DYNAMIC RESPONSE FOR FUNCTIONALLY GRADED MATERIALS WITH PENNY-SHAPED CRACKS

This paper provides a method for studying the penny-shaped cracks configuration infunctionally graded material(FGM) structures subjected to dynamic or steady loading.It is assumedthat the FGMs are transversely isotropic and all the material properties only depend on the axial coordi-nate z.In the analysis,the elastic region is treated as a number of layers.The material properties aretaken to be constants for each layer.By utilizing the Laplace transform and Hankel transform tech-nique,the general solutions for the layers are derived.The dual integral equations are then obtained byintroducing the mechanical boundary and layer interface conditions via the flexibility/stiffness matrixapproach.The stress intensity factors are computed by solving dual integral equations numerically inLaplace transform domain.The solution in time domain is obtained by utilizing numerical Laplace in-verse.The main advantage of the present model is its ability for treating multiple crack configurationsin FGMs with arbitrarily distributed and continuously varied material properties by dividing the FGMsinto a number of layers with the properties of each layer slightly different from one another.