Diffusion behavior at void tip and its contributions to void shrinkage during solid-state bonding

作     者：C.Zhang M.Q.Li H.Li 

作者机构：School of Materials Science and EngineeringNorthwestern Polytechnical University State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical University Department of Mechanical EngineeringUniversity de Lyon 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2018年第34卷第8期

页      面：1449-1454页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 09[农学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos.51505386 and 51275416) the Fundamental Research funds for the Central Universities (No.3102017GX06003) 

主　　题：Stainless steel Micro-void morphology Solid-state bonding Void tip Element diffusion 

摘      要：Solid-state diffusion bonding is an advanced joining technique, which has been widely used to join similar or dissimilar materials. Generally, it is easy to observe the diffusion behavior during dissimilar bonding, but for similar bonding the diffusion behavior has yet been observed via experiments. In this study, the diffusion behavior at void tip was firstly observed during similar bonding of stainless steel. Scanning electron microscopy with energy dispersive spectroscopy was used to examine the interface charac- teristic and diffusion behavior. The results showed that a diffusion region was discovered at void tip. Element concentrations of diffusion region were more than those of void region, but less than those of bonded region. This behavior indicated that the diffusion was ongoing at void tip, but the perfect bond has yet formed. The diffusion region was attributed to the interface diffusion from adjacent region to void tip due to the stress gradient along bonding interface. The mass accumulation at void tip transformed the sharp void tip into smooth one at the beginning of void shrinkage, and then resulted in shorter voids.