预制孪晶对AZ31镁合金绝热剪切敏感性的影响  

Influence of pre-twinning on adiabatic shear sensitivity of AZ31 magnesium alloy

作　　者：毛萍莉[1] 杨雨松 MAO Pingli;YANG Yusong(School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110870,Liaoning,China)

机构地区：[1]沈阳工业大学材料科学与工程学院,辽宁沈阳110870

出　　处：《沈阳工业大学学报》2024年第3期277-283,共7页Journal of Shenyang University of Technology

基　　金：辽宁省高水平创新团队项目(XLYC1908006);辽宁省教育厅项目(LZGD2020003)。

摘　　要：为了分析不同孪晶体积分数对材料绝热剪切敏感性的影响,预制具有不同孪晶体积分数的AZ31镁合金。采用分离式霍普金森压杆在200℃、944 s^(-1)条件下对AZ31镁合金帽状试样进行高速冲击试验,采用电子背散射衍射仪和光学显微镜对试样在高应变速率变形前后的微观组织进行观察,计算了试样发生绝热剪切时的吸收能量,比较了绝热剪切带内外的显微硬度。结果表明:不同孪晶体积分数试样内均产生了绝热剪切带,随着孪晶体积分数的增加,绝热剪切带宽度和吸收能量减小,而绝热剪切敏感性增大。In order to study the effect of different twin volume fractions on the adiabatic shear sensitivity of materials,AZ31 magnesium alloys with different twin volume fractions were obtained by pre-compression.The hat-shaped samples were subjected to high speed impact at the temperature of 200 ℃ and the strain rate of 944 s^(-1) by using split Hopkinson pressure bar(SHPB).The microstructure evolution before and after high strain rate deformation was characterized by electron backscatter diffractometer(EBSD) and optical microscope(OM).The absorbed energy of samples during adiabatic shear process was calculated,and the micro-hardness within and without the adiabatic shear band(ASB)was tested.The results show that the adiabatic shear band can be found in samples with different twin volume fractions.With the increase of twin volume fraction,the width and absorb energy of the adiabatic shear band decrease,while the adiabatic shear sensitivity increases.

关 键 词：AZ31镁合金 预制孪晶 高速冲击 帽状试样 吸收功 显微硬度 绝热剪切带 绝热剪切敏感性 

分 类 号：TG146.2[一般工业技术—材料科学与工程]