Microstructures and mechanical properties of a cast Al-Cu-Li alloy during heat treatment procedure  

作　　者：Shu-Wei Duan Kenji Matsuda Tao Wang Yong Zou 

机构地区：[1]MOE Key Laboratory for Liquid-Solid Structure Evolution and Materials Processing,Institute of Materials Joining,Shandong University,Jinan 250061,China [2]Department of Materials Science and Technology,Faculty of Engineering,University of Toyama,Toyama 930-8555,Japan

出　　处：《Rare Metals》2021年第7期1897-1906,共10页稀有金属（英文版）

基　　金：the Key Research and Development Project of Shandong Province(No.2018CXGC0403)。

摘　　要：Al-Cu-Li alloy is a huge potential alloy for aerospace industry due to its low density and excellent comprehensive performances.In this study,the microstructures and mechanical properties of a novel cast Al-Cu-Li alloy during the heat treatment were investigated.Results showed that most of the secondary phases along grain boundaries in as-cast state were dissolved into the Al matrix after homogenization and solution treatment,while the Cu-rich phases were slightly segregated once again on grain boundaries after aging.A relatively good combination of strength and ductility(average ultimate tensile strength of 430 MPa and elongation of 8.9%)was obtained after natural aging.Transmission electron microscopy(TEM)results revealed that there was a complicated precipitate distribution in this cast alloy after natural aging.Compared with the similar alloys which introduced dislocations before aging,the density of T1(Al_(2)CuLi)phases was decreased but the size was increased.The low volume fraction of d0 phase,medium density of needle-shaped precipitates and relativity narrow precipitates-free zone with varying widths near grain boundary are the reasons accounting for the improvement of performances.

关 键 词：Al-Cu-Li alloy Heat treatment MICROSTRUCTURE Mechanical property PRECIPITATE 

分 类 号：TG166.3[金属学及工艺—热处理]