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In this paper, a functionally graded thick hollow sphere is considered for the analysis of two-dimensional steady state mechanical stress in the radial and circumferential directions under mechanical loading. Modulus of elasticity is varying with continuous nonlinear variation along the radial direction and Poisson’s ratio is kept as constant. The Legendre series and Euler differential equation are used to solve Navier equations. Geometry of the sphere is assumed in spherical coordinate system. Applying mechanical boundary conditions at inner and outer radii, we have carried out the analytical solutions for stresses, strains and displacements. In the numerical example, only internal pressure is varying along circumferential direction and external pressure is kept as zero. Displacements and mechanical stresses are presented graphically and the results are discussed numerically.

In this study, a thick hollow axisymmetric functionally graded (FG) cylinder is investigated for steady-state elastic stresses using an iteration technique and the finite element method. Here, we have considered a functionally graded cylinder tailored with the material property, namely, Young’s modulus, varying in an exponential form from the inner to outer radius of the cylinder. A mathematical formulation for stress analysis of functionally graded cylinder under internal and external pressure conditions is developed using constitutive relations for stress–strain, strain–displacement relations and the equation of equilibrium. The effect of the in-homogeneity parameter on radial displacement, radial and tangential stresses in a functionally graded cylinder made up of a High Carbon Steel (HCS) metal matrix, reinforced with Magnesium Oxide (MgO) ceramic is analyzed. The iterative method implemented is fast and converges to the solution which can be further improved by considering a higher number of iterations. This is depicted graphically by using radial displacement and stresses in a pressurized functionally graded cylinder obtained for the first two iterations. An iterative solution for non-FGM (or homogeneous material) is validated using the finite element method. The mechanical responses of the functionally graded cylinder obtained from the iterative method and the finite element method are then compared and found to be in good agreement. Results are presented in graphical and tabular form along with their interpretations.

The study presents thermo-mechanical analysis of functionally graded (FG) rotating disc whose material properties, namely, Young’s modulus, density and coefficient of thermal expansion in radial direction are tailored from inner to outer radius using power law form. The disc is considered to be under the influence of internal pressure, centrifugal body force and thermal loading of the form linear as well as quadratic. Response of FG disc under linear and quadratic temperature profile subjected to internal pressure as well as centrifugal body force is analysed. An exact solution for stress in radial and tangential directions, under mechanical and thermal loading is presented. Numerical solutions for stresses under internal pressure with uniform thermal loading are obtained using finite element method and its comparison with analytical results is presented graphically. Results for radial displacement, radial stress and tangential stress are depicted graphically and their interpretation has been discussed.

In engineering applications, pure metals are rarely used because the application may require a material with different properties that is hard as well as ductile. The functionally graded materials are the materials obtained from the composition of two or more different materials, different in properties from the constituent material, to enhance the strength of the resultant material. The concept was introduced in Japan during a space plane project in 1984. Since then, a lot of research work has done in this area under various profiles and under various conditions.