Abstract
The chemical stresses developed in a cylindrical sandwich composite during radial boundary layer diffusion have been investigated. The system consists of a thin layer A of circular cross section sandwiched between two semi-infinite outer layers B, with the diffusivity of diffusant in A (DA) being much greater than that in B (DB). Two boundary conditions, the constant surface concentration and the instantaneous surface concentration, were considered. The concentration distributions were obtained by the Bessel-Laplace transform method. The stress functions were solved analytically based on the linear elasticity. Numerical computations were performed to illustrate the effects of the diffusivity ratio (DA=DB) and of the thickness of the central layer A on stress distributions. The results show that the induced stress in layer A increases as the diffusivity ratio, or its thickness, increases, in consistency with the general findings for composites of rectangular geometry. Copyright © 2012 Tech Science Press.