D. B. WEI ET AL.
1600
the original crack was.
5. Conclusion
The critical temperature at which nano scale crack heal-
ing of BCC Fe crystal without pre-existing dislocations
becomes possible is 673 K. Temperature has a significant
effect on the evolution of nano scale crack. Healing pro-
ceeds rapidly at 1173 K. Compressive loading can result
in crack healing. Crack is healed completely at 40 K at
loading rate 0.025 × 1018 Pa·m1/2/s in 6 × 10−12 s. Dislo-
cations and voids appear during healing process, and
their positions change continuously. In the case of heat-
ing, the distribution of the defects in the cell is inho-
mogenous in the early stage of healing. This inhomoge-
neity decreases and the quantity of the defects in the
crack area may be reduced with an increase of time. In
the case of compressive loading, most defects aggregate
in the region where the original crack is.
6. Acknowledgements
The authors thank the support of Australia Research
Council (ARC) Discovery Project.
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