Microstructural evolution and delayed hydride cracking of FSW-AZ31 magnesium alloy during SSRT

作     者：曾荣昌 Wolfgang DIETZEL Rudolf ZETTLER 甘为民 孙芯芯 Rong-chang ZENG;Wolfgang DIETZEL;Rudolf ZETTLER;Wei-min GAN;Xin-xin SUN

作者机构：山东科技大学 材料科学与工程学院青岛266590 Institute of Materials Research Helmholtz-Zentrum Geesthacht 

出 版 物：《Transactions of Nonferrous Metals Society of China》 (中国有色金属学报（英文版）)

年 卷 期：2014年第24卷第10期

页      面：3060-3069页

核心收录：

学科分类：080503[工学-材料加工工程] 0806[工学-冶金工程] 08[工学] 0818[工学-地质资源与地质工程] 0815[工学-水利工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0813[工学-建筑学] 0703[理学-化学] 0802[工学-机械工程] 0814[工学-土木工程] 0702[理学-物理学] 080201[工学-机械制造及其自动化] 

主　　题：magnesium alloys stress corrosion cracking friction stir welding texture microstructure 

摘      要：Evolution of microstructure including texture and fractography in a friction-stir welded（FSW） AZ31 magnesium alloy was investigated. The texture was measured using a neutron diffractometer. The microstructure and fractography of stress corrosion cracking（SCC） samples were observed by optical and scanning electron microscopy, respectively. An X-ray diffraction study was carried out on the fractured surfaces of the SCC specimens. The results indicated that a strong basal fiber was formed on the base material, whereas the grains in the stir zone were reoriented with their most basal planes tilted 25 o to the welding direction. Feather-like twins and hydride formed under slow strain rate tensile（SSRT） stress in air and aggressive solutions, respectively. Transgranular cracks propagated and finally failed on the retreating side in the solution. The hydride phase confirmed to sit on the fracture surface demonstrated the delayed hydride cracking（DHC） mechanism of the alloy.