J. Mater. Sci. Technol. ›› 2021, Vol. 60: 156-161.DOI: 10.1016/j.jmst.2020.07.003

• Research Article • Previous Articles     Next Articles

Abnormal orientation relation between fcc and hcp structures revealed in a deformed high manganese steel

Pan Xie, Shucheng Shen, Cuilan Wu*(), Jianghua Chen*()   

  1. Center for High Resolution Electron Microscopy, College of Materials Science and Engineering, Hunan University, Changsha 410082, China
  • Received:2020-03-03 Accepted:2020-05-01 Published:2021-01-10 Online:2021-01-22
  • Contact: Cuilan Wu,Jianghua Chen

Abstract:

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 εhcp-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.

Key words: Phase transformation, Invariant line, Habit plane, Interface, High-manganese steels