Wrought magnesium alloys in high intensity, high plasticity, and preparation method

Abstract

This invention discloses a method for preparing Mg alloy with high strength and high plastic deformation. The compositions of the Mg alloy are: Zn 4.5-5.5 wt.%, Ce 0.5-2.5 wt.%, Ti 0.01-0.20 wt.%, Si less than or equal to 0.08 wt.%, Fe less than or equal to 0.01 wt.%, Cu less than or equal to 0.01 wt.%, Ni less than or equal to 0.002 wt.%, impurities less than or equal to 0.05 wt.%, and Mg as balance. The method adds rare earth element Ce to Mg-Zn-Zr alloy, and replaces Zr with Ti, thus can refine the alloy grains. Besides, Mg forms a dispersed reinforcing phase, which can effectively improve the comprehensive properties of the Mg alloy. The surface quality of the extruded product of the Mg alloy is obviously improved when compared with ZK series deformed Mg alloys. The average tensile strength, yield strength and elongation at breakage of the Mg alloy at room temperature are 360 MPa, 245 MPa and 7%, respectively. The average tensile strength and elongation at breakage of the Mg alloy at 150 deg.C are 250 MPa and 11%, respectively.

Description

technical field [0001] The invention belongs to the technical field of magnesium alloy production, in particular to a deformed magnesium alloy with high strength and high plasticity. Background technique [0002] At present, the poor plasticity of high-strength deformation materials of magnesium-zinc-zirconium alloys (such as ZK60 magnesium alloys) makes it difficult to control the hot extrusion process conditions. The deformation temperature is too low to fully activate all the slip systems of the magnesium matrix, and the second phase of the alloy hinders the deformation significantly, and the phenomenon of "squeezing" appears. Because the melting point of zinc is low, it can be found in the alloy structure that the eutectic composition segregation between dendrite arms is relatively serious. Therefore, if the deformation temperature is too high, the alloy is prone to overheating and overburning during hot processing, and the surface quality of the extruded material is poo...

AI Technical Summary

Problems solved by technology

[0002] At present, the poor plasticity of high-strength deformation materials of magnesium-zinc-zirconium alloys (such as ZK60 magnesium alloys) makes it difficult to control the hot extrusion process conditions

The deformation temperature is too low to fully activate all the slip systems of the magnesium matrix, and the second phase of the alloy hinders the deformation significantly, and the phenomenon of "squeezing" appears

Because the melting point of zinc is low, it can be found in the alloy structure that the eutectic composition segregation between the dendrite arms is relatively serious, so the deformation temperature is too high, the alloy is prone to overheating and overburning during hot processing, and the surface quality of the extruded material is poor.