Body-centered-cubic to face-centered-cubic phase transformation of iron under compressive loading along [100] direction

Abstract

Phase transformation of iron nanoplate and bulk under compressive loading along [100] direction is investigated by using the molecular dynamic simulation method. The simulation results show that the iron nanoplate undergoes body-centered-cubic to face-centered-cubic phase transformation; while iron bulk undergoes body-centered-cubic to hexagonal close-packed phase transformation. The two different phase transformation modes can be attributed to the free surface-induced stress effect of the nanoplate. By applying additional lateral stress, the iron bulk also transforms into face-centered-cubic phase. Moreover, the body-centered-cubic to face-centered-cubic phase transformation is further studied in term of elastic stability theory; it is found that the theoretical results are consistent with the simulation results very well. Therefore, it can be concluded that body-centered-cubic to face-centered-cubic phase transformation can be realized under both tensile and compressive loading along [100] direction.