The interaction of a mode II crack with an inhomogeneity undergoing a stress-free transformation strain

In this investigation, general approximate solutions for the stress intensity factor (SIF) and configuration force (CF) are derived, respectively, based on the Eshelby theory for the interaction between an inhomogeneous inclusion of arbitrary shape undergoing a stress-free transformation strain and plane stress mode II crack. For common inclusion shapes, some simplified approximate formulae are also developed. Then, the relationship between the normalized CF and SIF is discussed, as well as the effects of inclusion shape, location, and size on the CF and SIF of a plane stress mode II crack. To give deep insight into the complex three-dimensional interaction between an inclusion undergoing a stress-free transformation strain and a crack, two typical cases of the triaxial stress state are analyzed, and no significant difference occurs among most engineering materials.