退火处理对AZ31B镁合金组织及力学性能的影响  

Effects of Annealing Process on Microstructure and Mechanical Properties of AZ31B Magnesium Alloy

作　　者：张昕宇 李继军[1] 郎风超[1] 侯小虎[2] 杨诗婷[1] 邢永明[1] ZHANG Xinyu;LI Jijun;LANG Fengchao;HOU Xiaohu;YANG Shiting;XING Yongming(College of Science,Inner Mongolia University of Technology,Hohehot 010051,China;College of Materials and Engineering,Inner Mongolia University of Technology,Hohehot 010051,China)

机构地区：[1]内蒙古工业大学理学院,内蒙古呼和浩特010051 [2]内蒙古工业大学材料科学与工程学院,内蒙古呼和法特010051

出　　处：《热加工工艺》2021年第22期121-124,131,共5页Hot Working Technology

基　　金：国家自然科学基金项目(41961052,11762013,11562016,11762014,12002174);内蒙古自然科学基金项目(2018MS01013);内蒙古工业大学大学生创新实验计划项目(2020093006)。

摘　　要：利用金相显微镜、扫描电镜以及单轴拉伸试验研究了具有双峰晶粒尺寸分布的轧制态AZ31B镁合金退火过程中退火温度及保温时间对再结晶组织和力学性能的影响。结果表明,在150℃退火后静态再结晶发生不完全,保温480 min在室温下沿轧制方向上的抗拉强度可达276 MPa,屈服强度可达176 MPa,提高了镁合金的强度。而在300℃退火后可以改善镁合金的塑性性能。轧制态AZ31B镁合金板材经300℃退火60 min后伸长率最高(27.3%),此时平均晶粒尺寸为9.1μm。在450℃退火后,晶粒发生粗化且晶界粗糙度明显增加。随着退火温度的升高,断裂类型从准解理断裂向韧性断裂转变。Effects of annealing temperature and holding time on the microstructure and mechanical properties of AZ31 B magnesium alloy in rolling state with bimodal grain size distribution were studied by metallographic microscope,scanning electron microscope and uniaxial tensile test.The results show that the static recrystallization occurs incompletely after annealing at 150℃and the tensile strength of the thermal insulation for 480 min along the rolling direction at room temperature can reach 276 MPa,and the yield strength can reach 176 MPa,which improves the strength of magnesium alloy.After annealing at 300℃,the plastic properties of magnesium alloy can be improved.The elongation of rolled AZ31 B magnesium alloy sheet after annealing for 60 min at 300℃is highest(27.3%),at this point,the average grain size is 9.1μm.After annealing at 450℃,grain size coarsens and grain boundary roughness increases obviously.With the increase of annealing temperature,the fracture type changes from quasi-cleavage fracture to ductile fracture.

关 键 词：AZ31B镁合金 退火处理 显微组织 力学性能 断口形貌 

分 类 号：TG166.4[金属学及工艺—热处理]