Stress corrosion cracking(SCC)is an inherently complicated material degradation induced by combinations of material,environment,and stress condition.Influence of stress condition on stress corrosion crack growth has been evaluated using stress intensity factor.The authors reported that the J integral was appropriate for characterization of crack growth by SCC under small-scale yielding through large-scale yielding.The crack growth rate by SCC,however,still showed wide scatter.The aim of this study is to investigate influencing factors on crack growth rate by SCC.In this study,three types of SCC tests,in which the rate of change in stress intensity factor K was varied,were conducted.The crack growth rate was characterized by the equivalent stress intensity factor based on J integral.The crack growth was faster in K-increasing test than in K-constant or K-decreasing tests at the same KJ level.It was concluded that the crack growth rate by SCC was characterized by the equivalent stress intensity factor and its change rate.