Effect of hydrogen on deformation behavior of Alloy 725 revealed by in-situ bi-crystalline micropillar compression test

作     者：Xu Lu Dong Wang Xu Lu;Dong Wang

作者机构：Department of Mechanical and Industrial EngineeringNorwegian University of Science and TechnologyNo-7491TrondheimNorway 

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

年 卷 期：2021年第67卷第8期

页      面：243-253页

核心收录：

学科分类：08[工学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 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：supported under the scope of the COMET program within the K2 Center“Integrated Computational Material,Process and Product Engineering(IC-MPPE)”(Project No 859480) supported by the Austrian Federal Ministries for Climate Action,Environment,Energy,Mobility,Innovation and Technology(BMK)and for Digital and Economic Affairs(BMDW),represented by the Austrian research funding association(FFG),and the federal states of Styria,Upper Austria and Tyrol financial support of the Research Council of Norway through project Hy LINE(294739) The Research Council of Norway for its support to the Norwegian Micro-and Nano-Fabrication Facility,Nor Fab,project number 245963/F50。 

主　　题：Hydrogen Nickel-based alloy Micropillar compression Plastic deformation Grain boundary 

摘      要：Nickel-based Alloy 725 bi-crystalline micropillars with different types of grain boundaries(GBs)were compressed in hydrogen-free and in-situ hydrogen-charged conditions to investigate the hydrogen effect on the deformation behavior of the selected GBs.In the presence of hydrogen,the compressive stresses on the micropillars increase regardless of the GB type.It was proposed that this hydrogen-induced hardening behavior is the synergistic effect of hydrogen-enhanced dislocation multiplication and interactions,the pinning effect of hydrogen on dislocation motion,and hydrogen-enhanced lattice friction.Transmission electron backscatter diffraction(t-EBSD)results demonstrate that both low-angle GBs and high-angle GBs can effectively suppress dislocation transmission through the GBs,resulting in dislocations pile up along the GBs in the hydrogen-charged condition.In contrast,this behavior was not observed in the micropillars with twin boundaries.