加工方式对AZ31变形镁合金热拉伸流变应力的影响  

Effect of processing on hot tensile flow stress of AZ31 magnesium alloy at elevated temperature

作　　者：张青来[1] 肖富贵[1] 郭海玲[1] 高霖[2] 王玉华[2] A.B.Bondarev B.I.Bondarev 

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]南京航空航天大学机电工程学院,江苏南京210016 [3]Industrial Center MATEKS Ltd,Moscow 121596,Russia

出　　处：《材料科学与工艺》2010年第1期101-106,共6页Materials Science and Technology

基　　金：国家自然科学基金(50774037);江苏大学资助项目(05JDG009)

摘　　要：针对不同方法制备的AZ31镁合金薄板,利用热拉伸试验机和金相显微镜对其在不同温度和变形速率下的流变应力进行了实验研究.结果表明:挤压、交叉、热轧和冷轧等方法制备的AZ31镁合金薄板的应力-应变曲线基本特征是相同的.峰值流变应力随变形温度的升高和应变速率的降低而降低,在低温时具有明显的厚度效应;当温度大于350℃时峰值流变应力几乎不随板材厚度变化而变化;应变速率小于1.0×10-2s-1,变形温度大于150℃下所有AZ31薄板的延伸率均δ≥45%;单向轧制薄板的各向异性随温度提高减小.Flow stress of different temperature and deformation rate on AZ31B magnesium alloy sheets of different preparation method was studied by tensile test machine and metalloscope. The results show the basic characteristics of stress-strain curves of AZ31 magnesium alloy sheets prepared by extrusion,cross rolling,hot rolling and cold rolling is the same. Peak flow stress reduces with strain rate decreases and deformation temperature increases. There is obvious thickness effect on peak flow stress at low temperature; the peak flow stress is almost no alterative with the sheet thickness changes at the temperature higher than 350 ℃; the elongation of AZ31 magnesium alloy sheet is more than 45% at strain rate less than 1. 0 ×10 -2s -1 and deformation temperature higher than 150 ℃; anisotropy of longitudinal rolling sheet reduces with the temperature increases.

关 键 词：镁合金 热拉伸变形 流变应力 显微组织 

分 类 号：TG146.22[一般工业技术—材料科学与工程]