Temperature at a propagating crack tip in a viscoplastic material

Rupture processes at a propagating crack tip and the dissipation of mechanical energy in the vicinity of a crack tip can give rise to substantial temperature increases. In this paper we consider the (;transient) time-dependent temperature field. It is shown that under certain conditions. which are discussed in some detail, the adiabatic approximation gives a very acceptable approximation for the near-tip temperature. The adiabatic approximation has been used to calculate the crack tip temperature for a crack that propagates in a viscoplastic material. The mechanical behavior of the material is represented by a model proposed by Bodner and Partom. The Bodner-Partom model accounts for flux of energy into the crack tip as well as for dissipation of mechanical energy in the near-tip region. The temperatures due to both effects have been analyzed. and estimates are presented for the maximum crack tip temperature that may be reached during the crack propagation process.