Influence of crack velocity thresholds on stabilized nonequilibrium fracture

Abstract

The time dependence for crack extension in stabilizing mechanical energy release rate fields has been analyzed, including the thermodynamic threshold for crack motion. Analyses based on crack velocity relations ignoring the threshold predict cessation of crack motion only at infinite crack lengths, in clear contrast to experimental observations. The new analysis predicts that crack motion will cease at finite crack lengths, in accord with experimental results, and includes the zero threshold result as an asymptotic limit.