Experimental Investigation on Microstructure and Segregation of Ultrahigh Strength Al-Zn-Mg-Cu-Zr-Sc-Ni Alloy during Homogenization

作     者：Li Zhenliang Xie Jianxin Chen Wei Zhai Jing Ren Huiping Wang Yufeng 

作者机构：University of Science and Technology Beijing Beijing 100083 China Ningbo Branch of China Academy of Ordnance Science Ningbo 315103 China Inner Mongolia University of Science and Technology Baotou 014010 China 

出 版 物：《稀有金属材料与工程》 (Rare Metal Materials and Engineering)

年 卷 期：2009年第38卷第A03期

页      面：83-87页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Colleges and Universities Scientific Research Fund of Inner Mongolia (NJ06083) 

主　　题：喷射沉积方法 晶粒 合金 热挤压 

摘      要：Ultrahigh strength Al-12Zn-2.4Mg-1.1Cu-0.20Zr-0.30Sc-0.30Ni alloy billets were fabricated by spray deposition method(the Osprey process). The effect of homogenization treatment on the microstructures and tensile properties were investigated by OM, SEM and EDS. The results show that adding small amount of Sc and Zr can greatly refine the grain size of the billet, with the average grain size of 10 μm. Grain-boundary becomes coarser firstly and then thinner under different homogenizing condition and grain coarsening were observed. The solute elements content of Zn inside grains has a peak at 490 ℃ /2 h, and Cu element, which was solved into matrix, can enhance the matrix hardness obviously during homogenization. The suitable homogenizing treatment is 460～490 °C/2 h for the hot extrusion of the studied alloy; after the optimized solid solution and T6 aging, the highest ultimate tensile strength (UTS) is 858 MPa with a ductility of 4.8%.