Sn对汽车用Mg-8Al-0.5Ca镁合金热轧组织和力学性能的影响  

Effect of Sn on Microstructure and Mechanical Properties of Hot Rolled Mg-8Al-0.5Ca Magnesium Alloy for Automobile

作　　者：董彬[1] 刘兴亚[2] 田勇[3] 

机构地区：[1]黄河科技学院交通学院,河南焦作454950 [2]郑州信息科技职业学院,河南郑州450000 [3]河南工业大学机电工程学院,河南洛阳471023

出　　处：《热加工工艺》2017年第17期81-83,89,共4页Hot Working Technology

摘　　要：通过SEM、XRD和拉伸试验机研究了不同Sn含量下Mg-8Al-0.5Ca-x Sn镁合金棒材的微观组织以及力学性能。结果表明:加入Sn的镁合金热轧后晶粒细化,随着Sn元素的增加,平均晶粒直径逐步减小。热轧后镁合金组织中的相主要有α-Mg相和β-Mg_(17)Al_(12)相,Mg2Sn相随着Sn的增多明显增加。镁合金中颗粒状的β-Mg_(17)Al_(12)相与Mg_2Sn相分布于晶界处。随着Sn含量的增加,镁合金的极限抗拉强度,屈服强度和硬度增加,伸长率稍微降低。镁合金含有大量韧窝以及少量撕裂棱,呈现微孔聚集性断裂特征。The microstructure and mechanical properties of Mg-8Al-0.5Ca-xSn magnesium alloy bars with different Sn contents were studied by SEM, XRD and tensile testing machine. The results show that grains of hot-rolled magnesium alloy with Sn are refined, and the average grain diameter decreases gradually with the increase of Sn. The microstructure of hot-rolled magnesium alloy is mainly α-Mg and β-Mg17Al12 phases, and Mg2Sn phase increases obviously with the increase of Sn. Granular β-Mg17Al12 and Mg2Sn phases distribute in the grain boundary. With the increase of Sn content, the magnesium alloy ultimate tensile strength, yield strength and hardness increase, and the elongation slightly reduces. Magnesium alloy contains a large number of dimples and a small amount of tearing edgesq showing the characteristics of micro-porous aggregation fracture.

关 键 词：镁合金 Sn元素 微观组织 力学性能 

分 类 号：TG339[金属学及工艺—金属压力加工]