Modeling Creep in a Rotating Composite of Variable Thickness

Abstract

Rotating discs made of discontinuously reinforced aluminium matrix composite (DRAMC) are widely used in gas turbines, jet engines, automotive and aerospace braking systems, and are usually operated at relatively higher angular speed and subjected to high temperature/ thermal gradient. Therefore, the prediction of long-term steady state creep deformations is very important for these applications. The steady state creep behavior of a rotating disc having variable profile has been modeled in this thesis. The material of the disc is assumed to be 6061Al-SiCP,W and undergo steady state creep described by Sherbyâ s law. The creep behavior of disc having (i) linearly varying thickness, (ii) hyperbolically varying thickness have been obtained and compared with those obtained for disc having uniform thickness. The volume of all the discs is kept the same. The study revealed that the stress and the strain rates in the disc can be reduced to a great extent by varying the disc profile. The effect of disc profile on the creep behavior is much prominent in anisotropic disc compared to isotropic disc.