Effects of material inhomogeneity on creep stresses in a functionally graded cylinder with thickness and density variations have been investigated. Analysis is performed by means of transition theory using the concept of generalized strain measure. Analytical solution for an orthotropic cylin-der subjected to pressure and temperature is derived. The results indicate that the effect of material inhomogeneity and nonlinearity of measure is very pronounced. Highly non-homogeneous isotropic material steel with nonlinear measure is safer for the design as compared to orthotropic materials barite and uranium (alpha) as generated circumferential stresses are lower in steel as compared to barite and uranium.
Keywords: creep, orthotropic, functionally graded material, pressure, cylinder, variable thickness, variable density, temperature