Subsonic and Intersonic Crack Growth Along a Bimaterial Interface

Abstract

An experimental investigation has been conducted to study the dynamic failure of bimaterial interfaces. Interfacial crack growth is observed using dynamic photoelasticity and characterized in terms of crack-tip velocity, complex stress intensity factor, and energy release rate. On the basis of crack-tip velocity two growth regimes are established, viz. the subsonic and transonic regimes. In the latter regime crack-tip velocities up to 1.3 times the shear wave velocity of the more compliant material are observed. This results in the formation of a line of discontinuity in the stress field surrounding the crack tip and also the presence of a pseudo crack tip that travels with the Rayleigh wave velocity (of the more compliant material).