Dongbin Wei, Zhengyi Jiang, Jingtao Han
School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, China.
School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, Wollongong, Australia.
DOI: 10.4236/jmp.2012.310197   PDF    HTML     3,544 Downloads   5,493 Views   Citations

Abstract

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 loading rate 0.025 × 1018 Pa·m^1/2/s in 6 × 10^-12 s. The diffusion of Fe atoms into the crack area results in the healing process. However, dislocations and voids appear during healing and their positions change continuously.

Keywords

Internal Crack; Evolution; BCC Fe; Simulation; Compressive Load

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Conflicts of Interest

The authors declare no conflicts of interest.

References

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