Discussion on “A Mixed Mode Crack Growth Model Taking Account of Fracture Surface Contact and Friction” by Bian Et al. (2006)

A mixed-mode fatigue crack growth model with taking account of fracture surface contact and friction was developed recently by Bian et al. (2006), in reference to the general three-dimensional tensile stress solution for an elastic elliptical crack that was given by Kassir and Sih (1975). However, this general stress solution contains an error, and thus all equations for the fatigue crack growth model proposed by Bian et al. (2006) involve the error. The correct three-dimensional stress field for the elastic elliptical crack is then presented, and three fatigue crack growth models are corrected and expressed as simple functions in this paper.