论文标题
42CRMO4钢中的对称分解相关断裂
Symmetry Breakdown Related Fracture in 42CrMo4 Steel
论文作者
论文摘要
接受F.C.C.到卑诗省（或B.C.T.）转换通常由24个Kurdjumov-Sachs变体组成，这些变体可以通过三个Bain变换轴进行分类；因此，完整的转换通常在（001）极图中显示3倍对称性。在目前的工作中，基于FEG-SEM/EBSD技术的方向分布函数（ODF）分析，研究了在马氏体起始温度下方的42CRMO4钢仪上的晶体学对称性。结果表明，在相变时，样品在所有（001），（011）和（111）polef的odf中包含6倍对称性。通过理论建模验证的ODF分析表明，在平面应变条件下，裂纹更喜欢通过高对称性强烈抵消的区域传播。研究了高对称性的起源，并解释了对称分解的机理。
Austenite grains that underwent the f.c.c. to b.c.c. (or b.c.t.) transformation are typically composed of 24 Kurdjumov-Sachs variants that can be categorized by three axes of Bain transformations; thus, a complete transformation generally displays 3-fold symmetry in (001) pole figures. In the present work, crystallographic symmetry in 42CrMo4 steel austempered below martensite start temperature was investigated with the help of the orientation distribution function (ODF) analysis based on the FEG-SEM/EBSD technique. It is shown that, upon phase transformations, the specimens contained 6-fold symmetry in all (001), (011), and (111) pole figures of an ODF. The ODF analysis, verified by theoretical modeling, showed that under plane-strain conditions cracks prefer to propagate through areas strongly offset by the high symmetry. The origin of high symmetry was investigated, and the mechanism of the symmetry breakdown was explained.
