Preparation method for magnesium alloy with high strength and large plasticity

Abstract

The invention relates to a preparation method for magnesium alloy with high strength and large plasticity. The magnesium alloy comprises the following components (weight percentage): 3-6% of aluminum (Al), 1-3% of zinc (Zn), 1.0-2.0% of titanium (Ti), 0.35-0.8% of rhenium (RE) neodymium, yttrium, cerium and gadolinium (Nd, Y, Ce and Gd). The total amount of impurity elements including silicon, ferrum, copper and nickel (Si, Fe, Cu and Ni) is smaller than 0.02%, and the remain is magnesium (Mg). During smelting, pure magnesium, aluminum ingot and zinc ingot are melted in a smelting furnace, and the magnesium alloy is obtained by adding middle alloy in the smelting furnace, and solid solution strengthening treatment and aging treatment are performed on the magnesium alloy. The obtained magnesium alloy is characterized in that compared with AZ, ZK series magnesium alloy for commercial use, the magnesium alloy has the comprehensive performance of integrating high strength (>350MPa), high toughness (extension rate>20%), low density, good anti-flaming performance and the like.

Description

technical field [0001] The invention relates to a magnesium alloy and a preparation method thereof, in particular to a magnesium alloy with high strength and large plasticity prepared by microalloying and a preparation method thereof. It belongs to the field of metal materials and metallurgy. Background technique [0002] Magnesium alloys have broad application prospects in aerospace, military, electronics, machinery, automobiles and other industries, mainly due to their low density, impact resistance, excellent electromagnetic shielding performance, high specific strength and rigidity, and good machinability Features. Our country vigorously develops the magnesium alloy industry, not only has a strong resource advantage, but also has a huge market demand. [0003] However, in recent years, magnesium alloys have replaced aluminum alloys and other materials, and the application development in various industries has been relatively slow. The main reason is that magnesium allo...

AI Technical Summary

Problems solved by technology

[0004] (1) Low tensile strength: At present, the tensile strength of commercial magnesium alloys is less than 280MPa, especially the high-temperature mechanical properties are poor. When the temperature rises, its strength and creep resistance will drop significantly, which limits its structure, Applications in load-bearing and other fields;

[0005] (2) Poor toughness: At present, the elongation of commercial magnesium alloys is generally less than 10%, which limits its processing and forming properties

If the strength is increased, the elongation will be greatly reduced. For example, the highest strength ZK61 magnesium alloy, although its strength can reach 275-305MPa, its elongation is only 4-7%;

[0006] (3) High chemical activity, easy to oxidize and burn: it will burn at 350°C, and it is difficult to heat-process and shape;

[0007] (4) Poor corrosion resistance: the substrate is easily oxidized in the air: generally, the surface of the substrate will oxidize and turn gray to black in 3-5 days