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运用ＮｉＡｌ合金的镶嵌原子势，进行了Ｂ２结构ＮｉＡｌ中热诱发马氏体相变的分子动力学模拟，从而研究马氏体形核和长大的微观机理．首先进行了０Ｋ等体积条件下ＮｉＡｌ的相稳定性分析，发现０Ｋ时点阵参数ｃ与ａ之比约为１．３１的ｂｃｔ结构是稳定结构，Ｂ２结构只是一种亚稳结构．在热诱发马氏体相变的模拟过程中，由于ＮｉＡｌ中Ｎｉ原子和Ａｌ原子的振动性质存在着差异，造成了马氏体的不均匀形核．对另两种不同初始构型的系统进行的模拟进一步证实了不均匀形核的存在，并通过计算Ｂ２结构ＮｉＡｌ中Ｎｉ原子和Ａｌ原子的热运动均方位移解释了其原因．模拟中，Ｂ２结构奥氏体经热诱发马氏体相变转变为ｆｃｔＬ１_０结构的马氏体．马氏体在长大过程中内部形成了若干转变孪晶．
The molecular dynamics simulation of heat induced martensitic transformation in B2 structure NiAl was carried out by using the mosaic atomic potential of NiAl alloy to study the microscopic mechanism of nucleation and growth of martensite. Firstly, the phase stability of NiAl under 0K isobserved. It is found that the bct structure with a ratio of c to a of about 1.31 at 0K is a stable structure, and the B2 structure is only a metastable structure. During the simulation of heat-induced martensitic transformation, the heterogeneity of martensite nucleation is caused by the difference in the vibrational properties of Ni atoms and Al atoms in NiAl. Simulations of two other systems with different initial configurations further confirmed the existence of inhomogeneous nucleation and explained the reasons for the mean thermal motion of Ni atoms and Al atoms in the B2 structure NiAl. In the simulation, B2 structure austenite transformed into martensite with fctL1_0 structure by heat-induced martensitic transformation. Martensitic growth in the process of forming a number of internal transformation twin.