A phase-field model for the phase transition between austenite and martensite and twinning between two martensitic variants is presented from our previous theory [1] with the main focus on the influence of interfacial stress which is consistent with the sharp interface limit. Each variant-variant transformation can be represented by only one order parameter. Thus, it allows us to get the analytical solution of interface energy and width. Coupled phase-field and elasticity equations are solved for cubic-to-tetragonal phase transformation in NiAl shape memory alloy. The effects of interfacial stress are studied for martensite-martensite interfaces in detail which was absent in [1]. Additionally, stress and temperature-induced growth of the martensitic phase inside austenite and twining are simulated. Some of the nontrivial experimentally observed microstructures which were reproduced in the simulations [1] are analyzed in detail. It includes tip splitting and bending, and twins crossing. This theory can be extended for electric, reconstructive, and magnetic phase transformations.

根据我们先前的理论[1]，提出了一种奥氏体和马氏体之间的相变以及两个马氏体变体之间孪生的相场模型，其主要关注界面应力的影响，这与尖锐的界面极限相一致。每个变体-变体变换只能由一个阶数参数表示。因此，它使我们能够获得界面能和宽度的解析解。解决了NiAl形状记忆合金中立方相到四方相变的耦合相场和弹性方程。详细研究了马氏体-马氏体界面的界面应力影响，这在[1]中是没有的。另外，模拟了应力和温度引起的奥氏体内部马氏体相的生长和孪生。在模拟中复制了一些非平凡的实验观察到的微观结构[1]。它包括尖端分裂和弯曲以及双胞胎穿越。该理论可以扩展到电，重构和磁相转换。