Stress analysis of functionally graded isotropic rotaing discs

The closed-form study deals with stress analysis of annular rotating discs made of functionally graded materials (FGMs) subjected to internal and external pressures. The elasticity modulus and density of the discs are assumed to varies radially according to three diverse power law functions, and it is assumed that the material is of constant Poisson's ratio. A gradient parameter n is chosen between - 0.5 and 1.00. When n equals to zero, the disc becomes isotropic disc case. Dimensionless tangential and radial stresses and radial displacements in the rotating discs are depicted in the Fig.s and tabulated in a table. In present study, it is investigated how to change the distributions of the stresses and displacements with the increasing gradient parameter n (with variation of elasticity modulus and density). For a design problems if someone wants a disc which is of a homogenous stress distribution, he should chose either Disc 3 with n=1.00 or Disc I with n=-0.50 for the lowest stress distribution according to the results of this study for the material producer or applicability of production of the materials