  In this paper, the linear free flexural vibration of cracked functionally
graded material plates is studied using the extended finite element method. A
4-noded quadrilateral plate bending element based on field and edge consistency
requirement with 20 degrees of freedom per element is used for this study. The
natural frequencies and mode shapes of simply supported and clamped square and
rectangular plates are computed as a function of gradient index, crack length,
crack orientation and crack location. The effect of thickness and influence of
multiple cracks is also studied.
