The effect of ceramic in combinations of two sigmoid functionally graded rotating disks with variable thickness

Abstract

This paper present the elastic solutions of the disk made of functionally graded material (FGM) with variable thickness subjected to rotating load. The material properties are presented by combination of two sigmoid FGM (S-FGM) and disk thickness profile are assumed to be represented by power law distributions. Aluminum-ceramic-aluminum FG rotated disk is considered. Hollow disks are considered and the solutions for the stresses and displacements are given under appropriate boundary conditions. The results in metal-ceramic-metal FGMs are presented and compared with the known results in the literature. The solutions for S-FGM are compared with that of non FGM, and for variable thickness and for uniform thickness. The effects of the material grading index, n, and the geometry of the disk on the stress and displacement are investigated. It is found that a FG disk with concave thickness profile has smaller stresses and displacements compared with the concave or linear by variable thickness profile. The results in metal-ceramic or ceramic-metal and metal-ceramic-metal FGMs are compared. These results suggest that a rotating FG disk with metal-ceramic-metal can be more efficient than the one with ceramic-metal or metal-ceramic. Key words: Rotating disk, variable thickness, elasticity, sigmoid functionally graded material.