A method for producing a ceramic alloy powder

Abstract

The application relates to a preparation method of ceramic alloy powder. The ceramic alloy powder is prepared by the following steps: mixing CoCrFeMnZr high-entropy alloy powder and surface-plated ceramic powder in a mass ratio of 4:1 to 6:1, adding the mixture into a ball mill tank to form a slurry, wet ball milling, drying, and sieving. The ceramic alloy powder has good interface combination and can meet the requirements of high strength, high melting point and high wear resistance.

Description

Technical Field

[0001] This invention relates to the field of powder metallurgy, and more specifically, to a method for preparing ceramic alloy powder. Background Technology

[0002] With the continuous advancement of engineering equipment, materials possessing high strength, high wear resistance, and corrosion resistance are widely used, and the performance requirements for hardness, toughness, oxidation resistance, wear resistance, and corrosion resistance are becoming increasingly stringent. For example, in the field of cemented carbide, different binders have varying effects on the microstructure and properties of WC cemented carbide, necessitating the ability to adjust the elemental composition according to desired properties (e.g., hardness, toughness, oxidation resistance, wear resistance, and corrosion resistance). In the field of laser coating, coating materials are becoming increasingly diversified. Ceramic and high-entropy alloys have attracted widespread attention due to their high hardness and high-temperature resistance, becoming new research hotspots in laser cladding coating materials. In the field of cermet composites, due to the excellent properties of high-entropy alloys, many innovations revolve around using high-entropy alloys as the metallic alloy phase to replace traditional metallic alloy phases, thereby further improving the strength and toughness of cermet composites and reducing production costs.

[0003] CN117900499A discloses a method for preparing refractory high-entropy alloy composite powder for additive manufacturing, using W, Ta, Mo, Nb, and V nanoparticles and nano-ceramic particles with a purity greater than 99.9% as raw materials. The average particle size of W nanoparticles is D1 < D2 < D3 < D4 < D5. Although this method can solve the problems of easy component segregation and uneven particle size distribution of refractory high-entropy alloy powder, it requires the simultaneous preparation of multiple powders of different sizes, which places high demands on production. Furthermore, it pays less attention to the wettability and interfacial bonding between the refractory metal powder and the ceramic reinforcing phase.

[0004] CN118621171A discloses a method for preparing coreless high-entropy cermets. A mixture of Ni, Co, Fe, Cr, and Ti is prepared using high-energy ball milling. High-energy ball milling primarily involves the mechanical mixing of different elemental raw materials. Compared to atomization powdering after melting multi-component alloys, this method may not be conducive to the formation of solid solutions of the relevant metal elements.

[0005] CN118147474A discloses a method for preparing a high-strength and high-toughness aluminum-based composite material. The method involves ball milling vacuum-atomized high-entropy alloy powder (FeCoNiCrMn-based high-entropy alloy) with ceramic particles. The mass ratio of ceramic particles to high-entropy alloy powder is 10 to 20:100, resulting in a uniform composite powder. The high-entropy alloy powder has a size of 15 to 105 μm, and the ceramic particles have a size of 0.5 to 2 μm. The ball milling speed is 400 to 600 rpm, and the milling time is 12 hours. However, this method does not focus on whether there is a good interfacial bond between the high-entropy alloy powder and the ceramic particles, and the size of the high-entropy alloy powder is significantly larger than that of the ceramic particles.

[0006] While the above improvements describe various mixtures of high-entropy alloy powders and ceramic particles, they also have shortcomings: ① The different particle sizes of the metal raw materials impose many limitations on production; ② The mixing of high-entropy alloy powders and ceramic particles is not fully considered, including both the physical / chemical bonding between high-entropy alloy elements and the interfacial bonding between high-entropy alloy powders and ceramic particles, which leads to cracks in composite materials and laser coatings.

[0007] Therefore, it is necessary to simplify raw material restrictions and promote interfacial bonding between high-entropy alloying elements and between high-entropy alloy powder and ceramic particles in order to improve the hardness and strength of ceramic alloy powder in specific application scenarios. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a ceramic alloy powder with good interfacial bonding and capable of meeting the requirements of high strength, high melting point and high wear resistance.

[0009] The technical solution of this invention is:

[0010] A method for preparing ceramic alloy powder:

[0011] Step 1: High-entropy alloy powder is prepared by atomization. The high-entropy alloy powder is composed of Co, Cr, Fe, Mn and Zr, and the molar ratio of the corresponding elements is 0.5 to 0.8:1:1:1:1.

[0012] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​one or more of TiC, B4C, and ZrC, and the particle size of the ceramic powder matrix ranges from 20 to 80 micrometers.

[0013] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 in a mass ratio of 4:1 to 6:1 respectively; mix the two powders and add them to a ball mill jar to form a slurry, wet ball mill, dry, and sieve to obtain ceramic alloy powder.

[0014] Furthermore, the high-entropy alloy powder in step 1 is composed of Co, Cr, Fe, Mn, and Zr, with a corresponding element molar ratio of 0.5 to 0.8:1:1:1:1, and a particle size of 20 to 50 micrometers, or 20 to 30 micrometers or 40 to 50 micrometers.

[0015] Furthermore, the high-entropy alloy powder in step 1 is composed of Co, Cr, Fe, Mn, and Zr, with a corresponding element molar ratio of 0.6:1:1:1:1, and a particle size of 30 to 40 micrometers.

[0016] Furthermore, in step 2, the particle size range of the ceramic powder matrix is ​​40 to 50 micrometers, or 20 to 30 micrometers, or 70 to 80 micrometers.

[0017] Furthermore, the process for preparing high-entropy alloy powder by atomization in step 1 is as follows:

[0018] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted 3 to 5 times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 3 × 10⁻⁶. -4 Up to 5×10 - 4 The melting power is 30 to 50 kW, the atomization pressure is 5 to 15 MPa, the liquid flow rate is 10 kg / min to 20 kg / min, the atomization nozzle diameter is 5 mm to 10 mm, and after atomization, the powder is completely cooled and then sieved in an inert gas protective atmosphere to obtain high entropy alloy powder with a particle size of 20 to 50 micrometers.

[0019] Furthermore, the process for preparing high-entropy alloy powder by atomization in step 1 is as follows:

[0020] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted three times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 4 × 10⁻⁶. -4 The melting power was 40kW, the atomization pressure was 10MPa, the liquid flow rate was 15kg / min, the atomization nozzle diameter was 5mm, and after atomization, the powder was allowed to cool completely and then sieved in an inert gas protective atmosphere to obtain high-entropy alloy powder with a particle size of 30 to 40 micrometers.

[0021] Furthermore, in step 2, the ceramic powder coated on the surface is nickel-plated ceramic powder, and the nickel plating process is as follows:

[0022] (i) Sensitization and activation: Add ceramic powder at a rate of 20 to 30 g / L to a sensitization and activation solution at 20 to 30 °C, stir at a speed of 40 to 60 r / min for 6 to 10 min, wash with water, filter, and obtain sensitized and activated ceramic powder.

[0023] (ii) Electroless nickel plating: Sensitized and activated ceramic powder is added to the electroless nickel plating solution at a rate of 5 to 10 g / L, ultrasonically vibrated for 30 to 50 min, cleaned, and dried to obtain nickel-plated ceramic powder; the plating solution temperature is maintained at 30 to 50 °C, the pH value of the plating solution is 8 to 10, and the concentration of NiCl2 in the electroless nickel plating solution is 0.3 to 0.4 mol / L and NiSO4 is 0.1 to 0.2 mol / L.

[0024] Furthermore, in step 2, the ceramic powder coated on the surface is nickel-plated ceramic powder, and the nickel plating process is as follows:

[0025] (i) Sensitization and activation: The ceramic powder was added to the sensitization and activation solution at 30°C at a rate of 20 g / L, stirred at 40 r / min for 10 min, washed with water, filtered, and the sensitized and activated ceramic powder was obtained.

[0026] (ii) Electroless nickel plating: Sensitized and activated ceramic powder is added to the electroless nickel plating solution at a rate of 5 g / L, ultrasonically vibrated for 50 min, cleaned, and dried to obtain nickel-plated ceramic powder; the plating solution temperature is maintained at 50℃, the pH value of the plating solution is 9, and the concentration of NiCl2 in the electroless nickel plating solution is 0.35 mol / L and the concentration of NiSO4 is 0.15 mol / L.

[0027] Further, in step 3, the two powders are mixed and added to a ball mill jar to form a slurry. The mixture is then wet-milled using anhydrous ethanol or acetone as the grinding medium, with the amount added being 1.5 to 2 times the weight of the two powder mixture. The ball milling speed is 50 to 60 r / min, the ball milling time is 6 to 12 h, and the ball-to-powder ratio is 4:1 to 6:1. The mixture is then dried, sieved, and ceramic alloy powder is obtained.

[0028] Further, in step 3, the two powders are mixed and added to a ball mill jar to form a slurry. The mixture is then wet-milled using anhydrous ethanol as the grinding medium, with the amount added being twice the weight of the two powder mixture. The ball milling speed is 50 r / min, the milling time is 8 h, the ball-to-powder ratio is 5:1, and the mixture is dried and sieved to obtain ceramic alloy powder.

[0029] The high-entropy alloy powder is composed of Co, Cr, Fe, Mn, and Zr, with a corresponding elemental molar ratio of 0.5 to 0.8:1:1:1:1; the selection and content of the relevant elements are mainly based on the following considerations:

[0030] The addition of Co can improve the hardness and wear resistance of ceramic alloy powder products. It can also act as a binder and toughening phase. With increasing Co content, the hardness of the ceramic alloy powder products initially increases and then decreases. To save costs and reduce Co content, this scheme controls the Co molar ratio to be between 0.5 and 0.8, corresponding to a molar ratio of 1 for Cr, Fe, Mn, and Zr.

[0031] In high-entropy alloys, chromium (Cr) can improve hardness and wear resistance, forming FCC or BCC phases; it can also improve the high-temperature thermal stability, high-temperature oxidation resistance, hardness, and high-temperature strength of ceramic alloy powder products. Fe (Fe) in high-entropy alloys can also improve hardness and wear resistance, forming FCC or BCC phases; Fe has a similar effect to Co. Mn (Mn) in high-entropy alloys can improve high-temperature resistance and corrosion resistance; Zr, being a high-melting-point metal element, is generally not used in high-entropy alloys. In this scheme, to adapt to applications requiring high wear resistance, impact resistance, and high-temperature resistance, a certain amount of Zr is specifically added. Zr is an element that forms a face-centered cubic structure, increasing the elemental disorder in the ceramic alloy powder product and promoting the precipitation of the body-centered cubic B2 phase. The final ceramic alloy powder product contains both an FCC phase as the main component and a small amount of B2 phase.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] 1. Electroless nickel plating of ceramic powder enhances its wettability with high-entropy alloys and improves the interfacial metallurgical bonding between the two, overcoming the generation of micro-cracks during subsequent preparation of composite materials / laser cladding layers; thereby maximizing the synergistic effect between ceramic powder and high-entropy alloy powder, and comprehensively improving the overall performance of subsequent products, including strength, hardness, and wear resistance.

[0034] 2. When mixing high-entropy alloy powder and surface-coated ceramic powder, wet ball milling should be used. Avoid using high-energy ball milling and avoid ball milling at high speeds for extended periods to prevent damage to the surface coating of the ceramic powder.

[0035] 3. By adjusting the composition, this invention significantly reduces the content of Co element in the usual proportions of high-entropy alloys, thereby reducing costs. In addition, compared with common high-entropy alloy systems, it adopts a Co, Cr, Fe, Mn, Zr alloy system, aiming to obtain relatively high melting point, high wear resistance, and low cost.

[0036] 4. The high-entropy alloy powder in this invention is prepared by mixing, melting, and atomizing metal powders in a certain proportion. Compared to simply mixing metal powders in a certain proportion without going through the melting and atomization steps, atomizing powders after melting results in a more uniform distribution of elements than mechanically mixing powders, fundamentally avoiding component segregation and making the structure more uniform and the properties more consistent. Attached Figure Description

[0037] Figure 1 This is a morphology diagram of the high-entropy alloy spherical powder used in the embodiments of the present invention.

[0038] Figure 2 This is a morphology diagram of the surface-coated ceramic powder used in the embodiments of the present invention. Detailed Implementation

[0039] The present invention will be further described below with reference to specific embodiments.

[0040] Example 1

[0041] A method for preparing ceramic alloy powder:

[0042] Step 1: High-entropy alloy powder is prepared by atomization. The high-entropy alloy powder is composed of Co, Cr, Fe, Mn and Zr, and the molar ratio of the corresponding elements is 0.5:1:1:1:1.

[0043] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted three times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 3 × 10⁻⁶. -4 The melting power was 50kW, the atomization pressure was 15MPa, the liquid flow rate was 10kg / min, the atomization nozzle diameter was 5mm, and after atomization, the powder was allowed to cool completely and then sieved in an inert gas protective atmosphere to obtain high-entropy alloy powder with a particle size of 20 to 30 micrometers.

[0044] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​TiC with a particle size range of 20 to 30 micrometers and a coating thickness of 20 micrometers.

[0045] The surface-coated ceramic powder is a nickel-plated ceramic powder. The nickel plating process is as follows:

[0046] (i) Sensitization and activation: Add ceramic powder at a rate of 20 g / L to a sensitization and activation solution at 20 °C, stir at a speed of 40 r / min for 10 min, wash with water, filter, and obtain sensitized and activated ceramic powder.

[0047] (ii) Electroless nickel plating: Sensitized and activated ceramic powder is added to the electroless nickel plating solution at a concentration of 10 g / L, ultrasonically vibrated for 30 min, cleaned, and dried to obtain nickel-plated ceramic powder; the plating solution temperature is maintained at 30℃, the pH value of the plating solution is 8, and the concentration of NiCl2 in the electroless nickel plating solution is 0.4 mol / L and the concentration of NiSO4 is 0.2 mol / L.

[0048] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 4:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, the amount of which is 1.5 times the weight of the mixture of the two powders; the ball milling speed is 50 r / min, the ball milling time is 6 h, the ball-to-powder ratio is 4:1, dry, and sieve to obtain ceramic alloy powder.

[0049] Example 2

[0050] A method for preparing ceramic alloy powder:

[0051] Step 1: High-entropy alloy powder is prepared by atomization. The high-entropy alloy powder is composed of Co, Cr, Fe, Mn and Zr, and the molar ratio of the corresponding elements is 0.8:1:1:1:1.

[0052] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted five times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 5 × 10⁻⁶. -4 The melting power was 50kW, the atomization pressure was 5MPa, the liquid flow rate was 15kg / min, the atomization nozzle diameter was 10mm, and after atomization, the powder was allowed to cool completely and then sieved in an inert gas protective atmosphere to obtain high-entropy alloy powder with a particle size of 40 to 50 micrometers.

[0053] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​B4C with a particle size range of 70 to 80 micrometers and a coating thickness of 30 micrometers.

[0054] The surface-coated ceramic powder is a nickel-plated ceramic powder. The nickel plating process is as follows:

[0055] (i) Sensitization and activation: Add ceramic powder at a rate of 30 g / L to a sensitization and activation solution at 30 °C, stir at a speed of 60 r / min for 6 min, wash with water, filter, and obtain sensitized and activated ceramic powder.

[0056] (ii) Electroless nickel plating: Sensitized and activated ceramic powder is added to the electroless nickel plating solution at a rate of 5 g / L, ultrasonically vibrated for 50 min, cleaned, and dried to obtain nickel-plated ceramic powder; the plating solution temperature is maintained at 50℃, the pH value of the plating solution is 10, and the concentration of NiCl2 in the electroless nickel plating solution is 0.3 mol / L and the concentration of NiSO4 is 0.1 mol / L.

[0057] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 6:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, and add the ethanol or acetone at a mass ratio of 2 times the weight of the mixture of the two powders; the ball milling speed is 60 r / min, the ball milling time is 6 h, the ball-to-powder ratio is 6:1, dry, and sieve to obtain ceramic alloy powder.

[0058] Example 3

[0059] A method for preparing ceramic alloy powder:

[0060] Step 1: High-entropy alloy powder is prepared by atomization. The high-entropy alloy powder is composed of Co, Cr, Fe, Mn and Zr, and the molar ratio of the corresponding elements is 0.6:1:1:1:1.

[0061] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted three times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 4 × 10⁻⁶. -4 The melting power was 40kW, the atomization pressure was 10MPa, the liquid flow rate was 15kg / min, the atomization nozzle diameter was 5mm, and after atomization, the powder was allowed to cool completely and then sieved in an inert gas protective atmosphere to obtain high-entropy alloy powder with a particle size of 30 to 40 micrometers.

[0062] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​one or more of TiC, the particle size of the ceramic powder matrix ranges from 20 to 30 micrometers, and the coating thickness is 30 micrometers.

[0063] The surface-coated ceramic powder is a nickel-plated ceramic powder. The nickel plating process is as follows:

[0064] (i) Sensitization and activation: The ceramic powder was added to the sensitization and activation solution at 30°C at a rate of 20 g / L, stirred at 40 r / min for 10 min, washed with water, filtered, and the sensitized and activated ceramic powder was obtained.

[0065] (ii) Electroless nickel plating: Sensitized and activated ceramic powder is added to the electroless nickel plating solution at a rate of 5 g / L, ultrasonically vibrated for 50 min, cleaned, and dried to obtain nickel-plated ceramic powder; the plating solution temperature is maintained at 50℃, the pH value of the plating solution is 9, and the concentration of NiCl2 in the electroless nickel plating solution is 0.35 mol / L and the concentration of NiSO4 is 0.15 mol / L.

[0066] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 5:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, and add the ethanol or acetone at a mass ratio of twice the weight of the mixture of the two powders; the ball milling speed is 50 r / min, the ball milling time is 8 h, the ball-to-powder ratio is 5:1, dry, and sieve to obtain ceramic alloy powder.

[0067] Example 4

[0068] A method for preparing ceramic alloy powder:

[0069] Step 1: High-entropy alloy powder is prepared by atomization. The high-entropy alloy powder is composed of Co, Cr, Fe, Mn and Zr, and the molar ratio of the corresponding elements is 0.5:1:1:1:1.

[0070] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted three times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 3 × 10⁻⁶. -4 The melting power was 30kW, the atomization pressure was 10MPa, the liquid flow rate was 20kg / min, the atomization nozzle diameter was 5mm, and after atomization, the powder was allowed to cool completely and then sieved in an inert gas protective atmosphere to obtain high-entropy alloy powder with a particle size of 40 to 50 micrometers.

[0071] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​ZrC with a particle size range of 40 to 50 micrometers and a coating thickness of 30 micrometers.

[0072] The surface-coated ceramic powder is a nickel-plated ceramic powder. The nickel plating process is as follows:

[0073] (i) Sensitization and activation: Add ceramic powder at a rate of 30 g / L to a sensitization and activation solution at 30 °C, stir at a speed of 50 r / min for 10 min, wash with water, filter, and obtain sensitized and activated ceramic powder.

[0074] (ii) Electroless nickel plating: The sensitized and activated ceramic powder was added to the electroless nickel plating solution at a rate of 5 g / L, ultrasonically vibrated for 50 min, cleaned, and dried to obtain nickel-plated ceramic powder; the temperature of the plating solution was maintained at 30℃, the pH value of the plating solution was 8, and the concentration of NiCl2 in the electroless nickel plating solution was 0.3 mol / L and the concentration of NiSO4 was 0.1 mol / L.

[0075] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 4:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, the amount of which is 1.5 times the weight of the mixture of the two powders; the ball milling speed is 50 r / min, the ball milling time is 6 h, the ball-to-powder ratio is 5:1, dry, and sieve to obtain ceramic alloy powder.

[0076] Example 5

[0077] A method for preparing ceramic alloy powder:

[0078] Step 1: High-entropy alloy powder is prepared by atomization. The high-entropy alloy powder is composed of Co, Cr, Fe, Mn and Zr, and the molar ratio of the corresponding elements is 0.8:1:1:1:1.

[0079] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted four times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 4 × 10⁻⁶.-4 The melting power was 40kW, the atomization pressure was 10MPa, the liquid flow rate was 10kg / min, the atomization nozzle diameter was 5mm, and after atomization, the powder was allowed to cool completely and then sieved in an inert gas protective atmosphere to obtain high-entropy alloy powder with a particle size of 20 to 30 micrometers.

[0080] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​either TiC or ZrC, the particle size of the ceramic powder matrix is ​​20 to 40 micrometers, and the coating thickness is 20 micrometers.

[0081] The surface-coated ceramic powder is a nickel-plated ceramic powder. The nickel plating process is as follows:

[0082] (i) Sensitization and activation: Add ceramic powder at a rate of 20 g / L to a sensitization and activation solution at 20 °C, stir at a speed of 40 r / min for 6 min, wash with water, filter, and obtain sensitized and activated ceramic powder.

[0083] (ii) Electroless nickel plating: Sensitized and activated ceramic powder is added to the electroless nickel plating solution at a rate of 5 g / L, ultrasonically vibrated for 40 min, cleaned, and dried to obtain nickel-plated ceramic powder; the temperature of the plating solution is maintained at 40℃, the pH value of the plating solution is 8, and the concentration of NiCl2 in the electroless nickel plating solution is 0.3 mol / L and the concentration of NiSO4 is 0.1 mol / L.

[0084] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 4:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, the amount of which is 1.5 times the weight of the mixture of the two powders; the ball milling speed is 50 r / min, the ball milling time is 6 h, the ball-to-powder ratio is 4:1, dry, and sieve to obtain ceramic alloy powder.

[0085] Comparative Example 1

[0086] Comparison: The core difference compared to Example 1 lies in the composition of the high-entropy alloy powder.

[0087] A method for preparing ceramic alloy powder:

[0088] Step 1: High-entropy alloy powder is prepared by atomization. The high-entropy alloy powder is composed of Co, Cr, Fe, Mn and Ni, and the molar ratio of the corresponding elements is 0.5:1:1:1:1.

[0089] Comparative Example 2

[0090] Comparison: The core difference compared to Example 1 lies in the atomization powder production process.

[0091] Under inert gas protection, Co, Cr, Fe, Mn, and Zr with a purity ≥ 99.9% were mixed and repeatedly smelted five times, followed by atomization using nitrogen or argon as the atomizing medium; the vacuum degree during atomization powder production was 5 × 10⁻⁶. -4 The melting power was 50kW, the atomization pressure was 3MPa, the liquid flow rate was 30kg / min, the atomization nozzle diameter was 15mm, and after atomization, the powder was completely cooled and then sieved in an inert gas protective atmosphere to obtain high entropy alloy powder with a particle size of 70 to 90 micrometers.

[0092] Comparative Example 3

[0093] Comparison: The key difference compared to Example 2 is that the ceramic powder is not surface coated.

[0094] Step 2: Weigh the ceramic powder. The ceramic powder matrix is ​​B4C, the particle size range of the ceramic powder matrix is ​​70 to 80 micrometers, and the coating thickness is 30 micrometers.

[0095] Step 3: Weigh the high-entropy alloy powder from Step 1 and the ceramic powder from Step 2 separately at a mass ratio of 6:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, and add an amount twice the weight of the mixture of the two powders; the ball milling speed is 60 r / min, the ball milling time is 6 h, the ball-to-powder ratio is 6:1, dry, and sieve to obtain ceramic alloy powder.

[0096] Comparative Example 4

[0097] Comparison: The core difference between Example 2 and Example 3 lies in the different nickel plating process on the ceramic powder surface.

[0098] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​B4C with a particle size range of 70 to 80 micrometers and a coating thickness of 30 micrometers.

[0099] The surface-coated ceramic powder is a nickel-plated ceramic powder. The nickel plating process is as follows:

[0100] Ceramic powder was added to 200 mL of plating solution at a concentration of 30 g / L and stirred for 5 minutes. Then, 50 mL of 0.04 mol / L NaBH4 solution was added, and stirring continued for 20 minutes. The mixture was filtered, washed with deionized water and anhydrous ethanol, and then vacuum dried at 60 °C for 6 hours to obtain nickel-plated ceramic powder. The plating solution contained 2.4 × 10⁻⁶ N·m³. -2 mol / L NiCl2 and 2.0×10 - 3 mol / L HCl.

[0101] Comparative Example 5

[0102] Comparison: The core difference between this example and Example 3 lies in the ball milling process.

[0103] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 5:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, and add an amount twice the weight of the mixture of the two powders; the ball milling speed is 200 r / min, the ball milling time is 8 h, the ball-to-powder ratio is 5:1, dry, and sieve to obtain ceramic alloy powder.

[0104] Comparative Example 6

[0105] Comparison: The core difference between this example and Example 3 lies in the ball milling process.

[0106] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 5:1; mix the two powders and add them to a ball mill jar for mixing. The ball milling speed is 50 r / min, the ball milling time is 8 h, the ball-to-material ratio is 5:1, dry, and sieve to obtain ceramic alloy powder.

[0107] Comparative Example 7

[0108] Comparison: The core difference compared to Example 4 is the mass ratio of high-entropy alloy powder to surface-coated ceramic powder.

[0109] Step 3: Weigh the high-entropy alloy powder from Step 1 and the surface-coated ceramic powder from Step 2 separately at a mass ratio of 9:1; mix the two powders and add them to a ball mill jar to form a slurry; perform wet ball milling with anhydrous ethanol or acetone as the grinding medium, the amount of which is 1.5 times the weight of the mixture of the two powders; the ball milling speed is 50 r / min, the ball milling time is 6 h, the ball-to-powder ratio is 5:1, dry, and sieve to obtain ceramic alloy powder.

[0110] Comparative Example 8

[0111] Comparison: The core difference compared to Example 5 lies in the choice of ceramic powder matrix.

[0112] Step 2: Prepare surface-coated ceramic powder. The ceramic powder matrix is ​​alumina, the particle size of the ceramic powder matrix ranges from 20 to 40 micrometers, and the coating thickness is 20 micrometers.

[0113] The surface-coated ceramic powder is a nickel-plated ceramic powder. The nickel plating process is as follows:

[0114] (i) Sensitization and activation: Add ceramic powder at a rate of 20 g / L to a sensitization and activation solution at 20 °C, stir at a speed of 40 r / min for 6 min, wash with water, filter, and obtain sensitized and activated ceramic powder.

[0115] (ii) Electroless nickel plating: Sensitized and activated ceramic powder is added to the electroless nickel plating solution at a rate of 5 g / L, ultrasonically vibrated for 40 min, cleaned, and dried to obtain nickel-plated ceramic powder; the temperature of the plating solution is maintained at 40℃, the pH value of the plating solution is 8, and the concentration of NiCl2 in the electroless nickel plating solution is 0.3 mol / L and the concentration of NiSO4 is 0.1 mol / L.

[0116] Performance testing

[0117] Sphericity: The sphericity of the powders obtained in the examples and comparative examples was tested according to GB / T 16418-2008, and the test results are shown in Table 1.

[0118] Flowability: The flowability of the powders obtained in the examples and comparative examples was tested according to GB / T 1482-2010 Standard for Determination of Flowability of Metal Powders - Funnel Method (Hall Flowmeter). The test results are shown in Table 1.

[0119] Table 1 Results of Ceramic Alloy Powder Sphericity and Flowability Tests

[0120]

[0121]

[0122] The ceramic alloy powders obtained in the examples and comparative examples were dried in a vacuum drying oven at 100℃ for 5 hours. A 100mm × 100mm × 10mm Q235 substrate was selected as the laser cladding substrate, and impurities on the substrate surface were removed by mechanical grinding. A 4% polyvinyl alcohol solution was added to the ceramic alloy powder and stirred until a uniform paste was formed. This paste was then coated onto the surface of the Q235 substrate, allowing the ceramic alloy powder to solidify into a 1mm thick pre-coated layer. Laser cladding technology was used under the following process parameters: laser power 1500W, scanning speed 5mm / s, spot diameter 4mm, defocusing amount 15mm, and argon protection flow rate 20L / min, to obtain a ceramic alloy powder-reinforced surface coating.

[0123] Hardness testing: Hardness testing was conducted using a Vickers microhardness tester. The test conditions were: a load of 0.3 kg was applied, and the pressure was held for 15 seconds. Three points were selected on the same horizontal plane at the same point for measurement. The microhardness at each horizontal position was taken as the average of the three points. The test results are shown in Table 2.

[0124] High-temperature oxidation test: The test samples were cleaned and placed in a box-type resistance air furnace for high-temperature oxidation test. The test temperature was 1200℃ and the test time was 48h. The weight gain per unit area was calculated based on the weight difference before and after the test. The results are shown in Table 2.

[0125] Table 2 Test Results of Ceramic Alloy Powder Products

[0126]

[0127]

[0128] The above embodiments are merely illustrative examples to clearly illustrate the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a ceramic alloy powder, characterized by: Step 1: preparing a high-entropy alloy powder by atomization, the high-entropy alloy powder being composed of Co, Cr, Fe, Mn, and Zr, and the corresponding element molar ratio being 0.5-0.8:1:1:1:1; Step 2: preparing a surface-coated ceramic powder, the ceramic powder substrate being one or more of TiC, B4C, and ZrC, the ceramic powder substrate having a particle size range of 20-80 microns, and the coating layer having a thickness of 20-30 microns; The surface-coated ceramic powder in Step 2 is a ceramic powder coated with nickel, and the surface nickel plating process is as follows: (i) Sensitization and activation: adding the ceramic powder to a sensitization and activation solution at a temperature of 20-30°C at a dosage of 20-30 g / L, stirring at a speed of 40-60 r / min for 6-10 min, washing with water, filtering, and obtaining sensitized and activated ceramic powder; (ii) Chemical nickel plating: adding the sensitized and activated ceramic powder to a chemical nickel plating solution at a dosage of 5-10 g / L, ultrasonic oscillation for 30-50 min, cleaning, and drying to obtain nickel-coated ceramic powder; the plating solution temperature is maintained at 30-50°C, the plating solution pH value is 8-10, and the chemical nickel plating solution contains 0.3-0.4 mol / L of NiCl2 and 0.1-0.2 mol / L of NiSO4; Step 3: weighing the high-entropy alloy powder of Step 1 and the surface-coated ceramic powder of Step 2 in a mass ratio of 4:1-6:1; mixing the two powders to form a slurry in a ball mill jar, wet ball milling, drying, and sieving to obtain a ceramic alloy powder; In Step 3, the two powders are mixed and then added to a ball mill jar to form a slurry, which is wet ball milled, the wet milling medium being anhydrous ethanol or acetone, and the amount of the medium added being 1.5-2 times the weight of the mixed powders; the ball milling speed is 50-60 r / min, the ball milling time is 6-12 h, the ball-to-powder ratio is 4:1-6:1, the slurry is dried, and sieved to obtain a ceramic alloy powder.

2. The method of claim 1, wherein the ceramic alloy powder is prepared by the steps of: In Step 1, the high-entropy alloy powder is composed of Co, Cr, Fe, Mn, and Zr, and the corresponding element molar ratio is 0.5-0.8:1:1:1:1, and the particle size is 20-50 microns. ​ 3. The method of claim 1, wherein the ceramic alloy powder is prepared by the steps of: In Step 1, the high-entropy alloy powder is composed of Co, Cr, Fe, Mn, and Zr, and the corresponding element molar ratio is 0.6:1:1:1:1, and the particle size is 30-40 microns. ​ 4. The method of claim 1, wherein the ceramic alloy powder is prepared by the steps of: In Step 2, the ceramic powder substrate has a particle size range of 40-50 microns. ​ 5. The method of claim 1, wherein the ceramic alloy powder is prepared by the steps of: In Step 1, the process for preparing the high-entropy alloy powder by atomization is as follows: ​ The Co, Cr, Fe, Mn and Zr with purity of 99.9% are mixed and repeatedly smelted for 3 to 5 times under inert gas protection, and then atomized by using nitrogen or argon as atomizing medium; the vacuum degree in atomizing powder production is 3×10 -4 to 5×10 -4 Pa, the smelting power is 30 to 50 kW, the atomizing pressure is 5 to 15 MPa, the liquid flow rate is 10 to 20 kg / min, the atomizing nozzle diameter is 5 to 10 mm, the powder is completely cooled after atomizing, and then screened in inert gas protection atmosphere, to obtain high-entropy alloy powder with particle size of 20 to 50 microns.

6. The method of claim 1, wherein the ceramic alloy powder is prepared by the steps of: In Step 1, the process for preparing the high-entropy alloy powder by atomization is as follows: ​ The Co, Cr, Fe, Mn and Zr with purity of 99.9% each are mixed and repeatedly smelted for 3 times under inert gas protection, and then atomized by using nitrogen or argon as atomizing medium; the vacuum degree in atomization powder production is 4x10 -4 Pa, smelting power is 40 kW, atomizing pressure is 10 MPa, liquid flow rate is 15 kg / min, atomizing nozzle diameter is 5 mm, after atomization, the powder is completely cooled, and then sieved in inert gas protection atmosphere, to obtain high-entropy alloy powder with particle size of 30-40 microns.

7. The method of claim 1, wherein the ceramic alloy powder is prepared by the steps of: In Step 2, the surface-coated ceramic powder is a ceramic powder coated with nickel, and the surface nickel plating process is as follows: ​ (i) Sensitization and activation: adding the ceramic powder to a sensitization and activation solution at a temperature of 30°C at a dosage of 20 g / L, stirring at a speed of 40 r / min for 10 min, washing with water, filtering, and obtaining sensitized and activated ceramic powder; (ii) electroless nickel plating: the sensitized and activated ceramic powder is added into the electroless nickel plating solution in an amount of 5 g / L, ultrasonic oscillation is performed for 50 min, washing, drying, to obtain the nickel plated ceramic powder; the plating solution temperature is kept at 50°C, the plating solution pH value is 9, the electroless nickel plating solution contains 0.35 mol / L of NiCl2 and 0.15 mol / L of NiSO4.

8. The method of claim 1, wherein the ceramic alloy powder is prepared by the steps of: The two kinds of powders after mixing in step 3 are added into a ball mill tank to form a slurry, wet ball milling is performed, the wet milling medium is anhydrous ethanol, the amount of addition is 2 times the weight of the mixed powders; the ball milling speed is 50 r / min, the ball milling time is 8 h, the ball-to-powder ratio is 5:1, drying, sieving, to obtain the ceramic alloy powder. ​

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