Dynamic stress intensity factor of a functionally graded material under antiplane shear loading

The dynamic response of a finite crack in an unbounded Functionally Graded Material (FGM) subjected to an antiplane shear loading is studied in this p aper. The variation of the shear modulus of the functionally graded materia l is modeled by a quadratic increase along the direction perpendicular to t he crack surface. The dynamic stress intensity factor is extracted from the asymptotic expansion of the stresses around the crack tip in the Laplace t ransform plane and obtained in the time domain by a numerical Laplace inver sion technique. The influence of graded material property on the dynamic in tensity factor is investigated. It is observed that the magnitude of dynami c stress intensity factor for a finite crack in such a functionally graded material is less than in the homogeneous material with a property identical to that of the FGM crack plane.