Preparation method of high-performance iron-based alloy powder and application thereof
Patent Information
- Application Number
- CN202611108681.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-24
- Publication Date
- 2026-09-25
AI Technical Summary
[0006]为了克服上述背景技术中存在的铁基合金粉末易氧化团聚、颗粒界面结合能力不足以及烧结致密性较差的难题，本发明的目的在于提供一种高性能铁基合金粉末的制备方法及其应用，采用植酸-苯并咪唑-钛氧簇协同限域改性结构对铁基合金粉末表面进行协同包覆改性，并结合2,7-二羟基芴对颗粒界面电子结构进行调控，从而提高粉末的界面稳定性与烧结扩散能力，进而带来粉末流动性、烧结致密性及耐磨性能显著提升的有益效果
本发明采用植酸-苯并咪唑-钛氧簇协同限域结构对铁基合金粉末表面进行改性，其中植酸中的多磷酸基能够与铁基合金颗粒表面形成稳定配位吸附层，从而提高粉末表面的抗氧化稳定性；苯并咪唑中的含氮芳香杂环结构能够增强颗粒界面的电子迁移能力与烧结润湿性能，有利于提高颗粒间扩散结合效果；钛氧簇结构通过水解缩合形成稳定的无机限域网络，可进一步增强改性层的热稳定性与界面结合强度，三者协同作用能够在铁基合金粉末表面形成兼具柔性配位结构与刚性无机骨架的复合限域层，从而有效降低粉末团聚现象并提高颗粒分散均匀性。与此同时，本发明首次将2,7-二羟基芴应用于铁基合金粉末体系中，利用其刚性芳环结构及双羟基电子调控作用改善颗粒间界面能状态，促进烧结过程中的界面润湿与致密化扩散，从而降低孔隙缺陷形成概率，使所得铁基合金粉末在流动性、烧结致密性、力学强度及耐磨性能方面均得到显著提升，并表现出良好的高温稳定性与加工适应性。本发明采用含钒铁基预合金粉末作为基体，钒元素能够在烧结过程中促进晶粒细化，并提高铁素体及马氏体组织稳定性，同时能够提高烧结组织硬度及耐磨性能，与植酸-苯并咪唑-钛氧簇协同限域改性层形成协同强化作用，使所得铁基合金粉末具有更优异的综合力学性能及高温服役稳定性。
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Abstract
Description
Technical Field
[0001] This invention relates to the field of metal powder materials technology, specifically to a method for preparing high-performance iron-based alloy powder and its application. Background Technology
[0002] Iron-based alloy powders are widely used in powder metallurgy structural parts, metal injection molding, laser cladding, and additive manufacturing due to their low cost, excellent mechanical properties, good wear resistance, and wide applicability. With the continuous development of high-end equipment manufacturing and precision forming technology, the market has placed higher demands on the flowability, sintering density, interfacial bonding strength, and oxidation resistance of iron-based alloy powders.
[0003] Existing iron-based alloy powders still have certain limitations in practical applications. On the one hand, iron-based alloy powders have high surface activity and are prone to oxidation and agglomeration during storage and processing, which leads to a decrease in powder flowability and further affects the uniformity of subsequent forming. On the other hand, traditional iron-based alloy powders have limited interparticle diffusion ability during sintering or laser melting, which easily forms pores and interface defects, thereby reducing the material's density, mechanical strength, and wear resistance.
[0004] Currently, modification methods for iron-based alloy powders mainly focus on single silane coating, resin adsorption, or inorganic oxide deposition. While these methods can improve powder surface stability to some extent, they still suffer from insufficient interfacial bonding, poor high-temperature stability, and limited synergistic control capabilities. Furthermore, existing technologies have limited research on the application of small organic molecules with electronic control capabilities in the field of iron-based alloy powders, making it difficult to further enhance particle interfacial wetting and diffusion capabilities and sintering bonding performance.
[0005] Therefore, developing a high-performance iron-based alloy powder with a synergistic confined modification structure, excellent interfacial stability, and the ability to improve sintering density and wear resistance is of great significance for enhancing the overall performance of iron-based alloy powders and broadening their application range. Summary of the Invention
[0006] To overcome the problems of easy oxidation and agglomeration of iron-based alloy powders, insufficient interparticle bonding ability, and poor sintering density in the aforementioned background technologies, the present invention aims to provide a method for preparing high-performance iron-based alloy powders and their applications. This method employs a synergistic confined modification structure of phytic acid-benzimidazole-titanium oxide clusters to synergistically coat and modify the surface of the iron-based alloy powder, and combines this with 2,7-dihydroxyfluorene to regulate the electronic structure of the particle interface, thereby improving the interfacial stability and sintering diffusion ability of the powder. This results in a significant improvement in powder flowability, sintering density, and wear resistance.
[0007] The objective of this invention can be achieved through the following technical solutions: A high-performance iron-based alloy powder comprises the following raw materials in parts by weight: 80-150 parts of phytic acid-benzimidazole-titanium oxide cluster synergistic confined modification iron-based alloy powder; 1-10 parts of 2,7-dihydroxyfluorene; 0.5-5 parts of graphene; 1-6 parts of zinc stearate; 2-8 parts of polyethylene wax; 1-8 parts of nano-molybdenum disulfide; 0.5-3 parts of antioxidant; and 0.3-2 parts of leveling agent. The phytic acid-benzimidazole-titanium oxide cluster synergistic confined modification iron-based alloy powder is formed by synergistic modification of the iron-based alloy powder surface by coordination deposition and confined coating of phytic acid and benzimidazole under the action of titanium oxide cluster precursor. The iron-based alloy powder is a Fe-Cr-Ni-V pre-alloy powder, and the mass ratio of Fe, Cr, Ni and V in the Fe-Cr-Ni-V pre-alloy powder is (68-84):(10-20):(3-10):(0.2-2).
[0008] Optionally, the phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder comprises the following raw materials in parts by weight: 80-150 parts iron-based alloy powder; 5-25 parts phytic acid; 3-20 parts benzimidazole; 5-25 parts tetrabutyl titanate; 30-100 parts ethanol; and 40-150 parts deionized water.
[0009] Optionally, the preparation method of phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder includes the following steps: (1) Phytic acid and benzimidazole were added to a mixed solvent to carry out a mixed reaction to obtain a coordination precursor solution; (2) Add tetrabutyl titanate to the coordination precursor solution to carry out hydrolysis and condensation reaction to obtain phytic acid-benzimidazole-titanium oxide cluster synergistic modified solution; (3) The iron-based alloy powder is added to the phytic acid-benzimidazole-titanium oxide cluster synergistic modification liquid for coating modification, and then filtered, dried and pulverized to obtain the phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder.
[0010] Optionally, in step (1), phytic acid and benzimidazole are stirred and reacted at 30-60°C for 30-120 min.
[0011] Optionally, in step (2), the dropping rate of tetrabutyl titanate is 0.5 to 2 mL / min, the hydrolysis condensation reaction temperature is 40 to 75 °C, and the reaction time is 1 to 5 h.
[0012] Optionally, in step (3), the iron-based alloy powder and the phytic acid-benzimidazole-titanium oxide cluster synergistic modification liquid are coated and reacted at 50-80°C for 2-6 hours, and then dried at 80-120°C for 4-12 hours.
[0013] Optionally, the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of (1-3):1; the leveling agent is a mixture of polyether-modified polysiloxane and polyacrylate leveling agent in a mass ratio of 1:(1-4).
[0014] Optionally, a method for preparing high-performance iron-based alloy powder includes the following steps: S1, 2,7-dihydroxyfluorene, graphene, nano-molybdenum disulfide, zinc stearate, polyethylene wax, antioxidant and leveling agent are added to a mixed solvent for dispersion to obtain a functional additive dispersion; S2, phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder is added to the dispersion of the functional additive for mixing and coating treatment; S3 involves drying, granulating, and sieving the mixture to obtain high-performance iron-based alloy powder.
[0015] Optionally, in S1, the dispersion mixing speed is 400-1200 r / min, the dispersion temperature is 25-60℃, and the dispersion time is 20-90 min; in S2, the phytic acid-benzimidazole-titanium oxide cluster synergistic confined modified iron-based alloy powder and functional additive dispersion are mixed and coated at 40-75℃ for 1-5 h.
[0016] Optionally, the drying temperature in S3 is 70–110℃, the drying time is 3–10h, and the sieve mesh size is 200–500 mesh.
[0017] The beneficial effects of this invention are: This invention employs a synergistic confinement structure of phytic acid, benzimidazole, and titanium oxide clusters to modify the surface of iron-based alloy powders. The polyphosphate groups in phytic acid form a stable coordination adsorption layer on the surface of the iron-based alloy particles, thereby improving the oxidation stability of the powder surface. The nitrogen-containing aromatic heterocyclic structure in benzimidazole enhances the electron migration ability and sintering wettability of the particle interface, which is beneficial for improving the diffusion bonding effect between particles. The titanium oxide cluster structure forms a stable inorganic confinement network through hydrolysis and condensation, which further enhances the thermal stability and interfacial bonding strength of the modified layer. The synergistic effect of these three components forms a composite confinement layer on the surface of the iron-based alloy powder that combines a flexible coordination structure with a rigid inorganic framework, effectively reducing powder agglomeration and improving particle dispersion uniformity. Meanwhile, this invention is the first to apply 2,7-dihydroxyfluorene to an iron-based alloy powder system. Utilizing its rigid aromatic ring structure and the electronic regulation effect of its two hydroxyl groups, it improves the interfacial energy state between particles, promotes interfacial wetting and densification diffusion during sintering, thereby reducing the probability of porosity and defects. This significantly improves the fluidity, sintering density, mechanical strength, and wear resistance of the resulting iron-based alloy powder, while also exhibiting good high-temperature stability and processing adaptability. This invention uses vanadium-containing iron-based pre-alloyed powder as the matrix. Vanadium promotes grain refinement during sintering and improves the stability of ferrite and martensite structures. It also enhances the hardness and wear resistance of the sintered structure. Combined with the phytic acid-benzimidazole-titanium oxide cluster confined modification layer, it forms a synergistic strengthening effect, resulting in iron-based alloy powders with superior comprehensive mechanical properties and high-temperature service stability. Attached Figure Description
[0018] The invention will now be further described with reference to the accompanying drawings.
[0019] Figure 1 The image shows a comparison of the infrared spectra of iron-based alloy powder and iron-based alloy powder synergistically confined and modified with phytic acid-benzimidazole-titanium oxide cluster. Detailed Implementation
[0020] The present invention will be further described below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. Equivalent adjustments made without departing from the spirit and essence of the present invention should also be considered to fall within the protection scope of the present invention.
[0021] Example 1: The purpose of this example is to verify the effect of the phytic acid-benzimidazole-titanium oxide cluster synergistic confinement structure on the interface stability of iron-based alloy powder under low component content and low reaction conditions.
[0022] S1, 5 parts phytic acid and 3 parts benzimidazole were added to a mixed solvent consisting of 30 parts ethanol and 40 parts deionized water, and the mixture was stirred at 400 r / min for 30 min at 30 °C to obtain a coordination precursor solution; then 5 parts tetrabutyl titanate were added at a dropping rate of 0.5 mL / min, and a hydrolysis-condensation reaction was carried out at 40 °C for 1 h to obtain a phytic acid-benzimidazole-titanium oxide cluster synergistic modification solution; then 80 parts iron-based alloy powder were added, and a coating reaction was carried out at 50 °C for 2 h, followed by drying at 80 °C for 4 h and pulverization to obtain phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder; S2, 1 part of 2,7-dihydroxyfluorene, 0.5 part of graphene, 1 part of nano-molybdenum disulfide, 1 part of zinc stearate, 2 parts of polyethylene wax, 0.5 part of antioxidant and 0.3 part of leveling agent were added to a mixed solvent and dispersed and mixed at 400 r / min for 20 min at 25 °C to obtain a functional additive dispersion; then, phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder was added to the functional additive dispersion and mixed and coated at 40 °C for 1 h. S3. The resulting mixture is dried at 70°C for 3 hours, followed by granulation and 200-mesh sieving to obtain high-performance iron-based alloy powder.
[0023] Example 2: The purpose of this example is to verify the synergistic effect between the phytic acid-benzimidazole-titanium oxide cluster co-confined structure and 2,7-dihydroxyfluorene under moderate component content and moderate reaction conditions.
[0024] S1, 15 parts of phytic acid and 10 parts of benzimidazole were added to a mixed solvent consisting of 65 parts of ethanol and 95 parts of deionized water, and the mixture was stirred at 800 r / min for 75 min at 45 °C to obtain a coordination precursor solution; then 15 parts of tetrabutyl titanate were added at a dropping rate of 1 mL / min, and a hydrolysis-condensation reaction was carried out at 58 °C for 3 h to obtain a phytic acid-benzimidazole-titanium oxide cluster synergistic modification solution; then 115 parts of iron-based alloy powder were added, and a coating reaction was carried out at 65 °C for 4 h, followed by drying at 100 °C for 8 h and pulverization to obtain phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder. Figure 1Before modification, the Fe-Cr-Ni iron-based pre-alloyed powder showed only weak absorption peaks near 3430 cm⁻¹ and 560 cm⁻¹, indicating that only a small amount of hydroxyl groups and oxide layer structures existed on its surface. After modification, the sample showed significant enhanced peaks near 1140 cm⁻¹, 1050 cm⁻¹, and 950 cm⁻¹, indicating that a stable Ti-OP coordination structure was formed between the phosphate groups in phytic acid and the titanium oxide clusters. The appearance of characteristic peaks near 1540–1640 cm⁻¹ indicates that benzimidazole has been successfully introduced into the powder surface. At the same time, the Ti-O characteristic peaks near 660 cm⁻¹ and 460 cm⁻¹ further prove that the titanium oxide cluster confinement network has been formed, indicating that the phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modification structure has been successfully constructed on the surface of the iron-based alloy powder. S2, 5 parts of 2,7-dihydroxyfluorene, 2.5 parts of graphene, 4 parts of nano-molybdenum disulfide, 3 parts of zinc stearate, 5 parts of polyethylene wax, 1.5 parts of antioxidant and 1 part of leveling agent were added to a mixed solvent and dispersed and mixed at 800 r / min for 50 min at 40 °C to obtain a functional additive dispersion; then, phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder was added to the functional additive dispersion and mixed and coated at 58 °C for 3 h. S3. The resulting mixture is dried at 90°C for 6 hours, followed by granulation and 350-mesh sieving to obtain high-performance iron-based alloy powder.
[0025] Example 3: The purpose of this example is to verify the effect of the phytic acid-benzimidazole-titanium oxide cluster synergistic confinement structure on the high-temperature stability and densification properties of iron-based alloy powder under high component content and high reaction conditions.
[0026] S1, 25 parts of phytic acid and 20 parts of benzimidazole were added to a mixed solvent consisting of 100 parts of ethanol and 150 parts of deionized water, and the mixture was stirred at 1200 r / min for 120 min at 60 °C to obtain a coordination precursor solution; then 25 parts of tetrabutyl titanate were added at a dropping rate of 2 mL / min, and a hydrolysis-condensation reaction was carried out at 75 °C for 5 h to obtain a phytic acid-benzimidazole-titanium oxide cluster synergistic modification solution; then 150 parts of iron-based alloy powder were added, and a coating reaction was carried out at 80 °C for 6 h, followed by drying at 120 °C for 12 h and pulverization to obtain phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder; S2, 10 parts of 2,7-dihydroxyfluorene, 5 parts of graphene, 8 parts of nano-molybdenum disulfide, 6 parts of zinc stearate, 8 parts of polyethylene wax, 3 parts of antioxidant and 2 parts of leveling agent were added to a mixed solvent and dispersed and mixed at 1200 r / min for 90 min at 60 °C to obtain a functional additive dispersion; then, phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder was added to the functional additive dispersion and mixed and coated at 75 °C for 5 h; S3. The resulting mixture is dried at 110°C for 10 hours, followed by granulation and 500-mesh sieving to obtain high-performance iron-based alloy powder.
[0027] Comparative Example 1: The purpose of this comparative example is to verify the effect of a single phytic acid modified structure on the properties of iron-based alloy powder.
[0028] S1, 15 parts of phytic acid were added to a mixed solvent consisting of 65 parts of ethanol and 95 parts of deionized water, and stirred at 800 r / min for 75 min at 45 °C to obtain a phytic acid modified solution; then 115 parts of iron-based alloy powder were added, and a coating reaction was carried out at 65 °C for 4 h, followed by drying at 100 °C for 8 h, and then pulverizing to obtain phytic acid-modified iron-based alloy powder. S2, 5 parts of 2,7-dihydroxyfluorene, 2.5 parts of graphene, 4 parts of nano-molybdenum disulfide, 3 parts of zinc stearate, 5 parts of polyethylene wax, 1.5 parts of antioxidant and 1 part of leveling agent were added to a mixed solvent and dispersed and mixed at 800 r / min for 50 min at 40 °C to obtain a functional additive dispersion; then, phytic acid-modified iron-based alloy powder was added to the functional additive dispersion and mixed and coated at 58 °C for 3 h. S3. The resulting mixture is dried at 90°C for 6 hours, followed by granulation and 350-mesh sieving to obtain iron-based alloy powder.
[0029] Comparative Example 2: The purpose of this comparative example is to verify the effect of phytic acid-benzimidazole two-component modified structure on the properties of iron-based alloy powder.
[0030] S1, 15 parts of phytic acid and 10 parts of benzimidazole were added to a mixed solvent consisting of 65 parts of ethanol and 95 parts of deionized water, and stirred at 800 r / min for 75 min at 45 °C to obtain a coordination modified solution; then 115 parts of iron-based alloy powder were added, and a coating reaction was carried out at 65 °C for 4 h, followed by drying at 100 °C for 8 h, and then pulverizing to obtain phytic acid-benzimidazole modified iron-based alloy powder. S2, 5 parts of 2,7-dihydroxyfluorene, 2.5 parts of graphene, 4 parts of nano-molybdenum disulfide, 3 parts of zinc stearate, 5 parts of polyethylene wax, 1.5 parts of antioxidant and 1 part of leveling agent were added to a mixed solvent and dispersed and mixed at 800 r / min for 50 min at 40 °C to obtain a functional additive dispersion; then, phytic acid-benzimidazole modified iron-based alloy powder was added to the functional additive dispersion and mixed and coated at 58 °C for 3 h. S3. The resulting mixture is dried at 90°C for 6 hours, followed by granulation and 350-mesh sieving to obtain iron-based alloy powder.
[0031] Comparative Example 3: The purpose of this comparative example is to verify the effect of 2,7-dihydroxyfluorene organic electronically modulated small molecules on the properties of iron-based alloy powder.
[0032] S1, 15 parts of phytic acid and 10 parts of benzimidazole were added to a mixed solvent consisting of 65 parts of ethanol and 95 parts of deionized water, and the mixture was stirred at 800 r / min for 75 min at 45 °C to obtain a coordination precursor solution; then 15 parts of tetrabutyl titanate were added at a dropping rate of 1 mL / min, and a hydrolysis-condensation reaction was carried out at 58 °C for 3 h to obtain a phytic acid-benzimidazole-titanium oxide cluster synergistic modification solution; then 115 parts of iron-based alloy powder were added, and a coating reaction was carried out at 65 °C for 4 h, followed by drying at 100 °C for 8 h and pulverization to obtain phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder. S2, 2.5 parts graphene, 4 parts nano molybdenum disulfide, 3 parts zinc stearate, 5 parts polyethylene wax, 1.5 parts antioxidant and 1 part leveling agent were added to a mixed solvent and dispersed and mixed at 800 r / min for 50 min at 40℃ to obtain a functional additive dispersion; then phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder was added to the functional additive dispersion and mixed and coated at 58℃ for 3 h. S3. The resulting mixture is dried at 90°C for 6 hours, followed by granulation and 350-mesh sieving to obtain iron-based alloy powder.
[0033] Performance testing: 1. Powder flowability test The high-performance iron-based alloy powders obtained in the examples and comparative examples were dried in a vacuum drying oven at 80℃ for 2 hours and then cooled to room temperature for later use. Subsequently, according to the test method of GB / T 1482, 50g of powder was weighed and added to a standard funnel of a Hall flow meter. Timing was started from the moment the funnel baffle was opened, and the time required for the powder to flow out completely was recorded. Each group of samples was tested in parallel three times and the average value was taken. At the same time, it was observed whether the powder would cause clogging, bridging and obvious agglomeration during the flow process. The dispersion performance and processing flow performance of the powder were evaluated by the powder flow time and flow stability. The shorter the flow time and the absence of obvious clogging, the better the powder flow performance.
[0034] 2. Sintering densification performance test The high-performance iron-based alloy powders obtained in the examples and comparative examples were added into molds and pressed into standard rectangular samples with dimensions of 30 mm × 10 mm × 5 mm under a pressure of 600 MPa. The samples were then placed in an argon-protected atmosphere sintering furnace and heated to 1180 °C at a heating rate of 10 °C / min and held at that temperature for 2 h. The samples were then cooled to room temperature with the furnace. The bulk density and open porosity of the sintered samples were determined using the Archimedes displacement method, and the presence of obvious cracks, collapses, and pore defects on the sample surface was observed to evaluate the sintering densification performance and particle interface bonding ability of the iron-based alloy powder.
[0035] 3. Wear resistance test The high-performance iron-based alloy powder obtained in the examples and comparative examples was sintered and molded into test samples with dimensions of 20mm×20mm×5mm, and the test surface was polished. Then, a dry friction test was carried out using a friction and wear testing machine. The friction pair was GCr15 steel balls, the load was 20N, the rotation speed was 300r / min, the friction radius was 5mm, and the continuous friction time was 30min. After the test, the mass change of the sample before and after wear was measured using an electronic balance, and the wear mark width and surface peeling were observed. The wear resistance and interfacial stability of the material were evaluated by the wear weight loss and wear mark state.
[0036] 4. High-temperature antioxidant performance test 10g of the high-performance iron-based alloy powder obtained in the examples and comparative examples were weighed and evenly spread in an alumina crucible. Then, the crucible was placed in a muffle furnace and heated to 800℃ at a heating rate of 8℃ / min under an air atmosphere and held for 4h. After the sample cooled naturally to room temperature, the mass change of the powder before and after oxidation was measured, and the color change, surface sintering and agglomeration were observed. The high-temperature oxidation resistance of the high-performance iron-based alloy powder was evaluated by the weight gain per unit mass of oxidation and the surface condition of the powder.
[0037] Table 1 Performance test results of the examples and comparative examples
[0038] According to Table 1, the high-performance iron-based alloy powders obtained in Examples 1-3 are significantly better than those in Comparative Examples 1-3 in terms of powder flow properties, sintering densification properties, wear resistance properties, and high-temperature oxidation resistance properties. This indicates that the phytic acid-benzimidazole-titanium oxide cluster synergistic confined modification structure and 2,7-dihydroxyfluorene can produce a significant synergistic effect, thereby effectively improving the comprehensive performance of the iron-based alloy powder.
[0039] In Example 2, the Hall flow rate was 14.2 s / 50 g, which was significantly lower than that of Comparative Example 1 (24.8 s / 50 g) and Comparative Example 2 (21.3 s / 50 g). This indicates that the synergistic confinement structure formed by phytic acid, benzimidazole, and titanium oxide clusters can effectively reduce the agglomeration phenomenon on the surface of iron-based alloy powder and improve the uniformity and dispersion performance of the particle surface. At the same time, the introduction of 2,7-dihydroxyfluorene further improved the interfacial energy state of the particles, thereby enhancing the flow stability of the powder. Therefore, Example 2 exhibited the best flow performance.
[0040] Regarding sintering densification performance, Example 2 achieved a sintering density of 7.43 g / cm³ and a porosity of only 2.9%, both superior to Examples 1, 3, and the comparative examples. This indicates that the polyphosphate groups in phytic acid, after forming a stable coordination structure with the iron-based particle surface, can enhance the interfacial bonding ability of the particles; the nitrogen-containing aromatic heterocyclic structure in benzimidazole can promote interfacial wetting and electron migration during the sintering process; and the inorganic confined network formed by the titanium oxide clusters can improve the diffusion stability between particles, thus significantly improving the sintering densification effect. In contrast, Comparative Examples 1 and 2, lacking a complete synergistic confined structure, showed significantly lower sintering densities and significantly higher porosities.
[0041] In the wear resistance test, the wear loss of Example 2 was only 9.6 mg, which was significantly lower than 27.5 mg of Comparative Example 1 and 22.8 mg of Comparative Example 2. This indicates that the complete synergistic confined structure can effectively enhance the interparticle bonding strength and improve the density of the sintered structure, thereby reducing the material surface spalling phenomenon during friction. In addition, the rigid aromatic ring structure of 2,7-dihydroxyfluorene can further improve the interfacial stability. Therefore, Example 2 exhibits superior wear resistance.
[0042] Regarding high-temperature antioxidant performance, the oxidation weight gain of Example 2 was only 6.8 mg / g, which was significantly lower than that of the comparative examples. This indicates that the coordination adsorption layer formed by phytic acid and the inorganic confinement structure formed by titanium oxide clusters can effectively inhibit the diffusion of oxygen to the surface of iron-based particles under high-temperature conditions, thereby reducing the oxidation rate of the powder. Although Comparative Example 3 has a synergistic confinement structure, its antioxidant performance is still lower than that of Example 2 due to the lack of the regulatory effect of 2,7-dihydroxyfluorene on the electronic structure of the interface.
[0043] In summary, this invention, through the synergistic confinement structure of phytic acid-benzimidazole-titanium oxide cluster and the synergistic effect of 2,7-dihydroxyfluorene, can significantly improve the flow properties, sintering densification properties, wear resistance and high-temperature oxidation resistance of iron-based alloy powders. Among them, Example 2 showed the best comprehensive performance under medium component content and medium reaction conditions, indicating that the system has good synergistic effect and practical application value.
Claims
1. A high-performance iron-based alloy powder, characterized in that, The raw materials include the following parts by weight: 80-150 parts of phytic acid-benzimidazole-titanium oxide cluster synergistic confined modification iron-based alloy powder; 1-10 parts of 2,7-dihydroxyfluorene; 0.5-5 parts of graphene; 1-6 parts of zinc stearate; 2-8 parts of polyethylene wax; 1-8 parts of nano-molybdenum disulfide; 0.5-3 parts of antioxidant; and 0.3-2 parts of leveling agent. The phytic acid-benzimidazole-titanium oxide cluster synergistic confined modification iron-based alloy powder is formed by synergistic modification of the iron-based alloy powder surface by coordination deposition and confined coating of phytic acid and benzimidazole under the action of titanium oxide cluster precursor. The iron-based alloy powder is a Fe-Cr-Ni-V pre-alloy powder, and the mass ratio of Fe, Cr, Ni and V in the Fe-Cr-Ni-V pre-alloy powder is (68-84):(10-20):(3-10):(0.2-2).
2. The high-performance iron-based alloy powder according to claim 1, characterized in that, The phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder comprises the following raw materials in parts by weight: 80-150 parts iron-based alloy powder; 5-25 parts phytic acid; 3-20 parts benzimidazole; 5-25 parts tetrabutyl titanate; 30-100 parts ethanol; and 40-150 parts deionized water.
3. A high-performance iron-based alloy powder according to claim 1 or 2, characterized in that, The preparation method of the phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder includes the following steps: (1) Phytic acid and benzimidazole were added to a mixed solvent to carry out a mixed reaction to obtain a coordination precursor solution; (2) Add tetrabutyl titanate to the coordination precursor solution to carry out hydrolysis and condensation reaction to obtain phytic acid-benzimidazole-titanium oxide cluster synergistic modified solution; (3) The iron-based alloy powder is added to the phytic acid-benzimidazole-titanium oxide cluster synergistic modification liquid for coating modification, and then filtered, dried and pulverized to obtain the phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder.
4. The high-performance iron-based alloy powder according to claim 3, characterized in that, In step (1), phytic acid and benzimidazole are stirred and reacted at 30-60°C for 30-120 min.
5. The high-performance iron-based alloy powder according to claim 3, characterized in that, In step (2), the dropping rate of tetrabutyl titanate is 0.5-2 mL / min, the hydrolysis condensation reaction temperature is 40-75℃, and the reaction time is 1-5 h.
6. The high-performance iron-based alloy powder according to claim 3, characterized in that, In step (3), the iron-based alloy powder and the phytic acid-benzimidazole-titanium oxide cluster synergistic modification liquid are coated and reacted at 50-80℃ for 2-6 hours, and then dried at 80-120℃ for 4-12 hours.
7. The high-performance iron-based alloy powder according to claim 1, characterized in that, The antioxidant is formed by mixing antioxidant 1010 and antioxidant 168 in a mass ratio of (1-3):1; the leveling agent is formed by mixing polyether modified polysiloxane and polyacrylate leveling agent in a mass ratio of 1:(1-4).
8. A method for preparing high-performance iron-based alloy powder, characterized in that, The preparation method includes the following steps: S1, 2,7-dihydroxyfluorene, graphene, nano-molybdenum disulfide, zinc stearate, polyethylene wax, antioxidant and leveling agent are added to a mixed solvent for dispersion to obtain a functional additive dispersion; S2, phytic acid-benzimidazole-titanium oxide cluster synergistic confinement modified iron-based alloy powder is added to the dispersion of the functional additive for mixing and coating treatment; S3 involves drying, granulating, and sieving the mixture to obtain high-performance iron-based alloy powder.
9. The method for preparing a high-performance iron-based alloy powder according to claim 8, characterized in that, In S1, the dispersion mixing speed is 400-1200 r / min, the dispersion temperature is 25-60℃, and the dispersion time is 20-90 min; in S2, the phytic acid-benzimidazole-titanium oxide cluster synergistic confined modified iron-based alloy powder and functional additive dispersion are mixed and coated at 40-75℃ for 1-5 h.
10. The method for preparing a high-performance iron-based alloy powder according to claim 8, characterized in that, The drying temperature in S3 is 70-110℃, the drying time is 3-10h, and the sieve mesh size is 200-500 mesh.