摘要
通过金相显微测试仪和力学拉伸试验仪器,分析了500～700℃退火温度下车用AZ91D镁合金板材室温拉伸力学性能以及断裂组织。研究结果表明:随着退火温度的增加,合金的晶粒尺寸逐渐增大,材料的抗拉强度降低。伸长率先增大后降低,并且在600℃下达到最大值,500,600与700℃温度下退火得到的试样的平均晶粒尺寸分别为4. 3,8. 5与15. 6μm;随着退火温度的增加,板材拉伸断口附近的显微组织中孪晶组织增加,孔洞变小,在500℃退火得到的镁合金板材断口区域存在一条明显的裂纹;随退火温度的增加,板材拉伸断裂机制为微孔聚集型断裂和解理断裂共同存在的混合型断裂。
Through metallographic microscopy tester and mechanical tensile test instrument,the tensile mechanical properties at room temperature and fracture structures of AZ91D magnesium alloy plate for car under annealing temperatures of 500-700℃were analyzed.The results show that the grain size of AZ91D magnesium alloy increases gradually and the tensile strength decreases gradually with the increase of annealing temperature.While the elongation increases first and then decreases,and the maximum value is obtained at 600℃.Furthermore,the average grain sizes of sample under annealing temperature of 500,600 and 700℃are 4.3,8.5 and 15.6μm respectively.With the increase of annealing temperature,the twinning structure in the microstructure near the tensile fracture increases,and the hole becomes smaller.The fracture zone of magnesium alloy plate obtained at 500%annealing has an obvious crack,and with the increase of annealing temperature,the tensile fracture mechanism of plate is a mixed fracture with microporous aggregate fracture and cleavage fracture.
作者
王亮军
佘银柱
Wang Liangjun;She Yinzhu(Department of Mechanical Engineering,Taiyuan Institute of Technology,Taiyuan 030008,China)
出处
《锻压技术》
CAS
CSCD
北大核心
2019年第2期155-158,共4页
Forging & Stamping Technology
基金
山西省自然科学基金资助项目(20140321014-02)
