Analysis of Steady State Creep in Whisker Reinforced Functionally Graded Thick Cylinder Subjected to Internal Pressure by Considering Residual Stress

Abstract

The steady state creep behavior of a functionally graded thick composite cylinder subjected to internal pressure has been analyzed in the presence of residual stress. To study the effect of residual stress, the yielding of composite material is described by Hoffman's yield criterion. The results obtained are compared with a similar cylinder but yielding according to von Mises yield criterion, which ignores the presence of residual stress. The cylinder is made of functionally graded composite containing a linearly varying amount of silicon carbide whisker in a matrix of 6061Al. It is revealed that the presence of residual stress in the FG cylinder having linearly varying whisker content in the radial direction, the radial stress decreases slightly over the entire radius of the cylinder, whereas the tangential and axial stresses increase considerably near the inner radius but show a significant decrease towards the outer radius. In the presence of residual stress, the effective stress also increases in the cylinder, except for some decrease observed near the inner radius. The presence of thermal residual stress in the cylinder leads to increase the tangential as well as radial strain rate throughout the cylinder. The increase observed in strain rate increases with increasing radial distance.

Keywords:

• steady state creep
• cylinder
• functionally graded material
• residual stress