Kinetics of dislocation emission from crack tips and the brittle to ductile transition of cleavage fracture
- Massachusetts Inst. of Technology, Cambridge, MA (United States)
- California Inst. of Technology, Pasadena, CA (United States)
Several activation configurations of dislocation embryos emanating from cleavage crack tips at the verge of propagating have been analyzed in detail by the variational boundary integral method, as central elements of the rate controlling process of nucleation governed fracture transitions from brittle cleavage to tough forms, as in the case for BCC transition metals. The configurations include those on inclined planes, oblique planes and crack tip cleavage ledges. Surface ledge production resistance is found to have a very strong embrittling effect. Only nucleation on oblique planes near a free surface and at crack tip cleavage ledges are found to be energetically feasible to explain brittle-to-ductile transition temperatures in the experimentally observed ranges.
- OSTI ID:
- 400600
- Report Number(s):
- CONF-951155--; ISBN 1-55899-312-6
- Country of Publication:
- United States
- Language:
- English
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