Intrinsic mechanical behavior of MgAgSb thermoelectric material:An ab initio study

作     者：Guodong Li Qi An Umut Aydemir Sergey I.Morozov Bo Duan Pengcheng Zhai Qingjie Zhang William A.Goddard Ⅲ 

作者机构：Hubei Key Laboratory of Theory and Application of Advanced Materials MechanicsSchool of ScienceWuhan University of TechnologyWuhan430070China State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan430070China Department of Chemical and Materials EngineeringUniversity of Nevada RenoRenoNV89557USA Department of ChemistryKoc UniversitySariyerIstanbul34450Turkey Boron and Advanced Materials Research CenterKoc UniversitySariyerIstanbul34450Turkey Department of Computer Simulation and NanotechnologySouth Ural State UniversityChelyabinsk454080Russia Materials and Process Simulation CenterCalifornia Institute of TechnologyPasadenaCA91125USA 

出 版 物：《Journal of Materiomics》 (无机材料学学报（英文）)

年 卷 期：2020年第6卷第1期

页      面：24-32页

核心收录：

学科分类：0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 070205[理学-凝聚态物理] 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] 0702[理学-物理学] 

基　　金：partially supported by the NSFC(No.51972253) Fundamental Research Funds for the Central Universities(WUT:2019IVA055,2019IB006,2019III208) the support by Act 211 Government of the Russian Federation,under No.02.A03.21.0011 by the Supercomputer Simulation Laboratory of South Ural State University 

主　　题：MgAgSb thermoelectric materials Density functional theory Ideal strength Deformation mechanism 

摘      要：α-MgAgSb based thermoelectric(TE)device attracts much attention for its commercial application because it shows an extremely high conversion efficiency of ~8.5% under a temperature difference of 225 ***,the mechanical behavior of α-MgAgSb is another serious consideration for its engineering ***,we apply density functional theory(DFT)simulations to examine the intrinsic mechanical properties of all three MgAgSb phases,including elastic properties,shear-stress-shear-strain relationships,deformation and failure mechanism under ideal shear and biaxial shear *** find that the ideal shear strength of α-MgAgSb is 3.25 GPa along the most plausible(100)slip *** strength is higher than that of β-MgAgSb(0.80 GPa)and lower than that of γ-MgAgSb(3.43 GPa).The failure of α-MgAgSb arises from the stretching and breakage of MgeSb bond α-MgAgSb under pure shear load,while it arises from the softening of MgeAg bond and the breakage of AgeSb bond under biaxial shear *** suggests that the deformation mechanism changes significantly under different loading conditions.