APPLICATION OF THE DOUBLE SLIP PLANE CRACK MODEL TO TEMPERATURE AND STRAIN RATE SENSITIVE BCC METALS

Abstract

The double slip plane crack model proposed by Weertman, Lin and Thomson (1982) has been applied to model the effect of temperature and strain rate on the stress intensity factor at a crack tip in temperature and strain rate sensitive materials. Increase in temperature or decrease in strain rate (as well as a decrease in slip plane spacing) are shown to increase the shielding of the crack tip by dislocation distributions on the slip planes. Furthermore, the effect of temperature on the fracture toughness, K(IIc), at various strain rates was shown to exhibit the same sigmoidal shaped curve seen for K(Ic) data in typical alloy steels.