Atomic study of hydrogen behaviors at∑3(111)grain boundary in equiatomic CoCrNi and CoCrNiFe alloys

作     者：Hua-Qing Guan Yan-Mei Jing Shao-Song Huang 

作者机构：Key Laboratory of Material Modification by LaserIon and Electron Beams(Dalian University of Technology)Ministry of EducationDalian116024China 

出 版 物：《Tungsten》 (钨科技（英文）)

年 卷 期：2022年第4卷第3期

页      面：239-247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] 0827[工学-核科学与技术] 082701[工学-核能科学与工程] 0703[理学-化学] 0702[理学-物理学] 

基　　金：This research was supported by the National Natural Science Foundation of China under the number of 12075044. 

主　　题：Hydrogen embrittlement Grain boundary DFT High-entropy alloy 

摘      要：High-entropy alloys are potential advanced structural materials for applications in nuclear energy due to their proved high irradiation performance.However,exposing components made of structure materials to service conditions under certain nuclear environments may induce hydrogen embrittlement(HE)as one of the typical failure mechanisms.In this work,we performed density functional theory(DFT)calculations to examine the role of specific element species in HE mechanism in CoCrNi and CoCrNiFe alloys.The solution energy,binding energy and diffusion barrier of H atoms at∑3 GBs(GBs is short for grain boundaries)are presented.Based on the DFT data,we found that Cr limits the H atom to a specific potential position,thus suppresses H segregation.The dipole moment interaction between H and Fe atoms weakens the binding of H atoms.The lattice distortion effect-induced trapping for H provides higher H diffusion barriers at∑3 GBs than that in pure Ni.