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 $\gamma$) phase to the martensite (bcc or $\alpha$) 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 $\{225{\}}_{\gamma }$ 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.

中文翻译：

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最小化原子位移是马氏体相变的指导原则

我们为钢的马氏体相变提供了一个统一的描述，该描述解释了相变的重要实验观察特征，即，诺伊曼谱带，相变和未相变之间的界面（习性）平面及其取向关系。它是通过简单地最小化所有原子从奥氏体（fcc或$\gamma$）相到马氏体（bcc或 $\alpha$）阶段，无需任何显着的能量最小化。我们的描述结合了先前提出的机制，但它不依赖于有关剪切平面和方向或外部可调参数的假设和实验知识。我们展示了两个阶段之间的Kurdjumov-Sach取向关系以及$\{225{\}}_{\gamma }$习惯平面已经在实验中得到了广泛的报道，它们自然是从距离最小化中出现的。我们还提出了薄膜中不同取向关系（Pitsch）发生的解释。