Ca对超轻Mg-Li-Al合金显微组织和力学性能的影响  

Effects of Ca on the Microstructures and Mechanical Properties of Mg-Li-Al Alloys

作　　者：李红斌[1] 姚广春[1] 吉海宾[1] 刘宜汉[1] 郭志强[1] 

机构地区：[1]东北大学材料与冶金学院,辽宁沈阳110004

出　　处：《铸造》2005年第12期1276-1279,共4页Foundry

基　　金：国家高技术研究发展计划863项目(2001AA335010)。

摘　　要：本试验熔制了Mg-5,9,16%Li-2%Al合金,研究了添加不同Ca含量对合金组织和性能的影响。通过显微观察可知,元素Ca对显微组织中的α相(hcp)和β相(bcc)有细化作用。通过EPMA分析可知,Ca主要富集在晶界处,合金中的晶界网格为Ca和Al的富集物,为Al2Ca化合物。显微组织细化机理可以认为,由于Ca在晶界处的吸附作用极大的抑制了晶粒的长大而使其细化。室温下进行拉伸测试,结果表明,添加1%Ca可以提高合金的强度,却降低合金的塑性,分别是因为元素Ca的细化作用和晶界处Al2Ca具有脆性的原因。Mg-5,9,16%Li-2%Al alloys were made in this study. It is found that Ca addition from 1 to 2% to Mg-Li-Al alloys produced refinement effects on α phase （hcp） and β（bcc） phases by observing the microstructures of alloys. Adding the Ca resulted in the formation of Al2Ca on the grainboundaries. Mechanical tests are carried out at room temperature. The results show that strength rises while elongation worsened after adding 1% element Ca, which is considered as the grain refinement and the presence of Al2Ca phase. It is clarified that the restriction of the grain is due to Ca aggregations on the boundaries.

关 键 词：CA MG-LI-AL合金 晶粒细化 力学性能 

分 类 号：TG113[金属学及工艺—物理冶金]