Abstract
The stress fields induced by a dislocation and its image dislocations around a narrow elliptic void are formulated. Based on the solution, the stress distribution and effective stress intensity factor of a blunt (elliptic) crack were calculated under mode I constant loading. The results show that a dislocation-free zone (DFZ) is formed after dislocation emission. There exists a second stress peak in the DFZ except a stress peak at the blunt crack tip. With an increase in the applied stress intensity factorK la or the friction stress τf of the material, the DFZ size and the peak stress at the crack tip decrease, but the peak stress in the DFZ and the effective stress intensity factorK if presiding at the crack tip increase. Because of dislocation shíeldíing, effects, shieldíng ratioK la/K if increases with increasingK la, but it decreases with increasing τf.
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Qian, C., Qiao, L. & Chu, Q. Stress distribution and effective stress intensity factor of a blunt crack after dislocation emission. Sci. China Ser. E-Technol. Sci. 43, 421–429 (2000). https://doi.org/10.1007/BF02916990
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DOI: https://doi.org/10.1007/BF02916990