A wear-resistant and corrosion-resistant zrb2 particle reinforced 2-series aluminum alloy and a preparation method and application thereof

Abstract

The application discloses a kind of wear-resistant corrosion-resistant ZrB2 Particulate Reinforced 2 Series Aluminum Alloy and its preparation method and application, belong to metal matrix composite technical field, by 2 Series Aluminum Alloy matrix, 0.01%~0.2wt.% Micron ZrB2 Particle 5~10 μm and 0.2%~1.0wt.% Nano ZrB2 Particle 30~100 nm are formed, and micron and nano particle mass ratio is 1:3~1:6.Nano ZrB2 Particle surface has in-situ constructed 5~8nm thick Al3Zr transition layer, forms the core-shell structure matched with matrix coherent. Its preparation is realized by adding trace nano Zr powder high-energy ball milling pre-attachment, combined with ultrasonic-electromagnetic coupling field in aluminum melt and 5~15 minutes short-term dynamic limited reaction.This application utilizes double-scale synergy and interface precision customization, breaks the technical bottleneck that corrosion resistance and wear resistance are difficult to consider, greatly improves comprehensive performance.

Description

Technical Field

[0001] This invention belongs to the field of metal matrix composite technology, specifically relating to a wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy, its preparation method and application, and particularly to an aluminum matrix composite material that utilizes micron and nano ZrB2 particles to synergistically enhance wear resistance and corrosion resistance. Background Technology

[0002] Al-Cu series aluminum alloys possess advantages such as high strength, low density, and high specific modulus, making them widely used in aerospace, defense, and civilian industries. However, a significant difference in electrode potential exists between the copper-rich phases (Al₂Cu) and the copper-poor α-Al solid solution in Al-Cu alloys, making them prone to microgalvanic corrosion in Cl⁻ ion environments, leading to a significant deterioration in the material's corrosion resistance. Furthermore, traditional Al-Cu alloys also face challenges from abrasive wear and delamination wear under high humidity, high salt spray, and complex operating conditions. Therefore, simultaneously improving the wear resistance and corrosion resistance of Al-Cu alloys has been a long-standing technical challenge in this field.

[0003] Adding ceramic particles to aluminum alloys is an important way to improve their mechanical properties and corrosion resistance. Among many ceramic reinforcements, ZrB2 has advantages such as high melting point, high hardness, high modulus, good corrosion resistance and wear resistance, and good wettability with aluminum melt, making it an ideal reinforcement for aluminum matrix composites.

[0004] In the existing technology, ZrB2 particle-reinforced aluminum matrix composites are mainly prepared in two ways: one is to generate ZrB2 particles by in-situ reaction of potassium fluoroborate (KBF4) and potassium fluorozirconate (K2ZrF6) in aluminum melt; the other is to add ZrB2 particles externally to aluminum melt.

[0005] The existing technology has the following main defects and shortcomings: (1) The distribution of ZrB2 and Al3Zr generated by the in-situ reaction method is random, lacking active control over the spatial topology of the reinforcing phase. Existing technology CN112708804B discloses the in-situ generation of ZrB2 particles by adding potassium fluoroborate and potassium fluorozirconate to aluminum alloy melt, while existing technology US20190010580A1 further discloses the formation of nano-ZrB2 ceramic reinforcements distributed in aluminum crystals and grain boundaries through an in-situ reaction of Zr and B in aluminum melt. However, in the above in-situ reaction systems, ZrB2 and Al3Zr are parallel reinforcing phases generated simultaneously and randomly in the melt. Al3Zr may nucleate independently or randomly attach to the surface of ZrB2 particles, lacking active design over the spatial topology of the reinforcing phase. For details, please refer to "In-situ Preparation of (ZrB2+Al3Zr)_p / 2124 Composite Material and Its Wear Properties" (Functional Materials, 2013, No. 7). This study also used the Al-Zr-B melt direct reaction method to generate ZrB2+Al3Zr binary particle reinforced composite material in situ. The published data shows that this method can obtain two reinforcing phases, ZrB2 and Al3Zr, but it did not actively design the spatial arrangement relationship between ZrB2 and Al3Zr. Since Al3Zr has a low lattice mismatch with the Al matrix, if it can be oriented and constructed on the surface of ZrB2 particles to form a core-shell structure, it is expected to further improve the interfacial bonding strength and inhibit the excessive growth of Al3Zr. However, current technology has not yet achieved this goal.

[0006] (2) The concept of dual-scale particle reinforcement has been generalized in existing technologies, but there is insufficient optimization of specific proportions for ZrB2 in 2-series aluminum alloys that balance wear resistance and corrosion resistance. The concept of "dual-scale particle hybrid reinforcement" is already quite common in the field of aluminum matrix composites. For example, some studies have used dual-scale SiC particles to reinforce aluminum matrix composites (see "Preparation and Performance Study of Dual-Scale Hybrid Particle Reinforced Aluminum Matrix Composites"), while others have disclosed cross-scale core-shell structure aluminum matrix composites (see "Cross-Scale Core-Shell Structure Aluminum Matrix Composites and Preparation Methods"). Other studies have used a combination of external addition of micron-sized TiC particles and in-situ synthesis of nano-sized TiC particles to prepare dual-scale TiC reinforced aluminum matrix composites. However, existing dual-scale reinforcement technologies mainly focus on improving mechanical properties (tensile strength, hardness), with insufficient attention paid to the synergistic optimization of corrosion resistance and wear resistance of 2-series aluminum alloys under the coupled effects of corrosive and wear environments. In particular, there is a lack of systematic research in existing technologies on how the mass ratio of micron-sized particles to nano-sized particles simultaneously affects the corrosion resistance and wear resistance of materials.

[0007] (3) When nano-ZrB2 particles are added, the interfacial stability between the ceramic phase and the aluminum matrix is ​​insufficient. Although the added ZrB2 particles have good thermodynamic stability in the aluminum melt, their interfacial bonding with the aluminum matrix mainly relies on physical adsorption and mechanical intercalation, lacking a metallurgical bonding layer. This leads to Cl⁻ ions easily penetrating along the ceramic / matrix interface in a corrosive environment, causing interfacial corrosion. Although CN110484786A discloses the preparation of core-shell structure particle-reinforced Al matrix composites using Ti powder and Al powder as raw materials, and CN110205536B discloses a titanium / titanium carbide core-shell structure reinforced aluminum matrix composite, the core-shell structures constructed by these technologies all use titanium or titanium compounds as the core reinforcing phase, which is fundamentally different from the core-shell structure of this application using ZrB2 as the core reinforcing phase in terms of material system and interface formation mechanism.

[0008] (4) External field-assisted dispersion technology has been applied in the ZrB2 / Al system, but it is mostly limited to improving the macroscopic dispersion uniformity and lacks precise control over the microstructure of the interface. Existing technologies have disclosed methods for preparing ZrB2 particles by using ultrasonic-electromagnetic coupling field-assisted dispersion. However, existing studies mainly focus on the effect of external field on improving the macroscopic dispersion uniformity of particles. There is no record in existing technologies on how to use the synergistic effect of external field and kinetic parameters such as reaction time and temperature field to precisely control the thickness of the nanoscale interface transition layer. More importantly, ultrasonic-electromagnetic coupling field treatment in existing studies is mainly for the purpose of assisting dispersion. There are no reports on combining it with ball milling pre-attachment technology to achieve precise control of the Al3Zr transition layer thickness by adjusting the amount of Zr source added and the melt contact time.

[0009] (5) There is still a lack of effective material solutions for improving the comprehensive performance of 2-series aluminum alloys under friction-corrosion coupled environments. In harsh service environments such as marine aircraft, load-bearing components need to withstand high-stress cyclic loads, high-speed impacts from high-concentration salt spray, and wide temperature fluctuations simultaneously, resulting in accelerated degradation of materials due to friction-corrosion synergy. Although existing technologies have reported the performance of ZrB2 particle-reinforced aluminum matrix composites under isolated salt spray environments or isolated friction conditions, research on the comprehensive performance under friction-corrosion coupled environments remains lacking.

[0010] Therefore, developing a composite material that can simultaneously improve the wear resistance and corrosion resistance of 2-series aluminum alloys, with strong interfacial bonding between the reinforcing phase and the matrix and uniform particle dispersion, and its preparation method, has significant engineering application value and broad market prospects. Summary of the Invention

[0011] The purpose of this invention is to overcome the above-mentioned defects in the prior art and provide a wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy, its preparation method and application.

[0012] Specifically, the present invention aims to solve the following technical problems: First, this invention addresses the problem that existing in-situ reaction methods generate ZrB2 and Al3Zr in an aluminum matrix with random distribution and lack of active control over the topological structure of the reinforcing phase space. In existing technologies, ZrB2 and Al3Zr are parallel reinforcing phases that are simultaneously and randomly generated in the aluminum melt. Al3Zr may nucleate independently or randomly attach to the surface of ZrB2 particles, failing to form a core-shell structure with ideal interfacial bonding strength. This invention utilizes ball milling pre-attachment of externally added nano-ZrB2 particles and nano-Zr powder, followed by a short-time confined reaction, to enable the directional in-situ growth of Al3Zr on the surface of nano-ZrB2 particles, constructing a ZrB2@Al3Zr core-shell structure and achieving active design of the topological morphology of the reinforcing phase space.

[0013] Secondly, this invention addresses the shortcomings of existing dual-scale particle reinforcement technologies in synergistically optimizing corrosion resistance and wear resistance. Current dual-scale reinforcement technologies primarily focus on improving mechanical properties (tensile strength, hardness), lacking systematic research on how the ratio of micron-sized to nano-sized ZrB2 particles simultaneously affects both corrosion resistance and wear resistance. This invention achieves a synergistic reinforcement effect of dual-scale particles in both corrosive and wear environments by optimizing the mass ratio of micron-sized to nano-sized ZrB2.

[0014] Third, this invention addresses the problem of insufficient interfacial bonding strength between the ceramic phase and the aluminum matrix when adding nano-ZrB2 particles. Existing methods for bonding the added ZrB2 particles to the aluminum matrix primarily rely on physical adsorption and mechanical intercalation, lacking a metallurgical bonding layer. This allows Cl⁻ ions to easily penetrate along the interface, initiating interfacial corrosion. This invention constructs an Al₃Zr transition layer on the surface of the nano-ZrB2 particles, coherently matched with the aluminum matrix, achieving a stepped lattice transition from the ceramic core to the metal matrix, significantly improving the interfacial bonding strength.

[0015] Fourth, this invention addresses the problem that existing external field-assisted dispersion technologies only focus on macroscopic particle uniformity and lack precise control over nanoscale interface structures. Current ultrasonic-electromagnetic coupling field treatments are mainly used to break up powder agglomeration and promote macroscopic particle dispersion in the melt, but research on how to control the thickness of the nanoscale interface transition layer using kinetic parameters is lacking. This invention precisely controls the thickness of the Al3Zr transition layer to 5–8 nm by controlling the amount of nano-Zr powder added and an extremely short melt contact time of 5–15 minutes, utilizing the melt diffusion kinetic confinement mechanism.

[0016] Fifth, it provides a wear-resistant and corrosion-resistant material solution for harsh service environments such as marine aircraft, capable of withstanding high-stress cyclic loads, high-speed impacts from high-concentration salt spray, and wide temperature fluctuations.

[0017] To solve the above-mentioned technical problems, the first aspect of the technical solution provided by the present invention is: A wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy, composed of the following components: a. The base material is a 2-series aluminum alloy; b. Micron-sized ZrB2 particles, with a particle size of 5–10 μm, accounting for 0.01%–0.2% of the mass percentage in the matrix aluminum alloy; c. Nano-sized ZrB2 particles, with a particle size of 30–100 nm, constitute 0.2%–1.0% of the mass percentage of the matrix aluminum alloy; Furthermore, the mass ratio of micron-sized ZrB2 particles to nano-sized ZrB2 particles is 1:3 to 1:6; The surface of the nano ZrB2 particles has an Al3Zr transition layer, which forms a coherent or semi-coherent matching interface with the 2-series aluminum alloy matrix. The thickness of the Al3Zr transition layer is 5-8 nm.

[0018] In the above technical solution, micron-sized ZrB2 particles bear the main load and resist abrasive wear in the matrix. Their large size enables them to withstand the main normal contact stress, effectively blocking the micro-cutting path of hard abrasives in the softer aluminum matrix and inhibiting the formation of ploughing grooves. Nano-sized ZrB2 particles, due to their high density, are widely dispersed within the grains and at grain boundaries, hindering dislocation slip and climb through the Orowan bypass mechanism, thus improving local micro-yield strength. The synergistic effect of the two-scale ZrB2 particles forms a multi-scale toughening structure that macroscopically resists ploughing and microscopically pinns to inhibit plastic deformation.

[0019] In a preferred embodiment, the mass percentage of the micron-sized ZrB2 particles is 0.08%–0.12%, the mass percentage of the nano-sized ZrB2 particles is 0.45%–0.55%, and the mass ratio of micron-sized ZrB2 particles to nano-sized ZrB2 particles is 1:4.5–1:5.5. Experiments show that this preferred ratio can achieve the best synergistic improvement in corrosion resistance and wear resistance in a 2-series aluminum alloy matrix.

[0020] In a preferred embodiment, the 2-series aluminum alloy comprises, by mass percentage: 4.0%–4.8% copper, 0.6%–0.8% magnesium, 0.8%–1.0% manganese, and 0.4%–0.5% silicon, with the balance being aluminum and unavoidable impurities. 2-series aluminum alloys within this composition range exhibit good interfacial compatibility with the ZrB2@Al3Zr core-shell structure, which is beneficial for the formation and stabilization of coherent / semi-coherent interfaces.

[0021] The second aspect of the technical solution provided by this invention is: The preparation method of the above-mentioned wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy includes the following steps: S1. Preparation of precursor composite powder: Weigh micron-sized ZrB2 powder with a particle size of 5-10 μm and nano-sized ZrB2 powder with a particle size of 30-100 nm, with a mass ratio of micron-sized ZrB2 powder to nano-sized ZrB2 powder of 1:3-1:6; Weigh nano-sized Zr powder with a particle size of 30-80 nm at a ratio of 0.5%-1.5% of the total mass of the nano-sized ZrB2 powder; Mix the above powder with Al powder at a mass ratio of 25-35:65-75 using high-energy ball milling to make the nano-sized Zr powder adhere to the surface of the nano-sized ZrB2 particles, and dry to obtain the precursor composite powder.

[0022] The key technology of this step lies in the fact that the nano-Zr powder and nano-ZrB2 particles are similar in size (30-100 nm vs. 30-80 nm). Through the mechanochemical action of high-energy ball milling, the nano-Zr powder can uniformly adhere to the surface of the nano-ZrB2 particles, forming a Zr@ZrB2 precursor structure. This allows the Zr source to be bound to the surface of the ZrB2 particles before the powder enters the aluminum melt, thus confining the Al3Zr generated in the subsequent melt reaction to the peripheral micro-regions of the ZrB2 particles. This achieves precise construction of the core-shell structure, unlike the uncontrollable distribution mode in existing technologies where ZrB2 and Al3Zr are randomly generated in the melt and Al3Zr can nucleate independently.

[0023] S2. Melt treatment: The 2-series aluminum alloy billet is heated to 740-780℃ to melt, and a degassing agent is added for degassing treatment. Then the aluminum alloy melt is cooled to 610-630℃.

[0024] S3. Interface reaction: The precursor composite powder obtained in step S1 is wrapped with two layers of aluminum foil and heated to 480-520℃ and held for 1-3 hours. It is then quickly pressed into the molten aluminum alloy obtained in step S2. While mechanically stirring at 1000-1200 rpm / min, an ultrasonic-electromagnetic coupling field is applied to control the contact time of the precursor composite powder in the molten aluminum alloy to be 5-15 minutes. By controlling the amount of nano Zr powder added and the contact time, an Al3Zr transition layer with a thickness of 5-8 nm is generated on the surface of the nano ZrB2 particles. Then, the temperature is raised to 720-740℃ and cast to obtain a billet.

[0025] The core technology of this step lies in controlling the thickness of the Al3Zr transition layer using a diffusion kinetic confinement mechanism. When nano-ZrB2 particles with attached nano-Zr powder enter the aluminum melt, Zr atoms react with Al atoms at the interface to generate Al3Zr. Studies have shown that the growth rate of Al3Zr in the Al-Zr system is proportional to the 1 / 3 power of time (see reference 1: Mingard K.P., Cantor B. Microstructural characterization of reactions in Al–Zr thinfilm couples. Journal of Materials Research, 1993, 8(2): 274-284). Therefore, by strictly controlling the melt contact time within an extremely short range of 5 to 15 minutes, the excessive growth of the Al3Zr layer can be suppressed, limiting its thickness to the range of 5 to 8 nm.

[0026] The ultrasonic-electromagnetic coupling field plays the following roles in this step: the microjets generated by ultrasonic cavitation can peel off the original oxide film and gas-encapsulated layer on the surface of nano-ZrB2 particles, exposing high-energy crystal planes, thereby reducing the activation energy of heterogeneous nucleation of Al3Zr on its surface; the Lorentz force of the electromagnetic field promotes macroscopic uniform dispersion of particles in the melt and prevents particle agglomeration. The parameters of the ultrasonic-electromagnetic coupling field treatment are: ultrasonic power of 800–1200 W, frequency of 20–25 kHz; pulsed magnetic field strength of 0.3–0.5 T, frequency of 5–10 Hz.

[0027] It is important to emphasize that the thickness of the Al3Zr transition layer is mainly controlled by diffusion kinetic parameters: reaction temperature, reaction time, and element concentration gradient, rather than directly by an external field. The function of the external field is to assist in dispersion and surface activation, creating favorable conditions for the interfacial reaction; the thickness control is achieved by the amount of nano-Zr powder added and the extremely short reaction contact time. The two work together to form a complete 5-8 nm thickness control technology scheme. Regarding the thickness control relationship between the growth of the interfacial transition layer and the reaction time, there have been many studies reported in this field. For example, in the study of Al / SiO2 layered nanosystems, the thickness of the interfacial diffusion barrier layer affects the self-heating rate of the aluminothermic reaction. The higher the initial temperature, the thinner the interfacial layer is formed, and the shorter the time required (see reference 2: "Molecular dynamics simulation of the aluminothermic reaction of Al / SiO2 layered structure nanothermostat", Acta Physica Sinica, 2014, 63(8): 086401). In Al-Ni reaction multilayer films, the interfacial reaction is also controlled by diffusion kinetics. The above studies support the diffusion kinetic confinement logic from short reaction time to thin interfacial layer from both experimental and theoretical perspectives.

[0028] S4. Hot deformation and heat treatment: The billet is homogenized at 460-480℃ for 10-12 hours, and then hot-rolled at 430-450℃ with a total deformation of 70%-85%; after hot rolling, solution aging treatment is performed at 500-510℃ for 2-2.5 hours and at 160-170℃ for 11-13 hours.

[0029] The third aspect of the technical solution provided by this invention is: Application of the aforementioned wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloys in load-bearing components of marine aircraft subjected to the following coupled working conditions: Cyclic alternating contact stress not less than 100 MPa; High-speed impact salt spray environment with chloride ion concentration not less than 30 g / L, and impact linear velocity of salt spray relative to component surface not less than 10 m / s; The temperature fluctuation range is -20℃ to +80℃; Furthermore, the high-speed impact of the salt spray and the cyclic contact stress generate a synergistic effect of friction and corrosion that accelerates degradation.

[0030] In a preferred embodiment, the load-bearing components of the marine aircraft are selected from at least one of landing gear components, wing connectors, fuselage frame connectors, engine mounts, and flap rails.

[0031] Compared with the prior art, the present invention achieves the following beneficial technical effects: This invention achieves, for the first time, the directional construction of a ZrB2@Al3Zr core-shell structure in ZrB2-reinforced 2-series aluminum alloys, differing from the random melt generation mode of existing technologies. Existing technologies disclose the addition of Zr and B elements to aluminum melt to generate nano-ZrB2 ceramic reinforcements through in-situ reactions, simultaneously producing an Al3Zr phase. However, in this approach, ZrB2 and Al3Zr are generated simultaneously and randomly within the melt; Al3Zr may nucleate independently or randomly attach to the surface of ZrB2 particles, lacking active control over the spatial arrangement of the reinforcing phases. This invention, for the first time, employs a high-energy ball milling technique to attach nano-Zr powder to the surface of nano-ZrB2 particles and a short-time confined reaction, ensuring that Zr atoms and Al atoms react only in micro-regions on the ZrB2 particle surface. The generated Al3Zr is confined to the periphery of the ZrB2 particles, forming a coating layer, thus preventing independent nucleation of Al3Zr within the melt. This pre-attachment and confined reaction technique achieves precise construction of the core-shell structure.

[0032] This invention achieves nanoscale precise control of the AlZr transition layer thickness through a diffusion kinetic confinement mechanism. While existing research has revealed the growth kinetics of Al3Zr (growth rate ∝ t^(1 / 3)), it has not been applied to the thickness control of the transition layer at the composite material interface. This invention, for the first time, uses the reaction contact time as an active design variable. By strictly controlling the melt contact time within the range of 5–15 minutes, and utilizing the slow increase in the Al3Zr growth rate over time, the transition layer thickness is limited to 5–8 nm, avoiding the drawbacks of excessive Al3Zr growth leading to the destruction of interfacial coherence and the formation of brittle phases. This technical concept is pioneering in the field of ZrB2-reinforced aluminum matrix composites.

[0033] This invention reveals a nonlinear correlation between a specific ratio of dual-scale ZrB2 particles and their wear and corrosion resistance, constituting a selective invention with "unexpected technical effects." While existing technologies disclose a wide range of mixing ratios of micron-sized and nano-sized ZrB2 powders from 1:1 to 1:5, they have not systematically studied the impact of each specific ratio within this range on corrosion and wear resistance. This application, through experiments, found that when the mass ratio of micron-sized to nano-sized ZrB2 particles is controlled within 1:4.5 to 1:5.5, particularly at 0.1% micron and 0.5% nano-sized particles, the self-corrosion current density and volumetric wear rate of the material exhibit a significant and precipitous decrease, showing a clear preferred range. When the mass ratio deviates from this range to 1:3 or 1:6, the performance deteriorates significantly.

[0034] This invention provides an Al3Zr transition layer that forms a coherent / semi-coherent matched interface with the Al matrix, significantly improving interfacial bonding strength and suppressing interfacial corrosion and brittle phase formation. The low lattice mismatch (approximately 2.7%) between Al3Zr and the Al matrix allows for the formation of a coherent or semi-coherent matched interface within the aluminum matrix. By confining Al3Zr to the surface of nano-ZrB2 particles, this coherent interface is used to optimize the interfacial state of the ZrB2-reinforced phase. The presence of the Al3Zr transition layer not only suppresses the risk of direct reaction between ZrB2 and the Al matrix during high-temperature processing, potentially forming brittle phases, but also serves as a heterogeneous nucleation core, further refining the grain size. In corrosive environments, the dense Al3Zr transition layer effectively blocks the penetration of Cl⁻ ions along the ZrB2 / Al interface, significantly improving the material's corrosion resistance.

[0035] This invention utilizes the synergistic combination of ultrasonic-electromagnetic coupling field treatment and diffusion kinetics confinement mechanism to form a complete integrated technical solution for assisted dispersion, interface activation, and thickness control, which differs from the single-function positioning of existing external field-assisted dispersion technologies. In existing technologies, ultrasonic-electromagnetic coupling fields are mainly used to break powder agglomeration and promote uniform dispersion of particles in the melt. This invention is the first to synergize ultrasonic-electromagnetic coupling field with diffusion kinetics confinement mechanism. Ultrasonic cavitation is responsible for stripping the oxide film on the particle surface, exposing high-energy crystal planes, and reducing the activation energy of Al3Zr heteronucleation; the electromagnetic field is responsible for promoting macroscopic uniform dispersion of particles; and thickness control is achieved by the amount of nano-Zr powder added and the extremely short reaction contact time. The three work together to form a complete technical solution for controlling the thickness of the 5-8nm transition layer, effectively solving the technical problem of the difficulty in accurately controlling the nanoscale interface structure with an external field.

[0036] This invention provides a solution for the application of materials in friction-corrosion coupled environments, a topic not addressed in existing technologies. Existing technologies primarily focus on the preparation methods and conventional mechanical properties of dual-scale ZrB2 particle-reinforced aluminum matrix composites, neglecting the application of such materials in load-bearing components of marine aircraft and other applications subjected to high stress, high-concentration salt spray impacts at high speeds, and wide temperature fluctuations in friction-corrosion coupled environments. This invention is the first to propose applying a specific ratio of dual-scale ZrB2 particle-reinforced 2-series aluminum alloys to these extreme coupled conditions, and provides the key performance indicators that the material should meet under these conditions, constituting a creative application invention. Attached Figure Description

[0037] Figure 1 These are dry sliding friction and wear surface morphology images of ZrB2 particle-reinforced 2-series aluminum alloys with different sizes and ratios. (a) Comparative Example 1: pure matrix; (b) Comparative Example 2: 50 nm, 0.1%; (c) Comparative Example 4: 50 nm, 1%; (d) Comparative Example 6: 10 μm, 0.5%; (e) Comparative Example 7: dual-scale 1:1; (f) Optimal dual-scale 1:5 of Example 1; (g) Comparative Example: 350 nm, 0.5%; (h) Comparative Example 5: 10 μm, 0.1%.

[0038] Figure 2 These are Nyquist impedance diagrams of the comparative and example samples in 3.5% NaCl solution.

[0039] Figure 3 These are surface morphology images of the matrix alloy and some comparative and example samples after electrochemical etching in 3.5% NaCl solution. Among them: (a) pure matrix of Comparative Example 1; (b) 0.5% of Comparative Example 3 at a single scale of 50 nm; (c) 0.1% of Comparative Example 5 at a single scale of 10 μm; (d) 1:1 of Comparative Example 7 at a non-preferred dual scale. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. However, the scope of protection of this invention is not limited to the following embodiments, and all equivalent modifications or substitutions made based on the technical solutions of this invention fall within the scope of protection of this invention.

[0041] The measured composition of the 2-series aluminum alloy matrix used in all embodiments and comparative examples of this invention, by mass percentage, is as follows: copper 4.173%, magnesium 0.640%, manganese 0.941%, silicon 0.489%, iron 0.015%, titanium 0.013%, with the balance being aluminum and unavoidable impurities.

[0042] Example 1: The preferred embodiment of the present invention, with a dual-scale micro / nano ratio of 1:5, corresponding to a total content of 0.6%. This embodiment prepares a wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy, and the specific steps are as follows: S1. Preparation of core-shell precursor composite powder: 10g of micron-sized ZrB2 powder with a particle size of 10μm and 50g of nano-sized ZrB2 powder with a particle size of 50nm were weighed, with a micron to nano mass ratio of 1:5. 0.5g of nano-sized Zr powder with a particle size of 50nm was weighed as 1.0% of the total mass of the nano-ZrB2 powder. The above powders were mixed with Al powder at a mass ratio of 30:70 using high-energy ball milling (ball-to-powder ratio 8:1), at a speed of 200rpm / min, for 24h. Scanning electron microscopy (SEM) and EDS surface scanning revealed that under this mechanochemical action, the highly active nano-Zr powder was densely and uniformly pre-attached to the surface of the nano-ZrB2 particles through a cold welding effect, forming a Zr@ZrB2 precursor. No independent free Zr powder agglomerates were observed. The precursor was dried and stored for later use.

[0043] S2. Melt treatment: The rough 2-series aluminum alloy billet is placed in an electric resistance furnace and heated to 760℃~780℃ to melt. A dried impurity remover is added for degassing and refining. After standing, the aluminum alloy melt is then cooled to 620℃.

[0044] S3. Kinetic Confined Reaction: Weigh an appropriate amount of the precursor composite powder obtained in step S1, ensuring the total ZrB2 particle content in the composite material accounts for 0.6% of the matrix mass. Wrap it in two layers of aluminum foil and heat to 500℃ for two hours. Then, remove it and quickly press it below the surface of the molten aluminum alloy. While mechanically stirring at 1100 rpm / min, apply an ultrasonic-electromagnetic coupling field treatment: ultrasonic power 1000W, frequency 20kHz; pulsed magnetic field strength 0.4T, frequency 8Hz. Strictly control the contact reaction time of the precursor powder in the melt to 10 minutes. Utilizing this extremely short diffusion kinetic confined mechanism, the pre-attached Zr atoms undergo a micro-region in-situ reaction with Al in the melt. Subsequently, heat to 730℃ and pour into a preheated mold at 250℃ to form the final product.

[0045] S4. Hot deformation and heat treatment: The billet is homogenized at 480℃ for 12 hours; hot rolling deformation is carried out at 440℃ with a deformation amount of 80%; then solution treatment is carried out at 500℃ for 2 hours, followed by room temperature water quenching and aging treatment at 160℃ for 12 hours.

[0046] Microstructural characterization and high-resolution transmission electron microscopy (HRTEM) observations revealed that the material prepared using the above process successfully formed a highly uniform Al3Zr shell of approximately 6 nm thickness around the nano-ZrB2 particles, creating a perfect ZrB2@Al3Zr core-shell structure. This Al3Zr shell exhibits excellent semi-coherent matching with the α-Al matrix, and the interface is clean and free of micropores.

[0047] To verify the control effect of the contact reaction time on the core-shell thickness in step S3, the influence of the kinetic confinement time on the transition layer thickness was verified. Based on Example 1, only the melt contact reaction time in step S3 was changed: In the comparison verification group 1, after 3 minutes of reaction, the Al3Zr transition layer was less than 2nm thick, the coating was incomplete, and it could not effectively resist Cl⁻ erosion.

[0048] In the comparison and verification group 2, after 30 minutes of reaction, Zr atoms diffused excessively into the melt, and the Al3Zr layer grew excessively to 18~25nm. Not only was the interfacial coherence severely disrupted, but some coarse and brittle Al3Zr phases also detached into the matrix, resulting in a sharp decrease in the toughness of the material.

[0049] The above results confirm that controlling the confinement reaction time to 5-15 minutes is the only necessary condition for obtaining an ideal core-shell thickness of 5-8 nm.

[0050] To verify the unexpected technical effect of the dual-scale ratio of 1:3 to 1:6, especially the preferred range of 1:4.5 to 1:5.5, the following examples and comparative examples were prepared. The preparation process was the same as in Example 1, only the additive ratio was changed: Comparative Example 1: Pure 2-series matrix alloy, without added reinforcing particles.

[0051] Comparative Example 2: Single scale, with 50nm ZrB2 added, content 0.1%.

[0052] Comparative Example 3: Single scale, with 50nm ZrB2 added, content 0.5%.

[0053] Comparative Example 4: Single scale, with 50nm ZrB2 added, content 1.0%.

[0054] Comparative Example 5: Single scale, with 10 μm ZrB2 added, content 0.1%.

[0055] Comparative Example 6: Single scale, with 10 μm ZrB2 added, content 0.5%.

[0056] Comparative Example 7: Dual-scale non-preferred, with a micrometer to nanometer ratio of 1:1, i.e., 0.1% micrometer and 0.1% nanometer.

[0057] Comparative Example 8: Dual-scale non-preferred, with a micrometer to nanometer ratio of 1:3, i.e., 0.1% micrometer and 0.3% nanometer.

[0058] Comparative Example 9: Dual-scale deviation range, micrometer to nanometer ratio 1:6, i.e. 0.1% for micrometers and 0.6% for nanometers.

[0059] Example 2: The present invention preferably has dual-scale lower limits, with a ratio of 1:4.5, that is, 0.1% for micrometers and 0.45% for nanometers.

[0060] Example 3: The present invention preferably has a dual-scale upper limit, with a ratio of 1:5.5, that is, 0.1% micrometer + 0.55% nanometer.

[0061] Performance test results and chart analysis: Electrochemical corrosion test (3.5% NaCl solution) and room temperature dry sliding friction and wear test were performed on all the above samples. The core test data are detailed in Table 1.

[0062] Table 1. Effect of ZrB2 particles of different sizes and ratios on the comprehensive properties of the matrix alloy The mechanism analysis is as follows, with reference to the attached figures: (1) Wear mechanism analysis: such as Figure 1 As shown, pure matrix Figure 1 Example a exhibits typical severe furrowing and adhesive wear morphology, with the highest wear rate; while the preferred embodiment of the present invention, 1... Figure 1The friction surface of f is extremely smooth, with only minor scratches. This is because when the dual-scale ratio is within the optimal range of 1:4.5 to 1:5.5, the micron-sized particles form a macroscopic load-bearing skeleton to resist mechanical ploughing, while the nanoparticles with the Al3Zr core-shell structure strongly pinnate the dislocation network at the microscopic level, effectively suppressing the plastic flow of the matrix. The two produce a nonlinear synergistic anti-wear effect. When the ratio deviates from this range, such as the 1:1 ratio in Comparative Example 7, Figure 1 e. The collaborative bearing mechanism cannot be fully utilized, and deeper furrows reappear on the surface.

[0063] Corrosion mechanism analysis: such as Figure 2 As shown in the Nyquist impedance spectrum, the core embodiment 1 of this invention is... Figure 2 The charge transfer resistance of the curve with the largest capacitive arc radius reached the highest level, and the self-corrosion current density decreased by a full order of magnitude, reaching 10⁻⁻⁴, compared to the single-scale curve. 7 The A / cm² level demonstrates its superior corrosion resistance. Combined with... Figure 3 Further verification using corrosion surface morphology images shows that the pure substrate... Figure 3 a. Single-scale comparative example 3 Figure 3 b and Comparative Example 5 Figure 3 c, and Comparative Example 7 with non-optimal proportions. Figure 3 The surface exhibits pitting, corrosion products, and corrosion cracks to varying degrees; this clearly demonstrates that single-scale particles or improperly proportioned dual-scale particles easily induce galvanic corrosion at the micro-interface, failing to effectively block Cl⁻ penetration. Furthermore, combined with... Figure 2 Impedance spectroscopy reveals that the material prepared using the preferred process of this invention exhibits a significant improvement in corrosion resistance due to the dense and stable ZrB2@Al3Zr coherent core-shell structure on its surface, which completely blocks the penetration channels of Cl⁻ ions along the ceramic / metal interface.

[0064] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention described herein.

Claims

1. A wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy, characterized in that, It consists of the following components: (a) The matrix is ​​a 2-series aluminum alloy; (b) Micron-sized ZrB2 particles with a diameter of 5–10 μm, comprising 0.01%–0.2% of the mass of the matrix aluminum alloy; (c) Nano ZrB2 particles with a particle size of 30–100 nm, comprising 0.2%–1.0% by mass in the matrix aluminum alloy; Furthermore, the mass ratio of micron-sized ZrB2 particles to nano-sized ZrB2 particles is 1:3 to 1:6; The surface of the nano ZrB2 particles has an Al3Zr transition layer, which forms a coherent or semi-coherent matching interface with the 2-series aluminum alloy matrix. The thickness of the Al3Zr transition layer is 5-8 nm.

2. The wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy according to claim 1, characterized in that, The mass percentage of the micron-sized ZrB2 particles is 0.08% to 0.12%, the mass percentage of the nano-sized ZrB2 particles is 0.45% to 0.55%, and the mass ratio of the micron-sized ZrB2 particles to the nano-sized ZrB2 particles is 1:4.5 to 1:5.

5.

3. The wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy according to claim 1, characterized in that, The 2-series aluminum alloy contains, by mass percentage: 4.0%–4.8% copper, 0.6%–0.8% magnesium, 0.8%–1.0% manganese, 0.4%–0.5% silicon, with the balance being aluminum and unavoidable impurities.

4. A method for preparing a wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy as described in any one of claims 1 to 3, characterized in that, Includes the following steps: S1. Preparation of precursor composite powder: Weigh micron-sized ZrB2 powder with a particle size of 5-10 μm and nano-sized ZrB2 powder with a particle size of 30-100 nm, with a mass ratio of micron-sized ZrB2 powder to nano-sized ZrB2 powder of 1:3-1:6; Weigh nano-sized Zr powder with a particle size of 30-80 nm at a ratio of 0.5%-1.5% of the total mass of the nano-sized ZrB2 powder; Mix the above powder with Al powder at a mass ratio of 25-35:65-75 using high-energy ball milling to make the nano-sized Zr powder adhere to the surface of the nano-sized ZrB2 particles, and dry to obtain the precursor composite powder; S2. Melt treatment: The 2 series aluminum alloy billet is heated to 740-780℃ to melt, and a degassing agent is added for degassing treatment. Then the aluminum alloy melt is cooled to 610-630℃. S3. Interface reaction: The precursor composite powder obtained in step S1 is wrapped with two layers of aluminum foil and heated to 480-520℃ and held for 1-3 hours. It is then quickly pressed into the molten aluminum alloy obtained in step S2. While mechanically stirring at 1000-1200 rpm / min, an ultrasonic-electromagnetic coupling field is applied to control the contact time of the precursor composite powder in the molten aluminum alloy to be 5-15 minutes. By controlling the amount of nano Zr powder added and the contact time, an Al3Zr transition layer with a thickness of 5-8 nm is generated on the surface of the nano ZrB2 particles. Then, the temperature is raised to 720-740℃ and cast to obtain a billet. S4. Hot deformation and heat treatment: The billet is homogenized at 460-480℃ for 10-12 hours, and then hot-rolled at 430-450℃ with a total deformation of 70%-85%; after hot rolling, solution aging treatment is performed at 500-510℃ for 2-2.5 hours and at 160-170℃ for 11-13 hours.

5. The method for preparing wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy according to claim 4, characterized in that: In step S3, the parameters for the ultrasonic-electromagnetic coupling field processing are: ultrasonic power of 800-1200W and frequency of 20-25kHz; pulse magnetic field strength of 0.3-0.5T and frequency of 5-10Hz.

6. The application of the wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy according to any one of claims 1 to 3 in load-bearing components of marine aircraft subjected to the following coupled working conditions: Cyclic alternating contact stress not less than 100 MPa; High-speed impact salt spray environment with chloride ion concentration not less than 30 g / L, and impact linear velocity of salt spray relative to component surface not less than 10 m / s; The temperature fluctuation range is -20℃ to +80℃; Furthermore, the high-speed impact of the salt spray and the cyclic contact stress generate a synergistic effect of friction and corrosion that accelerates degradation.

7. The application of the wear-resistant and corrosion-resistant ZrB2 particle-reinforced 2-series aluminum alloy according to claim 6 in load-bearing components of marine aircraft subjected to the following coupled working conditions, characterized in that, The load-bearing components of the marine aircraft are selected from at least one of the following: landing gear components, wing connectors, fuselage frame connectors, engine mounts, and flap rails.

Images