The crystallography of phase transformation is an important issue for studying metallic alloys. Here, we demonstrate an abnormal orientation relation between face-centered cubic (fcc) and hexagonal close-packed (hcp) phases due to the intersection of two ε_hcp-martensite variants in a high manganese steel. The corresponding crystallographic characteristics, including invariant line, habit plane and atomic steps, have been characterized by transmission electron microscopy and the quasi-O-line model. In addition, the models of phase transformation about the intersection are proposed based on transmission mechanisms of dislocations. Our findings enrich the theories of phase transformation and implicate the possibility to fabricate stronger and tougher steel.

相变的晶体学是研究金属合金的重要问题。这里，我们证明面心立方（fcc）和六角密堆积（hcp）相之间的异常取向关系由于两个ε交点_的hcp -martensite在高锰钢变体。相应的晶体学特征，包括不变线，惯性面和原子步长，已通过透射电子显微镜和准O线模型表征。此外，基于位错的传输机制，提出了相交处的相变模型。我们的发现丰富了相变理论，并暗示了制造更坚固的钢的可能性。