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The behavior of screw dislocations dynamically emitted from the tip of a surface crack during loading and unloading

Published online by Cambridge University Press:  03 March 2011

C.C. Huang
Affiliation:
Department of Materials Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
C.C. Yu
Affiliation:
Department of Physics, Chung Yuan Christian University, Chung-Li, Taiwan, Republic of China
Sanboh Lee
Affiliation:
Department of Materials Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China
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Abstract

The behavior of screw dislocations dynamically emitted from the tip of a surface crack during loading and unloading has been investigated using a discrete dislocation model. The critical stress intensity factor at the crack tip for dislocation emission is a function of friction stress, core radius of dislocation, and dislocations near the crack tip. During motion, the velocity of dislocation is assumed to be proportional to the effective shear stress to the third power. The effect of crack length and friction stress on dislocation distributions, plastic zone, and dislocation-free zone during loading and unloading was examined.

Type
Articles
Copyright
Copyright © Materials Research Society 1995

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References

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