Evolution of internal crack in BCC fe under compressive loading

A molecular dynamics model has been developed to investigate the evolution of the internal crack of nano scale during heating or compressive loading in BCC Fe. The initial configuration does not contain any pre-existing dislocations. In the case of heating, temperature shows a significant effect on crack evolution and the critical temperature at which the crack healing becomes possible is 673 K. In the case of compressive loading, the crack can be healed at 40 K at a load- ing rate 0.025 × 1018 Pa·m1/2/s in 6 × 10−12 s. The diffusion of Fe atoms into the crack area results in the healing proc- ess. However, dislocations and voids appear during healing and their positions change continuously.