Creep modeling in functionally graded rotating disc of variable thickness

Creep behavior of rotating discs made of functionally graded materials with linearly varying thickness has been investigated. The discs under investigation are made of composite containing silicon carbide particles in a matrix of pure aluminum. The creep behavior of the composite has been described by threshold stress based creep law by assuming a stress exponent of 5. The effect of imposing linear particle gradient on the distribution of stresses and strain rates in the composite disc has been investigated. The study indicates that with increase in particle gradient in the disc, the radial stress increases throughout the disc, whereas the tangential and effective stresses increase near the inner radius but decrease near the outer radius. The steady state strain rates in the composite disc, having gradient in the distribution of reinforcement, are significantly lower than that observed in a disc having uniform distribution of reinforcement.