Preparation method of particle-reinforced magnesium-lithium-aluminum-calcium-silicon alloy plate

Abstract

The invention relates to a preparation method of a particle-reinforced magnesium-lithium-aluminum-calcium-silicon alloy plate, and the preparation method is designed for aiming at a situation that a magnesium-lithium alloy is low in strength, poor in heat resistance and unstable in mechanical properties. The method comprises the following steps: preparing an aluminum-silicon eutectic alloy and a magnesium-aluminum-calcium eutectic alloy firstly; carrying out high-frequency induced heating and melting as well as suction casting on the alloys so as to obtain a magnesium-lithium-aluminum-calcium-silicon alloy ingot; and rolling the alloy ingot by using a roller mill, so that the magnesium-lithium-aluminum-calcium-silicon alloy plate is prepared. The preparation method is advanced in process and detailed and accurate in data, the size of reinforced particles is less than and equal to 200 nm, the reinforced particles are uniformly distributed in an alloy beta-Li matrix, alpha-Mg crystal particles are refined until the granularity of 10 mu m, the yield strength of alloys is 298 Mpa, the tensile strength is 320 Mpa, the elongation reaches 7%, and the mechanical properties of the magnesium-lithium-aluminum-calcium-silicon alloy plate are improved, and the application range of the magnesium-lithium-aluminum-calcium-silicon alloy plate is enlarged, so that the method disclosed by the invention is an extremely ideal reinforced preparation method of a magnesium-lithium-aluminum-calcium-silicon alloy plate.

Description

technical field [0001] The invention relates to a method for preparing a particle-reinforced magnesium-lithium-aluminum-calcium-silicon alloy plate, which belongs to the technical field of nonferrous metal reinforcement preparation and application. Background technique [0002] Magnesium-lithium alloy is a non-ferrous light metal structural material, which has the characteristics of light weight, high specific strength and high toughness, and has broad application prospects in aviation, aerospace, and electronics industries; however, magnesium-lithium alloys have low strength, unstable mechanical properties, The heat resistance is poor, and it is difficult to meet the mechanical performance requirements of bearing parts, which limits its application range as a structural material; at present, the strengthening methods of magnesium-lithium alloys include: alloying method, Al, Zn, Ag, Cu, Sc, Y and Rare earth elements can effectively refine the grains, and enhance the strength...

AI Technical Summary

Problems solved by technology

[0002] Magnesium-lithium alloy is a non-ferrous light metal structural material, which has the characteristics of light weight, high specific strength and high toughness, and has broad application prospects in aviation, aerospace, and electronics industries; however, magnesium-lithium alloys have low strength, unstable mechanical properties, The heat resistance is poor, and it is difficult to meet the mechanical performance requirements of bearing parts, which limits its application range as a structural material; at present, the strengthening methods of magnesium-lithium alloys include: alloying method, Al, Zn, Ag, Cu, Sc, Y and Rare earth elements can effectively refine the grains, and enhance the strength of magnesium-lithium alloys through solid solution strengthening and precipitation strengthening; fine-grain strengthening method, control the cooling rate, add RE, Ca, Zr, Mn grain refiners, and perform equal channel rotation Extrusion refinement can achieve fine-grain strengthening effect; however, due to the lack of effective strengthening phase, it is difficult to make the strength of magnesium-lithium alloy reach 200MPa by alloying method and fine-grain strengthening method

[0003] Calcium can form a Laves phase similar to rare earths with magnesium and aluminum elements: Mg 2 Ca, Al 2 Ca, (Mg, Al) 2 Ca, with low cost and low density, is a potential strengthening phase in magnesium alloys. However, since calcium compounds mainly exist in the grain boundary or phase boundary in the form of eutectic skeleton, it is easy to deteriorate the mechanical properties of the alloy. Therefore, the calcium in magnesium-lithium alloys The amount of addition is greatly limited, and the strengthening effect is not obvious; while the magnesium-silicon phase can significantly improve the high-temperature strength and creep resistance of magnesium alloys, but its coarse structure splits the matrix, which is detrimental to the mechanical properties. It will cause great harm to the corrosion resistance of the alloy; therefore, to achieve effective strengthening of magnesium-lithium alloys, the strengthening phase particles should be ≤ 1 μm, and at the same time control the distribution to avoid the existence of coarse strengthening phases at the interface

Images