear rate calculation formula W=V / (F·L), and the results are listed in Table 1. Wherein W represents the wear rate, F represents the load, V represents the wear volume, and L represents the sliding distance.

[0177] Table 1 Comparison of properties of carbide sintered bodies prepared in Examples 1 to 5 and Comparative Examples 1 to 3

[0178] Example / Comparative Example Density(%) Hardness(GPa) <![CDATA[Wear rate (mm 3 (N·m))]]> Example 1 99.12 26.92 <![CDATA[1.02·10 -7 ]]> Example 2 99.24 25.66 <![CDATA[1.53·10 -7 ]]> Example 3 99.53 25.89 <![CDATA[1.38·10 -7 ]]> Example 4 98.85 24.59 <![CDATA[1.38·10 -7 ]]> Example 5 99.32 28.78 <![CDATA[8.83·10 -8 ]]> Comparative Example 1 89.78 16.18 <![CDATA[7.58·10 -4 ]]> Comparative Example 2 98.89 21.27 <![CDATA[8.74·10 -5 ]]> Comparative Example 3 99.37 17.97 <![CDATA[5.67·10 -5 ]]>

[0179] It can be seen from the results in Table 1 that, relative to Comparative Example 1, the carbide sintered bodies prepared in the examples all achieve densification sintering and meet the engineering requirements of high hardness and high wear resistance. Comparative Example 2 shows that the material hardness is low and the wear rate is high, because the high-entropy phase with excellent performance cannot be formed using three unit transition metal carbides as raw materials. Comparative Example 3 shows that by reducing the content of Ti and W elements in the sintered body, the material hardness decreases significantly, and the material wear and corrosion resistance is poor.

[0180] It can be seen from the above embodiments that the carbide sintered body provided by the present invention has high hardness and excellent resistance to seawater wear and corrosion by controlling the type of transition metal elements and the sintering temperature during the preparation process, and has good application prospects under complex marine corrosion and wear conditions.

[0181] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A carbide sintered body resistant to seawater wear and corrosion, characterized in that: It comprises a multi-component transition metal carbide matrix and other small amounts of corrosion-resistant metal elements free in the multi-component transition metal carbide matrix; The multi-component transition metal carbide matrix is ​​a high entropy carbide composed of transition metal elements and C elements, and the transition metal elements include Ti elements, V elements, Nb elements, Mo elements and W elements; The other small amount of corrosion-resistant metal elements include one or more of Al, Ni, Cu and Cr; the other small amount of corrosion-resistant metal elements in the carbide sintered body are in the form of metal element and / or carbide; The mass of the other small amount of corrosion-resistant metal elements accounts for 8wt% or less of the total mass of the carbide sintered body.

2. The seawater wear and corrosion resistant carbide sintered body according to claim 1, characterized in that: In the multi-component transition metal carbide matrix: the mass of the Ti element accounts for 31-41.5wt% of the total mass of the transition metal elements, the mass of the V element accounts for 5-9wt% of the total mass of the transition metal elements, the mass of the Nb element accounts for 8-19wt% of the total mass of the transition metal elements, the mass of the Mo element accounts for 16-27.5wt% of the total mass of the transition metal elements, and the mass of the W element accounts for 15-29wt% of the total mass of the transition metal elements.

3. The seawater wear and corrosion resistant carbide sintered body according to claim 1 or 2, characterized in that: The mass of the other small amount of corrosion-resistant metal elements accounts for 1 to 8 wt% of the total mass of the carbide sintered body; The mass of the multi-component transition metal carbide matrix accounts for 90-99 wt % of the total mass of the carbide sintered body.

4. The seawater wear and corrosion resistant carbide sintered body according to claim 1, characterized in that: The relative density of the carbide sintered body resistant to seawater wear and corrosion is ≥99%, and the grain size of the multi-component transition metal carbide matrix is ​​0.5-2 μm.

5. The method for preparing a carbide sintered body resistant to seawater wear and corrosion according to any one of claims 1 to 4, characterized in that: The following steps are involved: Mixing a unit transition metal carbide powder with a small amount of other corrosion-resistant metal powder to obtain a mixed powder, wherein the unit transition metal carbide powder includes TiC powder, VC powder, Mo2C powder, NbC powder and WC powder; The mixed powder is sintered to obtain the carbide sintered body resistant to seawater wear and corrosion.

6. The preparation method according to claim 5, characterized in that: The average particle size of the unit transition metal carbide powder is independently 0.7 to 3 μm; The purity of the unit transition metal carbide powder is ≥ 99%; The other small amount of corrosion-resistant metal powder includes one or more of Al powder, Ni powder, Cu powder and Cr powder; The average particle size of the other small amount of corrosion-resistant metal powder is 0.5 to 1 μm; The purity of the other small amount of corrosion-resistant metal single substance powder is ≥99%.

7. The preparation method according to claim 5, characterized in that: The mixing comprises the following steps: A unit transition metal carbide powder, a small amount of other corrosion-resistant metal powder, a grinding ball and a solvent are mixed and ball-milled to obtain a slurry; the grinding balls include a first-graded grinding ball and a second-graded grinding ball, the diameter of the first-graded grinding ball is 10-15 mm, the diameter of the second-graded grinding ball is 4-6 mm, the mass ratio of the first-graded grinding ball to the second-graded grinding ball is 1:1-2, the total mass of the unit transition metal carbide powder and the small amount of other corrosion-resistant metal powder to the mass of the grinding ball is 1:4-6, the solvent includes ethanol or water, the rotation speed of the ball mill is 100-300 rpm, and the time is 16-24 hours; The slurry is dried and sieved in sequence to obtain the mixed powder, the drying is forced air drying, the drying temperature is 45-55° C., the drying time is 9-11 hours, and the sieving uses a 100-mesh or 325-mesh standard stainless steel test sieve.

8. The preparation method according to claim 5, characterized in that: The sintering is spark plasma hot pressing sintering, the sintering temperature is 1750-2000° C., the holding time is 8-15 minutes, the loading pressure is 40-55 MPa, and the sintering is carried out in a vacuum environment or a protective gas atmosphere, and the protective gas is an inert gas.

9. Use of the carbide sintered body according to any one of claims 1 to 4 or the carbide sintered body prepared by the preparation method according to any one of claims 5 to 8 as a seawater wear and corrosion resistant material.

10. The use according to claim 9, characterized in that: The seawater wear and corrosion resistant material includes movable components serving in a marine environment.

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