Dependence of the supersonic propagation of 2-crowdions on the stacking fault energy in FCC metals

Abstract

Recently, much attention has been paid to the study of supersonic 2-crowdions, since they are more efficient in mass transfer in comparison with classical supersonic crowdions. A supersonic 2-crowdion requires less energy for initiation, and with the same energy as a classic crowdion, it travels a larger distance. It has been repeatedly noted that interatomic potentials affect the self-focusing propagation of 2-crowdions. It seems interesting to compare the motion of 2-crowdions in metals with different values of the stacking fault energy (SFE), since the difference in the SFE energy is one of the evidences of the difference in interatomic potentials. This paper compares the dynamics of supersonic 2-crowdions in three fcc metals, copper, nickel and aluminum, which have low, intermediate, and high SFEs, respectively. It is shown that at the same initial velocity of atoms, supersonic 2-crowdions propagate further in a metal with a lower SFE.