Fracture Toughness Testing for Sheet Specimens under Mode II Loading

Abstract

A fracture toughness testing method for sheet specimens under Mode II loading is proposed and its validity is investigated. The method makes it possible to conduct Mode II testing in a tensile testing machine on the center cracked specimen and the side edge cracked specimen with the same geometry as that for Mode I testing. In order to evaluate fracture toughness, and expression of the Mode II stress intensity factor K_II under nonuniform shear stress is derived by the finite element analyses. The proposed method is applied to PMMA. The result shows that the angle of crack extension and the fracture toughness as obtained by the proposed method are in good agreement with those by Jones' testing method (compact shear specimen method).