Modeling Creep Behavior of Thermally Graded Rotating Disc of Functionally Graded Material

Abstract

An attempt has been made to model steady-state creep for thermally graded rotating disc made of linearly varying functionally graded material. The stress and strain rate distributions have been calculated for the discs rotating at linearly/parabolically decreasing temperatures using threshold stress based creep law and von Mises’ yield criterion. Further, these results are compared with the disc operating at uniform temperature throughout the radial distance. The results are displayed and compared graphically in designer friendly format for the said temperature profiles. The analysis indicates that stress in composite disc operating under thermal gradient slightly increases as compared to disc operating under constant temperature. However, the strain rate developed near the inner radius in the disc rotating at uniform temperature is lower in comparison to disc having linear/parabolic thermal gradations; whereas the disc operating at uniform temperature shows higher strain rate as compared to disc having linear/parabolic thermal gradations near the outer radius. It is observed that for the disc having thermal gradation the steady state creep rates show less deviation as compared to the disc operating under uniform temperature throughout the radial distance.