An iron-based alloy powder and a method for producing the same

Abstract

The application relates to the technical field of alloy materials, in particular to an iron-based alloy powder and a preparation method thereof, which comprises an iron-based alloy body and a surface modification component coated on the surface of the iron-based alloy body; the chemical composition of the iron-based alloy body comprises, in percentage by mass, Cr: 18-22%, Mo: 3-5%, W+V: 3-6%, Ti: 0.8-1.5%, Ce: 0.5-1%, C: 2.5-3.5%, and the balance is Fe and inevitable impurities. The preparation method of the iron-based alloy powder comprises the following steps: step 1, preparing alloy powder material; after vacuum induction smelting of the alloy powder material, the alloy powder material is subjected to gas atomization powdering to obtain the iron-based alloy body; and step 2, adding the surface modification component to the iron-based alloy body, and adopting dispersion coating treatment and low-temperature crystallization stabilization treatment to obtain the iron-based alloy powder. The prepared iron-based alloy powder has stable mechanical properties, outstanding oxidation resistance and wear resistance, and good forming performance.

Description

Technical Field

[0001] This application relates to the field of alloy materials technology, and more specifically, to an iron-based alloy powder and its preparation method. Background Technology

[0002] Hydraulic supports are core equipment in fully mechanized coal mining. Their key components, such as the uprights, are subjected to complex conditions of high loads, strong corrosion, and coal and rock impacts underground for extended periods, making their surfaces highly susceptible to wear and corrosion failure, severely impacting the safety and efficiency of fully mechanized mining operations. Laser cladding technology, due to its strong coating adhesion and excellent performance, has become the mainstream method for surface protection of key components of hydraulic supports. The performance of the cladding powder directly determines the protective effect.

[0003] Currently, most laser cladding in the industry uses nickel-based alloy powders. While these powders possess some corrosion resistance, they also have significant drawbacks: high cost; low hardness, making them unable to withstand high-load wear in downhole environments; and a large difference in thermal expansion coefficients compared to steel substrates, easily leading to coating cracking. Existing iron-based laser cladding powders, although inexpensive, generally suffer from the technical challenge of inverted hardness and toughness, resulting in low carbide formation rates and low cladding layer density. Furthermore, they exhibit poor powder flowability and wettability, leading to uneven spreading during laser cladding and weak adhesion between the coating and the substrate. Additionally, poor oxygen content control results in numerous oxide inclusions, making it difficult to meet the corrosion resistance requirements of downhole conditions and unsuitable for the protection needs of hydraulic supports. Therefore, developing a high-hardness, high-toughness, corrosion-resistant, and highly flowable iron-based laser cladding powder to address the performance shortcomings of existing materials and reduce the protection costs of hydraulic supports has become an urgent technical problem to be solved in this field. Summary of the Invention

[0004] To address the technical problems mentioned in the background section, this application provides an iron-based alloy powder and its preparation method.

[0005] This application provides an iron-based alloy powder, employing the following technical solution:

[0006] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18-22%, Mo: 3-5%, W+V: 3-6%, Ti: 0.8-1.5%, Ce: 0.5-1%, C: 2.5-3.5%, with the balance being Fe and unavoidable impurities; the surface-modifying component consists of a surfactant and a lubricant in a mass ratio of 10-12:5-7.

[0007] Preferably, the chemical composition also satisfies the following quantitative relationship: 0.1≤[C] / ([Cr]+[Mo]+[W+V]+[Ti])≤0.12; wherein [C], [Cr], [Mo], [W+V], and [Ti] are the mass percentage contents of C, Cr, Mo, W+V, and Ti, respectively.

[0008] Preferably, the mass ratio of W to V in the chemical composition is 4-8:1-3.

[0009] Preferably, the surfactant is one or more of titanate coupling agents, polyoxyethylene stearate, and γ-aminopropyltriethoxysilane.

[0010] Preferably, the lubricant is one or more of nano zinc stearate, microcrystalline wax powder, and polytetrafluoroethylene powder.

[0011] This application also provides a method for preparing iron-based alloy powder, which adopts the following technical solution;

[0012] A method for preparing iron-based alloy powder includes the following preparation steps:

[0013] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder and graphite powder according to the mass percentage, and then vacuum dry, crush and sieve, grind and mix to obtain alloy powder; after vacuum induction melting of alloy powder, gas atomization powder making, graded sieving and vacuum deoxygenation treatment are adopted to obtain iron-based alloy body.

[0014] Step 2: Add surface-modifying components to the iron-based alloy body, perform dispersion coating treatment, vacuum drying, low-temperature crystallization stabilization treatment, and sieve to obtain iron-based alloy powder.

[0015] Preferably, the vacuum induction melting in step 1 specifically involves: under a vacuum degree ≤ 5 Pa, heating from room temperature to 800-900℃ at a heating rate of 5-8℃ / min, holding for 10-15 min; then heating to 1350-1450℃ at a heating rate of 8-12℃ / min, holding for 15-20 min; and finally heating to 1580-1650℃ at a heating rate of 3-5℃ / min, holding for 20-30 min.

[0016] Preferably, in step 1, the atomizing medium for gas atomization powder production is argon, the atomization pressure is 6-8 MPa, and the temperature of the atomizing medium is controlled between -10℃ and 0℃.

[0017] Preferably, the vacuum deoxygenation process in step 1 specifically involves: maintaining the temperature for 2-3 hours under conditions of vacuum degree ≤ 5 Pa and temperature of 200-250℃, followed by vacuum cooling to room temperature at a cooling rate of 15-20℃ / min.

[0018] Preferably, the amount of surface-modifying component added in step 2 is 0.8-1.5% of the mass of the iron-based alloy bulk.

[0019] Preferably, the low-temperature crystallization stabilization treatment in step 2 specifically involves heating to 120-150℃ at a heating rate of 3-5℃ / min, holding at that temperature for 1-2 hours, and then naturally cooling to room temperature.

[0020] In summary, this application has the following beneficial effects:

[0021] In the preparation of iron-based alloy powder, this application strictly controls the ratio of [C] / ([Cr] + [Mo] + [W + V] + [Ti]). Precise control of this ratio is crucial for optimizing the microstructure and mechanical properties of the alloy powder. Carbon, as a strengthening element in the alloy, directly affects the precipitation morphology and distribution of carbides in proportion to alloying elements such as Cr and Mo. An excessively high ratio leads to coarse carbide aggregation, reducing the alloy's toughness and formability; an excessively low ratio fails to adequately form strengthening carbides, resulting in insufficient hardness and wear resistance. This application achieves a reasonable ratio, ensuring that carbides are evenly and finely distributed in the matrix, guaranteeing both the high hardness of the alloy powder and improving its formability and toughness. Furthermore, by strictly controlling the mass ratio of W and V, their synergistic strengthening effect can be fully utilized. W enhances the high-temperature hardness and wear resistance of the alloy, while V refines the grains and promotes carbide precipitation. Together, they form a synergistic strengthening effect, significantly improving the wear resistance and oxidation resistance of the alloy powder.

[0022] This application effectively improves the purity and compositional uniformity of alloy powder through precise control of the vacuum induction melting process. The application employs segmented heating and precise heat preservation to avoid oxidation and segregation of alloying elements, while simultaneously removing impurities and gases from the raw materials, resulting in a uniform distribution of alloy composition. Low-temperature crystallization stabilization treatment refines the alloy grains and stabilizes their structure, preventing performance fluctuations caused by coarse grains, and also improving the bulk density and flowability of the alloy powder. Detailed Implementation

[0023] The present application will be further described in detail below with reference to the embodiments.

[0024] The polyoxyethylene stearate used in the embodiments and comparative examples of this application was purchased from Nantong Renda Chemical Co., Ltd.; the microcrystalline wax powder (brand name: J0227) was purchased from Jining Tangyi Chemical Co., Ltd.; the Ce powder was purchased from Ganzhou Qiming New Materials Co., Ltd.; and the graphite powder (particle size: 0.01mm) was purchased from Shijiazhuang Yuanjing Mineral Products Co., Ltd.

[0025] Examples 1-3 provide an iron-based alloy powder and its preparation method.

[0026] Example 1

[0027] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18%, Mo: 3%, W + V: 3%, Ti: 1%, Ce: 0.5%, C: 2.5%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 4:1, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 10:5.

[0028] A method for preparing iron-based alloy powder includes the following preparation steps:

[0029] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 80℃ for 2 hours and pulverizing through a 100-mesh sieve, grind and mix the powder using high-hardness ceramic balls as the grinding medium at a ball-to-powder ratio of 4:1 and a grinding speed of 300 rpm for 2 hours to obtain alloy powder. Under a vacuum of 5 Pa, heat the alloy powder from room temperature to 800℃ at a heating rate of 5℃ / min and hold for 10 minutes; then heat it to 1350℃ at a heating rate of 8℃ / min and hold for 15 minutes; finally, heat it to 1580℃ at a heating rate of 3℃ / min and hold for 20 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 6 MPa and a temperature of -10℃, using a double-layer standard sieve at a vibration frequency of 20 Hz and an amplitude of 1. The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 200℃ for 2 hours under vacuum of 5Pa and temperature of 200℃. Then, it was vacuum cooled to room temperature at a cooling rate of 15℃ / min.

[0030] Step 2: Control the amount of surface modification component added to 0.8% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 900 rpm for 30 min. After vacuum drying at 5 Pa and 60 °C for 3 h, heat it to 120 °C at a heating rate of 3 °C / min, hold it at that temperature for 1 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0031] Example 2

[0032] An iron-based alloy powder comprises an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, comprises the following chemical composition: Cr: 20%, Mo: 4%, W + V: 4%, Ti: 1.2%, Ce: 0.8%, C: 3%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 6:2, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 11:6.

[0033] A method for preparing iron-based alloy powder includes the following preparation steps:

[0034] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 90℃ for 3 hours and pulverizing through a 150-mesh sieve, grind and mix using high-hardness ceramic balls as the grinding medium at a ball-to-material ratio of 5:1 and a grinding speed of 350 rpm for 2.5 hours to obtain alloy powder. Under a vacuum of 3 Pa, heat the alloy powder from room temperature to 850℃ at a heating rate of 7℃ / min and hold for 12 minutes; then heat it to 1400℃ at a heating rate of 10℃ / min and hold for 18 minutes; finally, heat it to 1620℃ at a heating rate of 4℃ / min and hold for 25 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 7 MPa and a temperature of -5℃, using a double-layer standard sieve with a vibration frequency of 35 Hz and an amplitude of 2... The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 225℃ for 2.5h under vacuum of 1Pa and temperature of 225℃. Then, it was vacuum cooled to room temperature at a cooling rate of 18℃ / min to obtain the iron-based alloy body.

[0035] Step 2: Control the amount of surface modification component added to 1% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 1000 rpm for 35 min. After vacuum drying at 70℃ and 1 Pa for 4 h, heat it to 135℃ at a heating rate of 4℃ / min, hold it at that temperature for 1.5 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0036] Example 3

[0037] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 20%, Mo: 4%, W + V: 5%, Ti: 1%, Ce: 1%, C: 3.5%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 8:3, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 12:7.

[0038] A method for preparing iron-based alloy powder includes the following preparation steps:

[0039] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 100℃ for 4 hours and pulverizing through a 200-mesh sieve, grind and mix the powder using high-hardness ceramic balls as the grinding medium at a ball-to-powder ratio of 6:1 and a grinding speed of 400 rpm for 3 hours to obtain alloy powder. Under a vacuum of 1 Pa, heat the alloy powder from room temperature to 900℃ at a heating rate of 8℃ / min and hold for 15 minutes; then heat it to 1450℃ at a heating rate of 12℃ / min and hold for 20 minutes; finally, heat it to 1650℃ at a heating rate of 5℃ / min and hold for 30 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 8 MPa and a temperature of 0℃. Use a double-layer standard sieve and a vibration frequency of 50 Hz and an amplitude of 3... The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 250℃ for 3 hours under vacuum of 1Pa and temperature of 250℃. Then, it was vacuum cooled to room temperature at a cooling rate of 20℃ / min.

[0040] Step 2: Control the amount of surface modification component added to 1.5% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 1100 rpm for 40 min. After vacuum drying at 1 Pa and 80 °C for 5 h, heat it to 150 °C at a heating rate of 5 °C / min, hold it at that temperature for 2 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0041] Comparative Example 1

[0042] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18%, Mo: 3%, W + V: 3%, Ti: 1%, Ce: 0.5%, C: 2%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 4:1, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 10:5.

[0043] A method for preparing iron-based alloy powder includes the following preparation steps:

[0044] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 80℃ for 2 hours and pulverizing through a 100-mesh sieve, grind and mix the powder using high-hardness ceramic balls as the grinding medium at a ball-to-powder ratio of 4:1 and a grinding speed of 300 rpm for 2 hours to obtain alloy powder. Under a vacuum of 5 Pa, heat the alloy powder from room temperature to 800℃ at a heating rate of 5℃ / min and hold for 10 minutes; then heat it to 1350℃ at a heating rate of 8℃ / min and hold for 15 minutes; finally, heat it to 1580℃ at a heating rate of 3℃ / min and hold for 20 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 6 MPa and a temperature of -10℃, using a double-layer standard sieve at a vibration frequency of 20 Hz and an amplitude of 1. The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 200℃ for 2 hours under vacuum of 5Pa and temperature of 200℃. Then, it was vacuum cooled to room temperature at a cooling rate of 15℃ / min.

[0045] Step 2: Control the amount of surface modification component added to 0.8% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 900 rpm for 30 min. After vacuum drying at 5 Pa and 60 °C for 3 h, heat it to 120 °C at a heating rate of 3 °C / min, hold it at that temperature for 1 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0046] Comparative Example 2

[0047] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18%, Mo: 3%, W + V: 3%, Ti: 1%, Ce: 0.5%, C: 3.75%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 4:1, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 10:5.

[0048] A method for preparing iron-based alloy powder includes the following preparation steps:

[0049] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 80℃ for 2 hours and pulverizing through a 100-mesh sieve, grind and mix the powder using high-hardness ceramic balls as the grinding medium at a ball-to-powder ratio of 4:1 and a grinding speed of 300 rpm for 2 hours to obtain alloy powder. Under a vacuum of 5 Pa, heat the alloy powder from room temperature to 800℃ at a heating rate of 5℃ / min and hold for 10 minutes; then heat it to 1350℃ at a heating rate of 8℃ / min and hold for 15 minutes; finally, heat it to 1580℃ at a heating rate of 3℃ / min and hold for 20 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 6 MPa and a temperature of -10℃, using a double-layer standard sieve at a vibration frequency of 20 Hz and an amplitude of 1. The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 200℃ for 2 hours under vacuum of 5Pa and temperature of 200℃. Then, it was vacuum cooled to room temperature at a cooling rate of 15℃ / min.

[0050] Step 2: Control the amount of surface modification component added to 0.8% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 900 rpm for 30 min. After vacuum drying at 5 Pa and 60 °C for 3 h, heat it to 120 °C at a heating rate of 3 °C / min, hold it at that temperature for 1 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0051] Comparative Example 3

[0052] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18%, Mo: 3%, W + V: 3%, Ti: 1%, Ce: 0.5%, C: 2.5%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 1:4, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 10:5.

[0053] A method for preparing iron-based alloy powder includes the following preparation steps:

[0054] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 80℃ for 2 hours and pulverizing through a 100-mesh sieve, grind and mix the powder using high-hardness ceramic balls as the grinding medium at a ball-to-powder ratio of 4:1 and a grinding speed of 300 rpm for 2 hours to obtain alloy powder. Under a vacuum of 5 Pa, heat the alloy powder from room temperature to 800℃ at a heating rate of 5℃ / min and hold for 10 minutes; then heat it to 1350℃ at a heating rate of 8℃ / min and hold for 15 minutes; finally, heat it to 1580℃ at a heating rate of 3℃ / min and hold for 20 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 6 MPa and a temperature of -10℃, using a double-layer standard sieve at a vibration frequency of 20 Hz and an amplitude of 1. The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 200℃ for 2 hours under vacuum of 5Pa and temperature of 200℃. Then, it was vacuum cooled to room temperature at a cooling rate of 15℃ / min.

[0055] Step 2: Control the amount of surface modification component added to 0.8% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 900 rpm for 30 min. After vacuum drying at 5 Pa and 60 °C for 3 h, heat it to 120 °C at a heating rate of 3 °C / min, hold it at that temperature for 1 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0056] Comparative Example 4

[0057] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18%, Mo: 3%, W + V: 3%, Ti: 1%, Ce: 0.5%, C: 2.5%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 4:1, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 10:5.

[0058] A method for preparing iron-based alloy powder includes the following preparation steps:

[0059] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. Dry them under vacuum at 80℃ for 2 hours, then pulverize them through a 100-mesh sieve. Using high-hardness ceramic balls as the grinding medium, with a ball-to-material ratio of 4:1 and a grinding speed of 300 rpm, grind and mix for 2 hours to obtain alloy powder. Under a vacuum of 5 Pa, heat the alloy powder from room temperature to 800℃ at a heating rate of 5℃ / min, holding for 10 minutes; then heat it to 1350℃ at a heating rate of 5℃ / min, holding for 15 minutes; finally, heat it to 1580℃ at a heating rate of 5℃ / min, holding for 20 minutes. After vacuum induction melting, use gas atomization to produce powder. Powder production is carried out under argon protection at an atomization pressure of 6 MPa and a temperature of -10℃, using a double-layer standard sieve with a vibration frequency of 20 Hz and an amplitude of 1... The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 200℃ for 2 hours under vacuum of 5Pa and temperature of 200℃. Then, it was vacuum cooled to room temperature at a cooling rate of 15℃ / min.

[0060] Step 2: Control the amount of surface modification component added to 0.8% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 900 rpm for 30 min. After vacuum drying at 5 Pa and 60 °C for 3 h, heat it to 120 °C at a heating rate of 3 °C / min, hold it at that temperature for 1 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0061] Comparative Example 5

[0062] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18%, Mo: 3%, W + V: 3%, Ti: 1%, Ce: 0.5%, C: 2.5%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 4:1, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 10:5.

[0063] A method for preparing iron-based alloy powder includes the following preparation steps:

[0064] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 80℃ for 2 hours and pulverizing through a 100-mesh sieve, grind and mix the powder using high-hardness ceramic balls as the grinding medium at a ball-to-powder ratio of 4:1 and a grinding speed of 300 rpm for 2 hours to obtain alloy powder. Under a vacuum of 5 Pa, heat the alloy powder from room temperature to 800℃ at a heating rate of 5℃ / min and hold for 10 minutes; then heat it to 1350℃ at a heating rate of 8℃ / min and hold for 15 minutes; finally, heat it to 1580℃ at a heating rate of 3℃ / min and hold for 20 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 6 MPa and a temperature of -10℃, using a double-layer standard sieve at a vibration frequency of 20 Hz and an amplitude of 1. The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and then holding at 200℃ under vacuum for 2 hours. After vacuum cooling to room temperature, the iron-based alloy body was obtained.

[0065] Step 2: Control the amount of surface modification component added to 0.8% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at 900 rpm for 30 min. After vacuum drying at 5 Pa and 60 °C for 3 h, heat it to 120 °C at a heating rate of 3 °C / min, hold it at that temperature for 1 h, and then cool it naturally to room temperature to obtain iron-based alloy powder.

[0066] Comparative Example 6

[0067] A type of iron-based alloy powder includes an iron-based alloy body and a surface-modifying component coated on the surface of the iron-based alloy body; the iron-based alloy body, by mass percentage, has the following chemical composition: Cr: 18%, Mo: 3%, W + V: 3%, Ti: 1%, Ce: 0.5%, C: 2.5%, with the balance being Fe and unavoidable impurities, wherein the mass ratio of W to V in the chemical composition is 4:1, and the surface-modifying component is composed of polyoxyethylene stearate and microcrystalline wax powder in a mass ratio of 10:5.

[0068] A method for preparing iron-based alloy powder includes the following preparation steps:

[0069] Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder, and graphite powder according to their mass percentages. After vacuum drying at 80℃ for 2 hours and pulverizing through a 100-mesh sieve, grind and mix the powder using high-hardness ceramic balls as the grinding medium at a ball-to-powder ratio of 4:1 and a grinding speed of 300 rpm for 2 hours to obtain alloy powder. Under a vacuum of 5 Pa, heat the alloy powder from room temperature to 800℃ at a heating rate of 5℃ / min and hold for 10 minutes; then heat it to 1350℃ at a heating rate of 8℃ / min and hold for 15 minutes; finally, heat it to 1580℃ at a heating rate of 3℃ / min and hold for 20 minutes. After vacuum induction melting, use gas atomization to produce powder under argon protection at an atomization pressure of 6 MPa and a temperature of -10℃, using a double-layer standard sieve at a vibration frequency of 20 Hz and an amplitude of 1. The iron-based alloy body was obtained by grading and sieving under the conditions of 150 mesh upper screen and 325 mesh lower screen, and holding at 200℃ for 2 hours under vacuum of 5Pa and temperature of 200℃. Then, it was vacuum cooled to room temperature at a cooling rate of 15℃ / min.

[0070] Step 2: Control the amount of surface modification component added to 0.8% of the mass of the iron-based alloy body. Add the surface modification component to the iron-based alloy body, and under argon protection, disperse and coat it at a speed of 900 rpm for 30 min. After vacuum drying at a vacuum degree of 5 Pa and a temperature of 60℃ for 3 h, it is naturally cooled to room temperature to obtain iron-based alloy powder.

[0071] Performance testing

[0072] The performance of the iron-based alloy powders prepared in Examples 1-3 and Comparative Examples 1-6 of this application was tested, and the specific test methods are as follows:

[0073] Hardness: Vickers hardness tester (HV) was used, and the test was conducted in accordance with the national standard GB / T 4340.1-2024 "Metallic materials Vickers hardness test - Part 1: Test method" at room temperature with a test load of 300g and a holding time of 10s.

[0074] Loose packing density: The test was conducted in accordance with the national standard GB / T 1479.1-2011 "Determination of loose packing density of metal powders - Part 1: Funnel method";

[0075] Flowability: Tested according to national standard GB / T 1482-2022 "Determination of Flowability of Metal Powders - Standard Funnel Method (Hall Flowmeter)";

[0076] Compressive strength: The iron-based alloy powders obtained in Examples 1-3 and Comparative Examples 1-6 were pressed into φ10mm×10mm compacts (pressing pressure of 300MPa). The compressive strength of the compacts was tested using a universal testing machine in accordance with the national standard GB / T 11106-2022 "Method for determining the compressive strength of cylindrical compacts for metal powder".

[0077] Antioxidant properties: The iron-based alloy powders obtained in Examples 1-3 and Comparative Examples 1-6 were placed in a muffle furnace and kept at a constant temperature of 1000℃ for 24 hours. The oxidation weight gain (mg / cm²) of the samples was calculated by gravimetric method. The smaller the oxidation weight gain, the better the antioxidant properties.

[0078] Wear resistance: Take 5g of the iron-based alloy powder prepared in Examples 1-3 and Comparative Examples 1-6, press it into a circular blank with a diameter of 10mm and a thickness of 5mm under a pressure of 300MPa, and use a pin-disc wear tester. The test conditions are: load 50N, wear speed 200rpm, wear time 1h, and wear medium is SiC sandpaper (800 mesh). After the test, weigh the mass difference (mg) of the sample before and after wear. The smaller the wear amount, the better the wear resistance.

[0079] The test results are shown in Table 1.

[0080] Table 1 Performance parameters of the iron-based alloy powders prepared in Examples 1-3 and Comparative Examples 1-6

[0081]

[0082] As shown in Table 1, the iron-based alloy powders prepared in Examples 1-3 of this application exhibit stable mechanical properties, outstanding oxidation resistance and wear resistance, and good formability. By optimizing the chemical composition ratio and preparation process, this iron-based alloy powder solves the problems of poor mechanical properties, insufficient wear resistance, and insufficient oxidation resistance found in conventional alloy powders. It can meet the preparation requirements of high-end wear-resistant and corrosion-resistant parts and has strong practicality.

[0083] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A type of iron-based alloy powder, characterized in that, It includes a steel-based alloy body and surface-modifying components coated on the surface of the steel-based alloy body; the steel-based alloy body has the following chemical composition by mass percentage: The composition includes: Cr: 18-22%, Mo: 3-5%, W+V: 3-6%, Ti: 0.8-1.5%, Ce: 0.5-1%, C: 2.5-3.5%, with the balance being Fe and unavoidable impurities; the surface-modifying component consists of a surfactant and a lubricant in a mass ratio of 10-12:5-7; the chemical composition also satisfies the following quantitative relationship: 0.1 ≤ [C] / ([Cr] + [Mo] + [W+V] + [Ti]) ≤ 0.12; where [C], [Cr], [Mo], [W+V], and [Ti] are the mass percentage contents of C, Cr, Mo, W+V, and Ti, respectively. The mass ratio of W to V in the chemical composition is 4-8:1-3; The method for preparing the iron-based alloy powder includes the following preparation steps: Step 1: Weigh Fe powder, Cr powder, Mo powder, W powder, V powder, Ti powder, Ce powder and graphite powder according to the mass percentage, and then vacuum dry, crush and sieve, grind and mix to obtain alloy powder; after vacuum induction melting of alloy powder, gas atomization powder making, graded sieving and vacuum deoxygenation treatment are adopted to obtain iron-based alloy body. Step 2: Add surface-modifying components to the iron-based alloy body, perform dispersion coating treatment, vacuum drying, low-temperature crystallization stabilization treatment, and sieve to obtain iron-based alloy powder; The vacuum induction melting in step 1 is specifically as follows: under a vacuum degree ≤ 5 Pa, the temperature is increased from room temperature to 800-900℃ at a heating rate of 5-8℃ / min, and held for 10-15 min; then the temperature is increased to 1350-1450℃ at a heating rate of 8-12℃ / min, and held for 15-20 min; finally, the temperature is increased to 1580-1650℃ at a heating rate of 3-5℃ / min, and held for 20-30 min. The vacuum deoxygenation process in step 1 is specifically as follows: under conditions of vacuum degree ≤ 5Pa and temperature of 200-250℃, the temperature is kept for 2-3 hours, and then vacuum cooled to room temperature at a cooling rate of 15-20℃ / min. The low-temperature crystallization stabilization treatment in step 2 specifically involves heating the temperature to 120-150℃ at a rate of 3-5℃ / min, holding it at that temperature for 1-2 hours, and then allowing it to cool naturally to room temperature.

2. The iron-based alloy powder according to claim 1, characterized in that, The surfactant is one or more of titanate coupling agent, polyoxyethylene stearate, and γ-aminopropyltriethoxysilane; the lubricant is one or more of nano zinc stearate, microcrystalline wax powder, and polytetrafluoroethylene powder.

3. The iron-based alloy powder according to claim 1, characterized in that, In step 1, the atomizing medium for gas atomization powder production is argon gas, the atomization pressure is 6-8 MPa, and the temperature of the atomizing medium is controlled between -10℃ and 0℃.

4. The iron-based alloy powder according to claim 1, characterized in that, In step 2, the amount of surface-modifying component added is 0.8-1.5% of the mass of the iron-based alloy bulk.

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