Residual Stress Analysis Due to Chemomechanical Coupled Effect, Intrinsic Strain and Creep Deformation During Oxidation

Abstract

Metal oxidation at high temperature is often accompanied with the stress generation both in the metal substrate and the growing oxide scale. In this paper, taking into account the growth strain, intrinsic strain and creep deformation, a new analysis model to characterize the residual stress evolutions during an isothermal oxidation process is developed on the basis of the mechanical-balance and moment-equilibrium equations. In this model, the growth strain and the stress are coupled based on an evolving equation, which reduces to the Clarke’s assumption if the stress influence on the growth strain of the oxide scale is ignored. The curvature describing the bending of the system is expressed. Euler numerical method is adopted to simulate the stress evolution and the comparisons among the present model, Zhang’s creep solution and the experimental results are also performed. Finally, effects of creep constants, substrate thickness and intrinsic strain on the residual stress distribution in the oxide scale/metal substrate are discussed.