High strain-rate crack growth in rate-dependent plastic solids

摘要: Abstract At high crack velocities in metallic materials nearly all plastic strain accumulates at very strain-rates, typically the range 10 3 s −1 to 5 . these rates, dislocation motion is limited by dynamic lattice effects and strain-rate increases approximately linearly with stress. The problem for a growing velocity posed steady-state, small scale yielding elastic/rate-dependent solids. A general expression derived near-tip stress intensity factor terms of remote factor, or equivalently energy release-rate overall release-rate. An approximate calculation strain-rates provides this relation analytical form. Imposition condition that be maintained critical value propagation equation crack. single, nondimensional combination material constants emerges as controlling parameter. Implications are discussed.