Atomic scale insights into the rapid crystallization and precipitation behaviors in FeCu binary alloys

HD Xu and HW Bao and Y Li and HZ Bai and F Ma, JOURNAL OF ALLOYS AND COMPOUNDS, 882, 160725 (2021).

DOI: 10.1016/j.jallcom.2021.160725

Molecular dynamics (MD) simulations are employed to probe the crystallization and precipitation behaviors in FeCu alloys. The alloys will undergo liquid phase separation at high temperature, after which alpha-Fe nucleates preferentially, then metastable Cu solid solutions in BCC lattice (epsilon` phase) nucleate and transform into FCC structure (epsilon-Cu) via martensite phase transformation immediately. Reversible order-disorder transformation behavior is observed during time-consuming crystallization process of epsilon-Cu. Interestingly, the epsilon`-Cu with only approximately three atomic layers in thickness exists stably near BCC/FCC alpha/epsilon interface at room temperature, following the Kurdjumov-Sachs (K-S) orientation relationship. The lower nucleation energy and interface energy are the reasons for the existence of abnormal epsilon`-Cu at the interface. It is also found that the composition and cooling rate play key roles on the final phase structure. The alloys can be fully crystallized upon cooling down at a rate of 0.1 K/ps. (c) 2021 Elsevier B.V. All rights reserved.

Return to Publications page