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CN-122008635-A - High-strength and high-toughness corrosion-resistant cross aluminum alloy-based high-performance magnesium aluminum composite board and preparation method thereof

CN122008635ACN 122008635 ACN122008635 ACN 122008635ACN-122008635-A

Abstract

The invention belongs to the technical field of metal layered composite materials, and particularly relates to a magnesium-aluminum composite board based on high-strength-toughness corrosion-resistant cross aluminum alloy and a preparation method thereof. The composite board takes aluminum cross alloy as a multi-layer material, the aluminum cross alloy is Al-Mg-Zn- (Cu) series or Al-Mg-Cu series alloy, the magnesium content is 3.0-8.6wt%, and Zn/Mg is <1 or Cu/Mg is <1. The preparation method comprises the steps of carrying out heat treatment on a magnesium alloy plate, carrying out 45-degree cross polishing and cleaning on a composite interface, carrying out asynchronous rolling with small rolling reduction rate (25% -40%) to realize primary composite and interface structure control after assembling, carrying out intermediate heat treatment to optimize interface combination, and carrying out synchronous rolling with large rolling reduction rate (60% -80%) to strengthen combination and optimize plate shape. The invention utilizes the unique property of the aluminum cross alloy, and the prepared composite board has the advantages of high interface bonding strength, good overall toughness, flat board shape, good corrosion resistance and the like, and is particularly suitable for traffic equipment structural members with severe requirements on light weight, safety and formability.

Inventors

  • WU ZHENYU
  • WANG XIANGJIE
  • Gou Lumin
  • CUI JIANZHONG

Assignees

  • 东北大学

Dates

Publication Date
20260512
Application Date
20260212

Claims (10)

  1. 1. The high-performance magnesium-aluminum composite board based on the high-strength and high-toughness corrosion-resistant cross aluminum alloy is characterized by comprising a cross aluminum alloy layer and a magnesium alloy layer, wherein the cross aluminum alloy layer and the magnesium alloy layer form a metallurgical bonding interface through rolling and compounding, and the thickness ratio of the cross aluminum alloy layer to the magnesium alloy layer is 1:2.8-1:3.8.
  2. 2. The high performance magnesium aluminum composite panel according to claim 1, wherein said interdigitated aluminum alloy layer is an age-hardenable Al-Mg-Zn- (Cu) based alloy or an Al-Mg-Cu based alloy.
  3. 3. The high-performance magnesium aluminum composite board according to claim 2, wherein the Al-Mg-Zn- (Cu) alloy consists of, in mass percent, 3.0-8.6 wt% of Mg, 2.0-2.9 wt% of Zn, 0-1.0 wt% of Cu, 0.12-0.27 wt% of Sc, 0.12-0.36 wt% of Zr, the balance being Al and the Zn/Mg weight ratio being less than 1, and the Al-Mg-Cu alloy consists of, in mass percent, 3.0-8.6 wt% of Mg, 0.2-1.0 wt% of Cu, 0.12-0.27 wt% of Sc, 0.12-0.36 wt% of Zr, the balance being Al and the Cu/Mg weight ratio being less than 1.
  4. 4. The high-performance magnesium aluminum composite panel according to claim 3, wherein the Al-Mg-Zn- (Cu) alloy layer contains a main strengthening phase T-Mg32 (Al, zn, cu) 49 phase and a dispersed Al3 (Sc, zr) phase.
  5. 5. The high performance magnesium aluminum composite panel according to claim 1, wherein the metallurgical bonding interface between the interdigitated aluminum alloy layers and the magnesium alloy layers is a discontinuous, stepwise distributed intermetallic layer having a thickness of 0.5-5.0 microns.
  6. 6. A method for preparing the high-performance magnesium-aluminum composite board according to any one of claims 1 to 5, comprising the following steps: s1, preparing raw materials, namely preparing a crossed aluminum alloy plate and a magnesium alloy plate with equal length and width, wherein the thickness ratio of the crossed aluminum alloy plate to the magnesium alloy plate is 1:2.8-1:3.8; S2, pretreating the magnesium alloy plate, namely performing heat treatment on the magnesium alloy plate at the temperature of 300-450 ℃ for 120-360 minutes, and then performing air cooling to room temperature; s3, surface treatment and assembly, namely polishing and cleaning the surfaces to be compounded of the crossed aluminum alloy plates and the magnesium alloy plates to remove an oxide layer and oil stains, and then fixing the cleaned surfaces to be compounded in a riveting and binding mode to obtain a composite plate blank; S4, preheating the composite slab, namely heating the composite slab at 300-450 ℃ for 20-50 minutes; S5, asynchronous rolling, namely asynchronous rolling the preheated composite slab, wherein the rolling speed ratio of the magnesium side to the aluminum side is 1.15-1.35, the rolling reduction is 25-40%, and the rolling speed is 0.5-1.5 m/S; s6, intermediate heat treatment, namely performing heat treatment on the asynchronously rolled composite plate, controlling interface performance, wherein the heat treatment temperature is 300-450 ℃, and the heat preservation time is 10-30 minutes; And S7, synchronously rolling the heat-treated composite board, wherein the synchronous rolling reduction is 60-80%, and the final magnesium-aluminum composite board is obtained.
  7. 7. The method according to claim 6, wherein the heat treatment process in the step S2 is carried out at a heat treatment temperature of 350-400 ℃ for 150-180 minutes, and the intermediate heat treatment process in the step S6 is carried out at a heat treatment temperature of 300-450 ℃ for 15-25 minutes.
  8. 8. The method according to claim 6, wherein the polishing and cleaning in the step S3 is performed by using an angle grinder for cross polishing at 30-60 degrees, then using acetone and absolute ethyl alcohol for cleaning and air drying, and the assembly is formed by drilling holes in the head part of a plate blank and riveting the plate blank by using cross aluminum alloy rivets, and drilling holes in the tail part and binding the plate blank by using metal wires with the diameter of 1.5-3 mm.
  9. 9. The method according to claim 6, wherein the asynchronous rolling in step S5 is performed by same-diameter different-speed rolling or same-speed different-diameter rolling.
  10. 10. The method according to claim 6, further comprising a step of pre-aging the obtained magnesium aluminum composite panel after the synchronous rolling in step S7, wherein the pre-aging is performed for 3 to 12 hours at 80 to 120 ℃.

Description

High-strength and high-toughness corrosion-resistant cross aluminum alloy-based high-performance magnesium aluminum composite board and preparation method thereof Technical Field The invention belongs to the technical field of metal layered composite materials, and particularly relates to a magnesium-aluminum composite board based on high-strength-toughness corrosion-resistant cross aluminum alloy and a preparation method thereof. The invention adopts a novel cross aluminum alloy as a multi-layer material, and realizes the cooperative promotion of interface bonding strength, integral mechanical property and plate shape quality through an optimized asynchronous-synchronous composite rolling process. Background Light weight is one of the core trends of the high-end equipment manufacturing industry of aerospace, new energy automobiles and the like. Magnesium alloy has extremely high specific strength and specific rigidity as the lightest metal structural material, but has the defects of low absolute strength, poor corrosion resistance and poor room temperature formability, which limits the wide application. Aluminum alloys, particularly 5xxx series (Al-Mg), have good formability and corrosion resistance but limited strength and cannot be strengthened by heat treatment, whereas 2xxx (Al-Cu-Mg) and 7xxx (Al-Zn-Mg-Cu) series aluminum alloys have very high strength but poor formability. The performance of traditional single materials is difficult to meet the integration requirement of modern structural parts on high formability and high strength. In order to achieve both the light weight advantage of magnesium and the surface property of aluminum, magnesium-aluminum composite panels have been developed. Rolling compounding is the predominant process for preparing such layered composites. However, the traditional rolling compounding method for preparing the magnesium-aluminum composite plate has two major core challenges, namely firstly, remarkable difference of physical and mechanical properties of magnesium and aluminum, difficulty in coordination in the deformation process, easiness in forming continuous and brittle intermetallic compounds (such as Al3Mg2 and Mg17Al 12) at the interface, serious deterioration of mechanical properties and subsequent processing capacity of the composite plate, and secondly, asynchronous rolling can reduce rolling force and promote interface compounding, and multi-pass rolling can easily cause serious plate-shaped warping and aggravate growth of the interface compounds, and negative influence is generated on the bonding strength. The recently proposed design concept of 'cross alloy' (such as Al-Mg-Zn- (Cu)) enables the alloy to have excellent formability of a 5xxx system and high strength of a 7xxx system through component optimization, and provides a new idea for developing a high-performance layered composite material. However, no research is currently done on compounding such leading-edge cross aluminum alloys with magnesium alloys, and there is no compounding preparation process matching with the same. Therefore, the high-performance magnesium-aluminum composite board based on the crossed aluminum alloy and matched with the precise interface and plate shape control technology and the preparation method thereof are developed, and the high-performance magnesium-aluminum composite board has important theoretical value and wide application prospect. Disclosure of Invention The invention mainly aims to overcome the defects of low interfacial bonding strength, poor plate shape quality and difficult compatibility of the strength and formability of a composite material of the existing magnesium-aluminum composite plate, and provides a high-performance magnesium-aluminum composite plate based on high-strength high-toughness corrosion-resistant cross aluminum alloy and a preparation method thereof. According to the invention, through combination of innovative material design and preparation process, the synergistic improvement of the interface bonding strength, the overall mechanical property and the plate shape quality of the composite plate is realized. In order to achieve the purpose, the invention adopts the following technical scheme: On one hand, the invention provides a high-performance magnesium-aluminum composite board based on high-strength and high-toughness corrosion-resistant cross aluminum alloy. The composite board comprises an intersecting aluminum alloy layer and a magnesium alloy layer, and the intersecting aluminum alloy layer and the magnesium alloy layer are rolled and compounded to form a metallurgical bonding interface. The crossed aluminum alloy is an age-hardenable Al-Mg-based alloy, which is selected from one or a combination of two systems, namely an Al-Mg-Zn- (Cu) alloy, and consists of, in mass percent, 3.0-8.6 wt% of Mg, 2.0-2.9 wt% of Zn, 0-1.0 wt% of Cu, 0.12-0.27 wt% of Sc, 0.12-0.36 wt% of Zr, the balance of Al, and the weight ratio of Zn/Mg is less than