Effect of Temperature on Creep Stresses in Thick Spherical Vessels Made of Composite Material

Abstract

The steady-state creep in Al–SiCp composite sphere subjected to internal pressure was investigated. The effect of parameter like operating temperature on the stresses and strain rates in the composite sphere was investigated, and it was found that the stresses in the sphere did not have significant variation with varying temperature. But, the tangential strain rates, radial strain rates as well as effective strain rates in the sphere could be reduced to a significant extent by decreasing the operating temperature. The secondary stage creep deformations and creep stress in thick-walled spherical vessels made of functionally graded composites have been obtained in the present study. The spherical pressure vessel chosen for the investigation is subjected to internal and external pressure under the constant temperature field. The material of the vessel is incompressible. The creep behavior of material is governed by threshold stress-based creep law. The study reveals that for linear variation of reinforcement and assumed pressure ratio, the compressive value of radial stress reduces with an increase in pressure ratio from 2 to 5 over the entire radial distance. However, the longitudinal stress remains compressive at the inner radius, and the value becomes tensile for pressure ratio 3, 4 and 5.