Jang J H, Moon J, Ha H-Y, Lee T-H, Suh D-W
Ferrous Alloy Department, Korea Institute of Materials Science, Changwon, 51508, Republic of Korea.
Graduate Institute of Ferrous Technology, POSTECH, Pohang, 37673, Republic of Korea.
Sci Rep. 2017 Dec 19;7(1):17860. doi: 10.1038/s41598-017-18230-z.
With regard to the transformation mechanism of austenitic high manganese steel, the prediction of the ε-martensite start temperature is a critical consideration in alloy design. Evaluation of the ε-martensite start temperature makes it possible to predict the microstructure and to understand the phase transformation occurring during deformation. Here we use the quantum mechanical calculation of random alloys to understand the physics for ε-martensitic transformation in steels. We could find the linear relationship between the measured ε-martensite start temperatures and the crystal structure stability for various compositions. We also could estimate the effect of several alloying elements. It is expected that the effect of decreasing the temperatures for the same amount of alloying elements addition will be larger moving farther from Group VIII. By creating a free-energy model that reflects the temperature effect, we were able to calculate the average driving force required for the ε-martensitic transformations.
关于奥氏体高锰钢的相变机制，ε-马氏体开始温度的预测是合金设计中的关键考量因素。对ε-马氏体开始温度的评估使得预测微观结构以及理解变形过程中发生的相变成为可能。在此，我们利用随机合金的量子力学计算来理解钢中ε-马氏体相变的物理原理。我们能够找到不同成分下测量得到的ε-马氏体开始温度与晶体结构稳定性之间的线性关系。我们还能够估算几种合金元素的影响。预计对于相同数量的合金元素添加，远离第八族时降低温度的效果会更大。通过创建反映温度效应的自由能模型，我们能够计算ε-马氏体相变所需的平均驱动力。
