A Critical Analysis of Crack Growth in Creep

Abstract

Experimental investigations have been carried out to study the crack growth behavior in creep in a 6061 Al alloy. The crack growth rate is analyzed by the stress intensity factor, reference stress, energy rate line integral C* and modified J integral method and a critical examination is made of the applicability of different procedures. Based on the experimental observations near the crack zone, a new parameter in the form [Δ̇ / (P/P0 )α ], where Δ̇ is the deflection rate, P the applied load and the exponent α and P0 are constants, is proposed to describe the crack growth behavior in ductile materials.