微量Li、Zn对Al-4.2Cu-1.4Mg合金疲劳性能与微观组织的影响  

Effects of Trace Li and Zn on Fatigue Property and Microstructure of Al-4.2Cu-1.4Mg Alloy

作　　者：杨文玲[1] YANG Wenling(School of Material Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《热加工工艺》2020年第4期62-65,共4页Hot Working Technology

基　　金：国家自然科学基金资助项目(50871123).

摘　　要：通过断裂韧性测试、疲劳裂纹扩展速率测试、金相分析、透射电子显微分析(TEM)等研究了微量Li、Zn对Al-4.2Cu-1.4Mg合金疲劳裂纹扩展速率与微观组织的影响。结果表明,共同添加Li、Zn时能明显提高合金Al-4.2Cu-1.4Mg的断裂韧性,并降低合金的疲劳裂纹扩展速率。当同时添加少量Li和Zn时,少量Li和Zn的共同作用能使合金中的过剩相和弥散相数量、尺寸减小,分布趋向均匀。这是影响该合金疲劳性能和断裂韧性的微观机理。The effects of trace addition of Li and Zn on the fatigue crack growth rate and microstructure of Al-4.2Cu-1.4Mg alloy were studied by fracture toughness test,fatigue crack growth rate test,metallographic analysis and transmission electron microscopy(TEM)observation.The result shows that the fracture toughness improves and the fatigue crack growth rate decreases by the common addition of Li and Zn.The quantity and size of surplus-phase and dispersed phase decrease by the common trace addition of Li and Zn and then distribution is more uniform,which is the main reason that Li and Zn can significantly effect the fatigue property and fracture toughness resistance of the alloy.

关 键 词：Al-4.2Cu-1.4Mg合金 断裂韧性 疲劳裂纹扩展速率 微观组织 

分 类 号：TG146.21[一般工业技术—材料科学与工程]