Study On Biaxial Tensile Deformation Behavior Of Pre-deformed Magnesium Alloy

In the process of practical engineering application,most of the structural parts are under complex stress conditions,and simple tensile and compression tests cannot reflect the true force situation of the components.Therefore,this paper studies the mechanical behavior of pre-deformed AZ31 magnesium alloy samples and rare earth magnesium alloy samples under biaxial tensile tests.This paper mainly studies the deformation behavior of pre-deformed AZ31 magnesium alloy samples before and after heat treatment under biaxial tension loading and the biaxial deformation behavior of rare earth magnesium alloy(Mg-2Zn-0.5Gd).The main conclusions are as follows:(1)The biaxial mechanical behavior study of TD3.5% and TD3.5%-RD7%pre-deformed AZ31 magnesium alloy samples shows that the main deformation mechanism of pre-deformed samples is related to the biaxial stress ratio.When the loading ratio of TD3.5% and TD3.5%-RD7% samples is 2:1 and 1:2,the deformation mechanisms are detwining and twinning,respectively.When the stress ratio is 1:1,twinning and detwining compete with each other.(2)The biaxial mechanical behavior study of PR-TD3.5% and PR-TD3.5%-RD7%samples shows that(pre-deformed AZ31 magnesium alloy samples are annealed at 180?+0.5h)when the pre-deformed annealed sample is loaded biaxially,the effect of annealing treatment to hinder the detwining is related to the structure of the twin crystal and the integral number of the twin crystal.(3)The biaxial mechanical behavior study of magnesium rare earth alloy(Mg-2Zn-0.5Gd)shows that the twin volume fraction increases with the increase of TD stress ratio,that is,the contribution of twinning deformation to the plastic deformation process increases with TD The directional force increases gradually.Under biaxial tensile stress,the selection of twin variants follows the SF law,and the validity of this law increases with the increase of TD force,for example,as the TD stress increases,the proportions of the first and second variants gradually increase.The selection of twinning variants is closely related to the biaxial stress ratio.With the increase of the stress ratio,the proportions of V5 and V6 gradually increase.