Mechanical enhancement and weakening in Mo_(6)S_(6)nanowire by twisting  

作　　者：徐克 林演文 石桥 付越群 杨毅 张志森 吴建洋 Ke Xu;Yanwen Lin;Qiao Shi;Yuequn Fu;Yi Yang;Zhisen Zhang;Jianyang Wu(Department of Physics,Research Institute for Biomimetics and Soft Matter,Jiujiang Research Institute and Fujian Provincial Key Laboratory for Soft Functional Materials Research,Xiamen University,Xiamen 361005,China;Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology,Jiangnan University,Wuxi 214122,China;NTNU Nanomechanical Laboratory,Norwegian University of Science and Technology,Trondheim 7491,Norway)

机构地区：[1]Department of Physics,Research Institute for Biomimetics and Soft Matter,Jiujiang Research Institute and Fujian Provincial Key Laboratory for Soft Functional Materials Research,Xiamen University,Xiamen 361005,China [2]Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology,Jiangnan University,Wuxi 214122,China [3]NTNU Nanomechanical Laboratory,Norwegian University of Science and Technology,Trondheim 7491,Norway

出　　处：《Chinese Physics B》2023年第4期534-542,共9页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.12172314,11772278,12002350,and 11904300);the Jiangxi Provincial Outstanding Young Talents Program(Grant No.20192BCBL23029);the Fundamental Research Funds for the Central Universities of Xiamen University(Grant Nos.20720210025 and 20720220023);the“111”Project(Grant No.B16029)。

摘　　要：The torsional,bending and tensile mechanical properties of Mo_(6)S_(6)nanowire are examined by molecular dynamics(MD)simulations with a first-principles-based reactive force field(ReaxFF).It is found that Mo_(6)S_(6)nanowire shows unique mechanical properties such as high torsional and bending flexibility,high Young's modulus and strength,and negative Poisson's ratio.The Mo_(6)S_(6)nanowire can be strengthened or weakened via twisting,depending on the twist angle.The Mo_(6)S_(6)nanowire with a slight twist angle shows brittle failure,whereas it with a large twist angle exhibits ductile failure and necking behavior.Twisted Mo_(6)S_(6)nanowires show a crossover in the negative Poisson's ratio at critical strains,that is,Poisson's ratio first decreases but then increases,with a minimum value down to around-0.8 at the strain of 0.01 as the twist angle is 21.0°/nm.The negative Poisson's ratio and the crossover are explained by the bond transform that makes zero angles to the wire cross-section.

关 键 词：Mo_(6)S_(6)nanowire mechanical properties TWISTING negative Poisson's ratio 

分 类 号：TQ136.12[化学工程—无机化工] TB383.1[一般工业技术—材料科学与工程]