Preparation method of high-hardness wear-resistant aluminum bronze alloy

Abstract

The application discloses a preparation method of high-hardness wear-resistant aluminum bronze alloy and belongs to the technical field of metal materials. The method is characterized by accurately controlling the content of aluminum to be 8.5-10.5%, the content of iron to be 3.0-5.0%, the content of nickel to be 2.0-4.0%, the content of manganese to be 0.8-1.5%, the content of silicon to be 0.1-0.4%, the content of titanium to be 0.05-0.20% and the content of zirconium to be 0.03-0.15%, and combining magnetic field assisted directional solidification and multi-stage heat treatment to realize the synergistic strengthening of beta prime martensite and fine dispersed phase in a single matrix. The obtained alloy has a Vickers hardness of greater than or equal to 320HV, a wear rate of less than or equal to 2.5*10 6 mm³ / (N*m), an elongation rate of greater than or equal to 8%, high hardness, high wear resistance and good plasticity and toughness. The application aims at solving the problems of insufficient reliability, uneven structure and industrialization difficulty caused by the dependence on surface coating or the introduction of endogenous hard phase in the prior art.

Description

Technical Field

[0001] This invention relates to the field of metal materials technology, and in particular to a method for preparing a high-hardness, wear-resistant aluminum bronze alloy. Background Technology

[0002] In high-end equipment, marine engineering, and the automotive industry, critical friction components often operate under extreme conditions such as high loads, strong corrosion, and dry friction, placing extremely high demands on material properties. Aluminum bronze alloys, due to their excellent corrosion resistance, thermal conductivity, and high strength-ductility ratio, are widely used in core components such as bearings, bushings, and gears. However, as equipment develops towards lightweighting, high power density, and long service life, traditional aluminum bronze struggles to meet the dual requirements of high overall hardness and high wear resistance. Therefore, developing a method for preparing high-hardness, wear-resistant aluminum bronze that can achieve a uniform and dispersed distribution of reinforcing phases within the matrix has become a key technological path for the advancement of materials.

[0003] Existing technologies mainly revolve around two routes: one is surface composite strengthening, such as preparing wear-resistant coatings on aluminum bronze surfaces through laser cladding. Although this method can improve surface performance, the coating is prone to peeling, and the process is complex and has poor stability; the other is adding a hard second phase, such as introducing ceramic particles to reinforce the matrix. This route is cumbersome, prone to introducing inclusions and pores, damaging the uniformity of the microstructure, and fails to systematically optimize the alloy composition and precipitate control.

[0004] In summary, current technology faces inherent contradictions: surface coatings sacrifice overall reliability, while endogenous reinforcement is constrained by process and microstructure uniformity. Existing methods have failed to achieve uniform and dispersed precipitation of high-hardness reinforcing phases in aluminum bronze matrices from a synergistic perspective of "composition-process-microstructure-performance." Therefore, how to achieve fine, dispersed reinforcing phases in aluminum bronze matrices through compositional design and process optimization without surface modification or introducing external defects, thereby obtaining high-performance materials with high hardness, high wear resistance, good ductility and toughness, and microstructure stability, remains a pressing technical challenge that needs to be overcome. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing a high-hardness, wear-resistant aluminum bronze alloy, so as to solve the technical problems in the prior art that the reliance on surface coating leads to insufficient service reliability or that the introduction of inclusions and uneven microstructure by endogenous hard phases makes it difficult to achieve both high hardness, high wear resistance and industrial feasibility.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: This invention achieves simultaneous synthesis of β' martensite phase and micro-alloying phase in a single homogeneous matrix by precisely controlling the ratio of main alloying elements to micro-alloying elements, combined with directional solidification control and a multi-stage heat treatment process. The fine, dispersed precipitation of the phase results in an aluminum bronze alloy with high overall hardness, high wear resistance, good ductility and toughness, and high structural stability.

[0007] The chemical composition of the high-hardness, wear-resistant aluminum bronze alloy, by mass percentage, is: aluminum 8.5%–10.5%, iron 3.0%–5.0%, nickel 2.0%–4.0%, manganese 0.8%–1.5%, silicon 0.1%–0.4%, titanium 0.05%–0.20%, zirconium 0.03%–0.15%, with the balance being copper and unavoidable impurities. The aluminum content is controlled within the range of 8.5%–10.5% to ensure sufficient formation during subsequent heat treatment. The phase transforms into high-hardness β' martensite after quenching; the synergistic addition of iron and nickel not only promotes The precipitation of the phase is also enhanced by solid solution strengthening. Matrix strength; manganese is used to refine grains and suppress high-temperature stress. Phase coarsening; silicon, as a deoxidizer, improves melt purity, while a trace amount of solid dissolved in the matrix enhances wear resistance; titanium and zirconium, as microalloying elements, have atomic radii that are significantly different from those of the copper matrix, which can form high-density heterogeneous nucleation cores in the early stage of solidification, significantly refine the as-cast structure, and agglomerate at the κ phase interface during aging, inhibiting its coarsening and growth, thereby maintaining the dispersed distribution of the strengthening phase.

[0008] The preparation method of the present invention includes the following steps: Step 1: Weigh and mix electrolytic copper, pure aluminum, pure iron, electrolytic nickel, metallic manganese, industrial silicon, titanium ingots, and zirconium blocks according to the mass percentage, wherein the aluminum content is 8.5%–10.5%, the iron content is 3.0%–5.0%, the nickel content is 2.0%–4.0%, the manganese content is 0.8%–1.5%, the silicon content is 0.1%–0.4%, the titanium content is 0.05%–0.20%, the zirconium content is 0.03%–0.15%, and the balance is copper and unavoidable impurities; Step 2: Place the raw material in a vacuum induction melting furnace, heat it to 1250℃~1300℃ under an argon protective atmosphere, and hold it at that temperature for 30 minutes to obtain a homogeneous melt; Step 3: Pour the melt into a metal mold preheated to 600°C. The bottom of the mold is equipped with a water-cooled copper plate and a 0.8 Tesla axial steady magnetic field is applied to make the solidification front flow in a directional manner under the action of Lorentz force, so as to obtain an ingot with dense structure and uniform composition. Step 4: Place the ingot under a vacuum of not less than 10... -2 Homogenization annealing was carried out at 550℃ for 4 hours under Pa conditions. Step 5: Then heat to 920℃ and hold for 2 hours for solution treatment, and immediately quench in water to room temperature to transform the high-temperature β phase into supersaturated β' martensite; Step 6: Perform time-sensitive processing to expedite the process. Follow Uniform precipitation at the interface between the matrix and β' martensite, resulting in The average particle size of the phase is 80 nm to 150 nm, and the volume fraction is not less than 18%.

[0009] Furthermore, in step 3, the inner surface of the metal mold cavity is coated with a 0.3 mm thick yttrium oxide-zirconia composite ceramic coating. This coating is made by mixing 70% yttrium oxide and 30% zirconia in a mass ratio and then preparing a slurry with water glass binder before spraying. After drying at 200°C, a dense isolation layer is formed, which effectively prevents the melt from reacting with the mold and reduces surface oxidation. In step 3, the axial steady magnetic field is generated by a superconducting magnet. The direction of the magnetic field is parallel to the direction of gravity, and the magnetic field strength remains constant in the solidification region to ensure that the melt convection mode is stable and controllable. In step 5, the water quenching medium is deionized water, the temperature is controlled at 25°C ± 2°C, and the quenching transfer time does not exceed 3 seconds to avoid the non-martensitic transformation of the β phase during the cooling process.

[0010] In a preferred embodiment of the present invention, the addition ratio of titanium and zirconium in step 1 satisfies a Ti / Zr atomic ratio of 1.2 to 2.0. This ratio range allows the two elements to form (Ti,Zr)C or (Ti,Zr)N composite precipitates in the early stage of solidification, serving as efficient heterogeneous nucleation nuclei, significantly reducing nucleation undercooling, and refining the as-cast grain size to below 50 micrometers. Simultaneously, during the aging process, titanium and zirconium atoms along... Phase / matrix interface segregation forms a solute dragging layer approximately 2 nanometers wide, effectively hindering... The Ostwald ripening of the phase maintains its diffuse distribution state.

[0011] In step 6 The phase is an iron-nickel-rich intermetallic compound with a body-centered cubic or complex cubic crystal structure, and its main components are... or The phase is Uniform precipitation at the interface between the copper matrix and β' martensite maintains a coherent or semi-coherent interface relationship with the matrix, providing a significant second-phase strengthening effect. The β' martensite has an ordered body-centered cubic structure, exhibiting high hardness and a certain degree of brittleness, but is weakened by fine crystals. The phase is divided into a micro-network, which effectively blocks the crack propagation path, thereby improving the hardness while maintaining the overall toughness of the material.

[0012] The preparation method described in this invention does not introduce any exogenous ceramic particles or oxide precursors, avoiding the generation of non-metallic inclusions and porosity defects, and ensuring that the density of the as-cast microstructure is not less than 99.5%. Simultaneously, through the synergistic design of composition, solidification, and heat treatment, the type, size, distribution, and volume fraction of the strengthening phase are all within the optimal range, ultimately obtaining a Vickers hardness of not less than... The wear rate under dry friction conditions is no higher than The overall performance index is an elongation rate of not less than 8%.

[0013] Furthermore, the homogenization annealing is performed at a vacuum degree not lower than The process is carried out in an environment that prevents the oxidation and loss of active elements such as aluminum and manganese at high temperatures; the solution treatment temperature is strictly controlled at 920℃, which is within the range of... The upper limit of the two-phase region ensures that the β phase fully dissolves elements such as iron and nickel to form a homogeneous solid solution, while avoiding excessive grain growth; the aging temperature of 480℃ is... The optimal window for phase precipitation kinetics and thermodynamic equilibrium; below this temperature, precipitation is insufficient; above this temperature, precipitation... Accelerated phase coarsening leads to a decrease in the strengthening effect.

[0014] The high-hardness wear-resistant aluminum bronze alloy is suitable for manufacturing friction pair components such as bearings, bushings, gears, sealing rings, and propellers. Its overall performance is uniform, with no performance gradient between the surface and the core. Even if the surface layer experiences slight wear during service, the subsurface layer still has the same high hardness and wear resistance, significantly extending the service life of the components.

[0015] Compared with the prior art, the beneficial technical effects of the present invention are as follows: The preparation method of this invention does not introduce any exogenous ceramic particles or oxide precursors, avoiding the generation of non-metallic inclusions and porosity defects, and ensuring that the density of the as-cast microstructure is not less than 99.5%. Simultaneously, through the synergistic design of composition, solidification, and heat treatment, the type, size, distribution, and volume fraction of the strengthening phase are all within the optimal range, ultimately achieving a Vickers hardness of not less than 320 HV and a wear rate under dry friction conditions not exceeding 2.5 × 10⁻⁶. -6 mm 3 The comprehensive performance indicators include N·m and elongation of not less than 8%.

[0016] The high-hardness wear-resistant aluminum bronze alloy described in this invention is suitable for manufacturing friction pair components such as bearings, bushings, gears, sealing rings, and propellers. Its overall performance is uniform, with no performance gradient between the surface and the core. Even if the surface layer experiences slight wear during service, the subsurface layer still possesses the same high hardness and wear resistance, significantly extending the service life of the components.

[0017] The technical solution of this invention, through systematic integration of composition design, directional solidification control, and multi-stage heat treatment, achieves for the first time the synthesis of β' martensite and... The phase synergistic strengthening mechanism breaks through the dual dilemma of "surface strengthening sacrificing integrity" and "endogenous strengthening introducing defects" in the traditional technical path, and provides a new paradigm that can be industrially implemented for high-performance copper alloys for high-end equipment.

[0018] This invention achieves a uniform and dispersed distribution of high-hardness reinforcing phases in an aluminum bronze alloy matrix by precisely controlling the alloy composition, applying a magnetic field to assist directional solidification, and optimizing a multi-stage heat treatment process, without introducing foreign phases or relying on surface modification. This significantly improves the overall hardness, wear resistance, and service reliability of the material, demonstrating outstanding substantive features and remarkable progress. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the preparation process of the high-hardness wear-resistant aluminum bronze alloy of the present invention; Figure 2 This is a schematic diagram of a typical microstructure of the aluminum bronze alloy obtained in an embodiment of the present invention. Detailed Implementation

[0020] The features and exemplary embodiments of various aspects of the present invention will now be described in detail. To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely intended to explain the present invention and not to limit the present invention. For those skilled in the art, the present invention can be practiced without some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present invention by illustrating examples of the invention.

[0021] This invention relates to a method for preparing a high-hardness, wear-resistant aluminum bronze alloy. The core of this method lies in achieving simultaneous synthesis of the β' martensite phase and... (The sentence is incomplete and requires more context to translate accurately.) The fine, dispersed precipitation of the phase results in an aluminum bronze alloy that combines high hardness, high wear resistance, good ductility and toughness, and high structural stability. See also... Figure 1 , Figure 1 This is a schematic diagram of the preparation process of the high-hardness, wear-resistant aluminum bronze alloy of the present invention. The technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0022] See Figure 2 , Figure 2This is a schematic diagram of a typical microstructure of the aluminum bronze alloy obtained in an embodiment of the present invention. The chemical composition of the high-hardness, wear-resistant aluminum bronze alloy, by mass percentage, is: aluminum 8.5%–10.5%, iron 3.0%–5.0%, nickel 2.0%–4.0%, manganese 0.8%–1.5%, silicon 0.1%–0.4%, titanium 0.05%–0.20%, zirconium 0.03%–0.15%, with the balance being copper and unavoidable impurities. Aluminum, as the main alloying element, is included within a specific content range to ensure sufficient high-temperature formation during subsequent heat treatment. The phase transforms into ordered body-centered cubic β' martensite after quenching; iron and nickel work synergistically to promote the formation of iron-nickel-rich intermetallic compounds. On the one hand, the precipitation of the phase is enhanced by solid solution strengthening. The strength of the copper matrix; manganese is used to refine the grains and suppress high-temperature stress. Phase coarsening; silicon acts as a deoxidizer to improve melt purity, while trace amounts dissolve in the matrix to enhance wear resistance; titanium and zirconium, as microalloying elements, have atomic radii significantly different from the copper matrix, forming high-density heterogeneous nucleation sites in the early stages of solidification, significantly refining the as-cast microstructure, and segregating during aging. Phase / matrix interface, suppression phase Mature to maintain its diffuse distribution.

[0023] Furthermore, the ratio of titanium to zirconium added meets the requirements. The atomic ratio is 1.2 to 2.0. Within this range, the two elements can form [a specific structure / form] in the early stages of solidification. The composite precipitate, acting as a highly efficient heterogeneous nucleation core, significantly reduces nucleation undercooling, refining the as-cast grain size to below 50 micrometers; simultaneously, during the aging process, titanium and zirconium atoms along... Phase / matrix interface segregation forms a solute dragging layer approximately 2 nanometers wide, effectively hindering... The coarsening and growth of the phase maintains the diffuse distribution of the strengthening phase.

[0024] The preparation method of this invention includes the following steps: Step 1: Weigh and mix electrolytic copper, pure aluminum, pure iron, electrolytic nickel, metallic manganese, industrial silicon, titanium ingots, and zirconium blocks according to the mass percentage, wherein the aluminum content is 8.5%–10.5%, the iron content is 3.0%–5.0%, the nickel content is 2.0%–4.0%, the manganese content is 0.8%–1.5%, the silicon content is 0.1%–0.4%, the titanium content is 0.05%–0.20%, the zirconium content is 0.03%–0.15%, and the balance is copper and unavoidable impurities; Step 2: Place the above raw materials in a vacuum induction melting furnace, heat to 1250℃~1300℃ under an argon protective atmosphere and hold for 30 minutes to obtain a homogeneous melt; Step 3: Pour the melt into a metal mold preheated to 600°C. The bottom of the mold is equipped with a water-cooled copper plate and a 0.8 Tesla axial steady magnetic field is applied to make the solidification front flow in a directional manner under the action of Lorentz force, so as to obtain an ingot with dense structure and uniform composition. Step 4: Place the ingot under a vacuum of not less than 10 -2 Homogenization annealing was carried out at 550℃ for 4 hours under Pa conditions. Step 5: Then heat to 920℃ and hold for 2 hours for solution treatment, and immediately quench in water to room temperature to transform the high-temperature β phase into supersaturated β' martensite; Step 6: Perform aging treatment by holding at 480℃ for 6 hours to promote aging. Follow Uniform precipitation at the interface between the matrix and β' martensite, resulting in The average particle size of the phase is 80 nm to 150 nm, and the volume fraction is not less than 18%.

[0025] In a preferred embodiment of the present invention, in step 3, the inner surface of the metal mold cavity is coated with a 0.3 mm thick yttrium oxide-zirconia composite ceramic coating. This coating is prepared by mixing 70% yttrium oxide and 30% zirconia in a mass ratio, then mixing with water glass binder to form a slurry, which is then sprayed onto the surface. After drying at 200°C, a dense isolation layer is formed, effectively preventing the melt from reacting with the mold and reducing surface oxidation. In step 3, the axial steady magnetic field is generated by a superconducting magnet, with the magnetic field direction parallel to the direction of gravity. The magnetic field strength remains constant in the solidification region, ensuring a stable and controllable melt convection mode. In step 5, the water quenching medium is deionized water, the temperature is controlled at 25°C ± 2°C, and the quenching transfer time does not exceed 3 seconds to avoid… The phase undergoes a non-martensitic transformation during cooling.

[0026] The homogenization annealing in step 4 is carried out under a vacuum degree of not less than 10. -2 The solution treatment is carried out in a Pa environment to prevent the oxidation and loss of active elements such as aluminum and manganese at high temperatures. The solution treatment temperature is strictly controlled at 920℃, which is within the range of... The upper limit of the two-phase region ensures that the β phase fully dissolves elements such as iron and nickel to form a homogeneous solid solution, while avoiding excessive grain growth. The aging temperature is 480℃. The optimal window for phase precipitation kinetics and thermodynamic equilibrium; below this temperature, precipitation is insufficient; above this temperature, precipitation... Accelerated phase coarsening leads to a decrease in the strengthening effect.

[0027] Step 6 The phase is an iron-nickel-rich intermetallic compound with a body-centered cubic or complex cubic crystal structure, and its main components are... or The phase is Uniform precipitation at the interface between the copper matrix and β' martensite, maintaining a coherent or semi-coherent interface relationship with the matrix, provides a significant second-phase strengthening effect. β' martensite has an ordered body-centered cubic structure, exhibiting high hardness and a degree of brittleness, but due to its finely dispersed structure... The phase is divided into a micro-network, which effectively blocks the crack propagation path, thereby improving the hardness while maintaining the overall toughness of the material.

[0028] The preparation method of this invention does not introduce any exogenous ceramic particles or oxide precursors, avoiding the generation of non-metallic inclusions and porosity defects, and ensuring that the density of the as-cast microstructure is not less than 99.5%. Simultaneously, through the synergistic design of composition, solidification, and heat treatment, the type, size, distribution, and volume fraction of the strengthening phase are all within the optimal range, ultimately achieving a Vickers hardness of not less than 320 HV and a wear rate under dry friction conditions not exceeding 2.5 × 10⁻⁶. -6 mm 3 The comprehensive performance indicators include N·m and elongation of not less than 8%.

[0029] Example 1: Electrolytic copper 83.2%, pure aluminum 9.8%, pure iron 4.2%, electrolytic nickel 2.8%, metallic manganese 1.2%, industrial silicon 0.25%, titanium ingot 0.12%, zirconium block 0.08% were weighed by mass percentage, with the balance being unavoidable impurities. The raw materials were loaded into a vacuum induction melting furnace and melted at 1280℃ for 30 minutes under argon protection. The melt was then poured into a metal mold preheated to 600℃. A water-cooled copper plate was placed at the bottom of the mold, and a 0.8 Tesla axial constant magnetic field was applied. The ingot was subjected to vacuum homogenization annealing at 550℃ for 4 hours, followed by solution treatment at 920℃ for 2 hours, water quenching to room temperature, and then aging treatment at 480℃ for 6 hours. The resulting alloy microstructure consisted of… Matrix, β' martensite and diffusely distributed Phase composition, The phase average particle size is 110 nm, the volume fraction is 19.3%, and the Vickers hardness is... Dry friction wear rate 2.1×10 -6 mm 3 / (N·m), elongation 8.7%.

[0030] Example 2: The following components were weighed by mass percentage: 82.5% electrolytic copper, 10.2% pure aluminum, 4.8% pure iron, 3.5% electrolytic nickel, 1.4% metallic manganese, 0.32% industrial silicon, 0.15% titanium ingot, and 0.10% zirconium block, with the balance being unavoidable impurities. The melting temperature was 1290℃, and the casting conditions were the same as in Example 1. Homogenization annealing was performed at 550℃ for 4 hours, solution treatment at 920℃ for 2 hours, water quenching, and aging at 480℃ for 6 hours. In the alloy… The phase average particle size is 130 nm, the volume fraction is 20.1%, the Vickers hardness is 335 HV, and the wear rate is... The elongation rate is 8.2%.

[0031] Example 3: Electrolytic copper 84.0%, pure aluminum 9.0%, pure iron 3.5%, electrolytic nickel 2.2%, metallic manganese 0.9%, industrial silicon 0.18%, titanium ingot 0.09%, and zirconium block 0.06% were weighed by mass percentage, with the balance being unavoidable impurities. The melting temperature was 1260℃, and the remaining processes were the same as in Example 1. The resulting alloy... The phase has an average particle size of 95 nm, a volume fraction of 18.5%, a Vickers hardness of 322 HV, and a wear rate of 2.3 × 10⁻⁶. -6 mm 3 / (N·m), elongation 9.1%.

[0032] Example 4: The following components were weighed by weight percentage: 83.6% electrolytic copper, 9.5% pure aluminum, 4.0% pure iron, 3.0% electrolytic nickel, 1.1% metallic manganese, 0.22% industrial silicon, 0.11% titanium ingot, and 0.07% zirconium block, with the balance being unavoidable impurities. The melting temperature was 1275℃, and the remaining processes were the same as in Example 1. Alloy The phase average particle size is 105 nm, the volume fraction is 19.0%, the Vickers hardness is 330 HV, and the wear rate is 2.0 × 10⁻⁶. -6 mm 3 / (N·m), elongation 8.9%.

[0033] To verify the superiority of the technical solution of the present invention, several comparative examples were set up for comparative analysis.

[0034] Comparative Example 1: Using the method patented in CN120425180B, an aluminum bronze substrate was prepared, followed by magnetic field-assisted laser cladding of a WC-Co coating. The coating thickness was 1.2 mm. After tempering, the surface hardness reached 850 HV, but the substrate hardness was only 180 HV. In dry friction tests, the initial wear rate was low, but after the coating was worn through, the wear rate increased sharply to 8.5 × 10⁻⁶. -6 mm 3 / (N·m), and the overall service life is only 42% of that of the embodiment of the present invention.

[0035] Comparative Example 2: Using the method of patent CN114277278B, chromium trioxide and niobium pentoxide powders were added, followed by ball milling, calcination, copper plating, and then casting. Although the resulting alloy achieved a hardness of 310 HV, metallographic observation revealed numerous 5-20 micrometer oxide inclusions and micropores, with a density of 97.8%. In fatigue tests, cracks initiated at the inclusion sites, and the fatigue limit was 28% lower than that of the embodiment of this invention.

[0036] Comparative Example 3: The alloy composition does not contain titanium or zirconium; the remaining elements are the same as in Example 1. The as-cast grain size reaches 120 micrometers. After aging, the phase has an average particle size of 210 nm, a volume fraction of 16.5%, a hardness of 295 HV, and a wear rate of 3.8 × 10⁻⁶. -6 mm 3 / (N·m), elongation 7.3%. The coarsening of the reinforcing phase leads to a significant decrease in wear resistance.

[0037] Comparative Example 4: Magnetic field-assisted solidification was removed; the remaining processes were the same as in Example 1. The ingot exhibited significant dendritic segregation, with aluminum and iron segregation coefficients reaching 1.35. The phase distribution is uneven, with localized aggregation forming coarse precipitation zones. Hardness fluctuates between 280 and 310 HV, and the standard deviation of the wear rate increases to [missing value]. Poor batch consistency.

[0038] Comparative Example 5: The solution temperature was increased to 950℃, and the rest was the same as in Example 1. The grain size was significantly coarsened to over 150 micrometers. Excessive dissolution of the phase leads to aging The phase precipitation driving force is insufficient, with a volume fraction of only 14.2%, a hardness of 305HV, and wear resistance not meeting expectations.

[0039] Comparative Example 6: The aging temperature was reduced to 420℃, and the rest was the same as in Example 1. The phase precipitation was insufficient, with an average particle size of 60 nm but a volume fraction of only 12.8%. The hardness was 312 HV, but due to the insufficient amount of reinforcing phase, the wear rate was as high as 3.2 × 10⁻⁶. -6 mm 3 / (N·m).

[0040] Comparative Example 7: The aging temperature was increased to 520℃, and the rest was the same as in Example 1. The phase is severely coarsened, with an average particle size of 280 nanometers. Phase transformation and decomposition occur in some areas, the hardness drops to 298 HV, and the wear rate is 4.1 × 10⁻⁶. -6 mm 3 / (N·m), and the plasticity also decreased to 6.5%.

[0041] Comparative Example 8: Homogenization annealing was omitted, and solution treatment was performed directly. As-cast segregation was not eliminated, and the composition remained uneven after solution treatment, especially during aging. The phase is excessively precipitated in the iron-rich region and absent in the iron-poor region, resulting in uneven hardness distribution, with local areas having a hardness below 280HV and overall unstable wear resistance.

[0042] The performance data of the above embodiments and comparative examples are summarized in the table below:

[0043] As can be seen from the above data, this invention achieves [the desired effect] through the synergistic optimization of component design, directional solidification, and heat treatment regime. The fine, dispersed distribution of the phase and the stable formation of β' martensite result in excellent comprehensive mechanical and tribological properties without introducing foreign phases. Of particular note is that all embodiments exhibit highly consistent performance indicators, demonstrating the good repeatability and industrial feasibility of the process described in this invention.

[0044] High-hardness, wear-resistant aluminum bronze alloys are suitable for manufacturing friction components such as bearings, bushings, gears, sealing rings, and propellers. Its overall performance is uniform, with no performance gradient between the surface and core. Even if slight wear occurs on the surface during service, the subsurface layer retains the same high hardness and wear resistance, significantly extending the service life of components.

[0045] In summary, this invention, through systematic integration of composition design, directional solidification control, and multi-stage heat treatment, has for the first time achieved the synthesis of β' martensite and... The synergistic strengthening mechanism of the phases breaks through the dual dilemmas of "surface strengthening sacrificing overall integrity" and "endogenous strengthening introducing defects" in traditional technical approaches, providing a new paradigm for the industrial implementation of high-performance copper alloys for high-end equipment. Those skilled in the art can reproduce the technical effects of this invention without creative effort based on the technical content disclosed in this specification.

[0046] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape, and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a high-hardness, wear-resistant aluminum bronze alloy, characterized in that, Includes the following steps: Step 1: Weigh and mix electrolytic copper, pure aluminum, pure iron, electrolytic nickel, metallic manganese, industrial silicon, titanium ingots, and zirconium blocks according to the mass percentage, wherein the aluminum content is 8.5%–10.5%, the iron content is 3.0%–5.0%, the nickel content is 2.0%–4.0%, the manganese content is 0.8%–1.5%, the silicon content is 0.1%–0.4%, the titanium content is 0.05%–0.20%, the zirconium content is 0.03%–0.15%, and the balance is copper and unavoidable impurities; Step 2: Place the raw material in a vacuum induction melting furnace, heat it to 1250℃~1300℃ under an argon protective atmosphere, and hold it at that temperature for 30 minutes to obtain a homogeneous melt; Step 3: Pour the melt into a metal mold preheated to 600°C. The bottom of the mold is equipped with a water-cooled copper plate and a 0.8 Tesla axial steady magnetic field is applied to make the solidification front flow in a directional manner under the action of Lorentz force, so as to obtain an ingot with dense structure and uniform composition. Step 4: The ingot is subjected to homogenization annealing at 550°C for 4 hours under a vacuum of not less than 10⁻²Pa. Step 5: Then heat to 920℃ and hold for 2 hours for solution treatment, and immediately quench in water to room temperature to transform the high-temperature β phase into supersaturated β' martensite; Step 6: Perform aging treatment by holding at 480℃ for 6 hours to promote aging. Follow Uniform precipitation at the interface between the matrix and β' martensite, resulting in The average particle size of the phase is 80 nm to 150 nm, and the volume fraction is not less than 18%.

2. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, In step 1, the ratio of titanium to zirconium added satisfies the requirement that the atomic ratio of titanium to zirconium is 1.2 to 2.

0.

3. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, In step 3, the inner surface of the metal mold cavity is coated with a yttrium oxide-zirconia composite ceramic coating with a thickness of 0.3 mm. This coating is formed by mixing 70% yttrium oxide and 30% zirconia in a mass ratio, mixing with water glass binder to form a slurry, spraying, and drying at 200°C.

4. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, In step 3, the axial steady magnetic field is generated by a superconducting magnet. The direction of the magnetic field is parallel to the direction of gravity and remains constant in the solidification region.

5. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, In step 5, the water quenching medium is deionized water, the temperature is controlled at 25℃±2℃, and the quenching transfer time does not exceed 3 seconds.

6. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, In step 6 The phase is an iron-nickel-rich intermetallic compound with a body-centered cubic or complex cubic crystal structure, and its main components are... or And with The matrix and β' martensite maintain a coherent or semi-coherent interface relationship.

7. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, In step 6, the β' martensite has an ordered body-centered cubic structure, which is finely and diffusely distributed. The phase is divided into micro-networks.

8. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, The Vickers hardness of the resulting alloy is not less than The wear rate under dry friction conditions is no higher than The elongation rate is not less than 8%.

9. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, The preparation method does not introduce any exogenous ceramic particles or oxide precursors, thus avoiding the generation of non-metallic inclusions and porosity defects, and ensuring that the density of the as-cast microstructure is not less than 99.5%.

10. The method for preparing the high-hardness wear-resistant aluminum bronze alloy according to claim 1, characterized in that, The resulting alloy is suitable for manufacturing bearings, bushings, gears, sealing rings, or propellers. The alloy has uniform overall properties and no performance gradient between the surface and the core.

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