应力诱发NiAl单晶马氏体相变的分子动力学模拟

Molecular dynamics simulation of stress-induced martensitic phase transformation in NiAl

利用嵌入原子势(EAM),对NiAl单晶在外应力作用下的动态拉伸过程进行了分子动力学模拟.应力-应变曲线分析以及原子构型分析表明外应力诱发NiAl合金发生了马氏体相变,原子结构由B2相转变为L10相.通过研究原子构型的演化过程,发现马氏体相变是通过多个{110}孪晶面的扩展和湮灭作用来完成的.同时探讨了马氏体相变的微观机理.

Molecular dynamics simulations are utilized to study the deformation process in NiAl under uniaxial tension using embedded atom method（EAM）interatomic potential.Both the tensile stress-strain curve and the atomic configurations are analyzed.The martensitic phase transformation is observed and the initial B2 NiAl transforms to a face-centered cubic ordered phase（L10）.The investigation of atomic configuration evolution indicates that the martensitic phase transformation occurs by the propagation and annihilation of { 110t twinning planes. The nucleation mechanism of stress induced martensile has also been discussed.