DYNAMIC-RESPONSE OF A CRACK IN A FUNCTIONALLY GRADED MATERIAL BETWEEN2 DISSIMILAR HALF-PLANES UNDER ANTIPLANE SHEAR IMPACT LOAD

This article provides a theoretical and numerical treatment of a finit e crack subjected to an anti-plane shear impact load in a media with s patially varying elastic properties. This variation is in a direction perpendicular to the crack surfaces. The elastic properties of the int erfacial layer are assumed to vary continuously between that of two di ssimilar homogeneous bonding layers. Laplace and Fourier transforms ar e applied to reduce this mixed boundary value problem to a system of d ual integral equations which in turn will be reduced to a standard Fre dholm integral equation of the second kind. The Fredholm integral equa tion is solved in the Laplace transform plane numerically. The time in version is accomplished by a numerical scheme. The dynamic stress inte nsity factor is found to either increase or decrease with the crack le ngth to the layer thickness depending, on the relative magnitudes of t he material properties of the adjoining layer. (C) 1998 Elsevier Scien ce ltd. All rights reserved.