Crack Tip Dislocation Nucleation in FCC Solids
- Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena, California 91125 (United States)
- Department of Mechanical and Aerospace Engineering, Arizona State University, Tempe, Arizona 85287-6106 (United States)
We present results of molecular dynamic simulations aimed at examining crack tip dislocation emission in fcc solids. The results are analyzed in terms of recent continuum formulations of this problem. In mode II, Au, Pd, and Pt displayed a new unanticipated mechanism of crack tip dislocation emission involving the creation of a pair of Shockley partials on a slip plane one plane below the crack plane. In mode I, for all the materials examined, Rice{close_quote}s continuum formulation [J.thinspthinspMech.thinspthinspPhys.thinspthinspSolids {bold 40}, 239 (1992)] underestimated the stress intensity for dislocation emission by almost a factor of 2. Surface stress corrections to the emission criterion brought the agreement between continuum predictions and simulations to within 20{percent}. {copyright} {ital 1999} {ital The American Physical Society}
- DOE Contract Number:
- FG03-94ER45524
- OSTI ID:
- 679219
- Journal Information:
- Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 8 Vol. 82; ISSN 0031-9007; ISSN PRLTAO
- Country of Publication:
- United States
- Language:
- English
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