Mechanical examination of crack length dependency and material dependency on threshold stress intensity factor range with Dugdale model.

The threshold stress intensity factor range Δ K th was analytically calculated under stress control conditions using the plasticity-induced crack closure analysis with the Dugdale model. Before obtaining Δ K th , the accuracy of the method was verified. The characteristics of the crack closure behavior were discussed by specifying the small-scale yielding (SSY) and large-scale yielding (LSY). The analysis results of Δ K th were discussed systematically by non-dimensionalizing them with the Dugdale model. Under the SSY condition, Δ K th was dependent on Young’s modulus and Poisson’s ratio. Under the LSY condition, Δ K th increased when the initial crack length or yield strain increased. [ABSTRACT FROM AUTHOR]