HotQC simulation of nanovoid growth under tension in copper
نویسندگان
چکیده
We apply the HotQC method of Kulkarni et al. (J Mech Phys Solids 56:1417–1449, 2008) to the study of quasistatic void growth in copper single crystals at finite temperature under triaxial expansion. The void is strained to 30% deformation at initial temperatures and nominal strain rates ranging from 150 to 600K and from 2.5×105 to 2.5×1011 s−1, respectively. The interatomic potential used in the calculations is Johnson’s Embedded-AtomMethod potential Johnson (Phys Rev B 37:3924–3931, 1988). The computed pressure versus volumetric strain is in close agreement with that obtained using molecular dynamics, which suggests that inertia effects are not dominant for the void size and conditions considered. Upon the attainment of a critical or cavitation strain of the order of 20%, dislocations are abruptly and profusely emitted from the void and the rate of growth of the void M. P. Ariza (B) · M. Ponga Escuela Técnica Superior de Ingeniería, Universidad de Sevilla, Sevilla 41092, Spain e-mail: [email protected] M. Ponga e-mail: [email protected] I. Romero ETSI Industriales, Universidad Politécnica de Madrid, Madrid 28006, Spain e-mail: [email protected] M. Ortiz Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA 91125, USA e-mail: [email protected] increases precipitously. Prior to cavitation, the crystal cools down due to the thermoelastic effect. Following cavitation dislocation emission causes rapid local heating in the vicinity of the void, which in turn sets up a temperature gradient and results in the conduction of heat away from the void. The cavitation pressure is found to be relatively temperature-insensitive at low temperatures and decreases markedly beyond a transition temperature of the order of 250K.
منابع مشابه
HotQC simulation of nanovoid growth under tension in copper M. P. Ariza, I. Romero, M. Ponga & M. Ortiz
We apply the HotQC method of Kulkarni et al. (J Mech Phys Solids 56:1417–1449, 2008) to the study of quasistatic void growth in copper single crystals at finite temperature under triaxial expansion. The void is strained to 30% deformation at initial temperatures and nominal strain rates ranging from 150 to 600K and from 2.5×105 to 2.5×1011 s−1, respectively. The interatomic potential used in th...
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تاریخ انتشار 2012