WE43稀土镁合金板材热塑性变形行为研究  

Study on Thermoplastic Deformation Behavior of WE43 Rare Earth Magnesium Alloy Plate

作　　者：陶延夏 朱新亚 何建丽[1] TAO Yanxia;ZHU Xinya;HE Jianli(School of Materials Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)

机构地区：[1]上海工程技术大学材料工程学院,上海201620

出　　处：《热处理》2022年第5期19-24,共6页Heat Treatment

基　　金：国家自然科学基金资助项目(51805313)。

摘　　要：通过在150~450℃以0.01 s^(-1)和0.1 s^(-1)的应变速率采用Gleeble-3800热模拟试验机进行的拉伸试验,测定了10 mm厚WE43稀土镁合金板的拉伸性能。检测了拉伸试验后试样的显微组织和断口形貌以及板的原始晶粒尺寸,绘制了拉伸试验的真应力-真应变曲线。结果表明:WE43镁合金板的热塑性变形行为在250~350℃发生临界转变;在≤250℃的低温,WE43镁合金板的热塑性变形行为对温度和应变速率极不敏感,真应力-真应变曲线无明显软化阶段,达到峰值应力后试样断裂,以韧性断裂为主,脆性断裂为次;在高于250℃的较高温度,WE43稀土镁合金板的热塑性变形行为对温度和应变速率敏感,随着拉伸试验温度的升高,以相同应变速率拉伸试验时峰值应力急剧减小,材料内形成了少量孪晶,热塑性变形以滑移为主,拉伸试样为韧性断裂。Tensile properties of WE43 rare earth magnesium alloy plate of 10 mm thickness were measured by tensile test which was done at temperatures of 150 to 450℃at strain rates of 0.01 and 0.1 s^(-1)via a Gleeble-3800 thermal simulation tester.The microstructure and fracture pattern of the tensile specimens after tensile tests and the original grain size of the plate were detected.The true stress-true strain curves during the tensile tests were plotted.The results showed that(a)thermoplastic deformation behavior of WE43 rare earth magnesium alloy plate underwent critical transformation at temperatures of 250 to 350℃;(b)at low temperatures equal to or higher than 250℃,the thermoplastic deformation behavior of WE43 magnesium alloy plate was extremely insensitive to both temperature and strain rate,the true stress-true strain curve had no obvious softening stage,and after reaching the peak stress the specimen fractured,involving main ductile fracture and secondary brittle fracture;and(c)at higher temperatures above 250℃,the thermoplastic deformation behavior of WE43 magnesium alloy plate was sensitive to both temperature and strain rate,as the tensile test temperature increased,the peak stress decreased sharply during tensile test at the same strain rate,a small number of twins formed in the material,the thermoplastic deformation was dominantly slip,and the tensile specimen was ductile fracture.

关 键 词：WE43镁合金 热塑性变形为 微观组织 拉伸试验 

分 类 号：TG146[一般工业技术—材料科学与工程]