M Zamani Nejad - Mechanical Engineering Department, Yasouj University
A Rastgoo - Mechanical Engineering Department, University of Tehran
A Hadi - Mechanical Engineering Department, University of Tehran

A semi-analytical iterative method as one of the newest analytical methods is used for the elastic analysis of thick-walled spherical pressure vessels made of functionally graded materials subjected to internal pressure. This method is accurate, fast and has a reasonable order of convergence. It is assumed that material properties except Poisson’s ratio are graded through the thickness direction of the sphere according to an exponential distribution. For different values of inhomogeneity constant, distributions of radial displacement, radial stress, circumferential stress, and von Mises equivalent stress, as a function of radial direction, are obtained. A numerical solution, using finite element method (FEM), is also presented. Good agreement was found between the semi-analytical results and those obtained through FEM. 

Iterative technique, Elastic analysis, Functionally graded material (FGM), Thick sphere, Exponential