Therrien Félix, Stevanović Vladan
Colorado School of Mines, 1500 Illinois St., Golden, Colorado 80401, USA and National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, USA.
Phys Rev Lett. 2020 Sep 18;125(12):125502. doi: 10.1103/PhysRevLett.125.125502.
We present a unifying description for the martensitic transformation of steel that accounts for important experimentally observable features of the transformation, namely, the Neumann bands, the interfacial (habit) plane between the transformed and untransformed phases and their orientation relationship. It is obtained through a simple geometric minimization of the total distance traveled by all the atoms from the austenite (fcc or γ) phase to the martensite (bcc or α) phase, without the need for any explicit energy minimization. Our description unites previously proposed mechanisms but it does not rely on assumptions and experimental knowledge regarding the shear planes and directions, or external adjustable parameters. We show how the Kurdjumov-Sach orientation relationship between the two phases and the {225}_{γ} habit plane, which have both been extensively reported in experiments, naturally emerge from the distance minimization. We also propose an explanation for the occurrence of a different orientation relationship (Pitsch) in thin films.
我们提出了一种关于钢的马氏体转变的统一描述，该描述考虑了转变过程中重要的可实验观察到的特征，即诺伊曼带、转变相和未转变相之间的界面（惯习）平面及其取向关系。它是通过对所有原子从奥氏体（面心立方或γ）相到马氏体（体心立方或α）相所行进的总距离进行简单的几何最小化而获得的，无需任何明确的能量最小化。我们的描述统一了先前提出的机制，但它不依赖于关于剪切平面和方向的假设以及实验知识，也不依赖于外部可调参数。我们展示了实验中广泛报道的两相之间的库尔久莫夫 - 萨克斯取向关系和{225}_{γ}惯习平面是如何从距离最小化中自然出现的。我们还对薄膜中出现不同取向关系（皮茨）的现象提出了解释。
