(上海交通大学金属基复合材料国家重点实验室,上海 200030)
摘 要: 从热力学角度分析了SiC晶须与Mg-Li-Al合金的化学相容性,利用透射电镜及高分辨电镜研究了SiCw/MgLiAl复合材料的界面结构,并测试了复合材料的力学性能。结果表明,该复合体系化学相容性较好, SiC晶须与基体合金界面结合紧密,没有反应物;少数SiC 晶须表面发生了沿{111}晶面的定向损伤,出现了70.5°或109.5°台阶。拉伸实验结果表明,SiC晶须对Mg-Li-Al合金具有明显的强化作用,使复合材料的抗拉强度、弹性模量明显提高。
关键字: SiCw/MgLiAl复合材料;界面结构;力学性能
(State Key Lab of MMCs, Shanghai Jiao Tong University, Shanghai 200030, P.R.China)
Abstract:The chemical compatibility, interfacial structure and tensile properties of SiCw/MgLiAl composites were studied. The results showed that the thermodynamic potential for the reaction between the matrix and SiC whiskers is very low. There is a good connection between the Mg-Li-Al matrix and SiC whiskers. No compound was found on the interface of the composites. However, some whiskers were invaded in the direction {111}. As a result, stages with 70.5° or 109.5° angles were formed on the surface of SiC whiskers. Tensile test confirmed that the tensile strength of SiCw/MgLi8Al1 composites was increased by nearly 50%, in compared with the matrix alloy.
Key words: SiCw/MgLiAl composites; interfacial structure; mechanical properties