Precipitation behavior and properties of extruded 7136 aluminum alloy under different aging treatments

作     者：Huiyan LI Lina JIA Jiangnan HUANG Yue MA Huiyan LI;Lina JIA;Jiangnan HUANG;Yue MA

作者机构：School of Materials Science and EngineeringBeihang UniversityBeijing 100083China 

出 版 物：《Chinese Journal of Aeronautics》 (中国航空学报（英文版）)

年 卷 期：2021年第34卷第2期

页      面：612-619页

核心收录：

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

基　　金：financially supported by National Key Research and Development Program of China (No.2016YFB0300901) 

主　　题：7136 aluminum alloy Electrical conductivity Mechanical properties Microstructure Retrogression and re-aging 

摘      要：In this work, the mechanical properties and electrical conductivity of the extruded 7136 aluminum alloy treated by single-stage aging treatment(T6), retrogression and re-aging treatment(RRA), and multiple retrogression and re-aging treatment have been investigated by means of hardness measurements, electrical conductivity tests and tensile tests. The results have shown that the properties of the 7136 alloy such as hardness, tensile strength and electrical conductivity were sensitive to retrogression time(within 90 min). With prolonging the retrogression time, the tensile strength was enhanced first and then decreased, yet the electrical conductivity was continuously increased. The 60 min-treated alloy performed the highest tensile strength(716 MPa), whereas the 90 min-treated alloy possessed the highest electrical conductivity(33.95%IACS). Compared with the T6-treated alloy, the tensile strength and electrical conductivity were improved by 3.3%and 18.9%, respectively. The electrical conductivity showed an obvious increase with repetitious times of the RRA treatment. After 3 RRA60 treatment, a good combination of tensile strength(705 MPa) and electrical conductivity(33.20%IACS) can be obtained. Compared with the T6 condition, the tensile strength and electrical conductivity were improved by 1.7% and 16.3%, respectively. The mechanism of microstructure evolution under different aging treatments has been discussed in detail.