Molecular dynamics simulations of hcp/fcc nucleation and growth in bcc iron driven by uniaxial compression

作者：Wang B T^*; Shao J L; Zhang G C; Li W D; Zhang P

来源：Journal of Physics: Condensed Matter , 2009, 21(49): 495702.

DOI：10.1088/0953-8984/21/49/495702

Molecular dynamics simulations have been performed to study the structural transition in bcc iron under uniaxial strain loading. We found that the transition pressures are less dependent on the crystal orientations, similar to 14 GPa for [ 001], [ 011], and [ 111] loadings. However, the pressure interval of a mixed phase for [ 011] loading is much shorter than loading along other orientations. In addition, the temperature increased amplitude for [ 001] loading is evidently lower than other orientations. The nucleation and growth of the hcp/fcc phases, and their crystal orientation dependence, were analyzed in detail, where the atom structure was presented by the topological medium-range-order analysis. For [ 001] compression, the hcp structure occurs first and grows into a laminar morphology in the ( 011)(bcc) plane with some fcc atoms as an intermediate structure. For loading along [ 011] and [ 111] directions, both hcp and fcc structure nucleation and growth along the {110}(bcc) planes are observed; their morphology is also discussed.

• 出版日期2009-12-9
• 单位北京大学; 北京应用物理与计算数学研究所; 山西大学