Numerical simulation of residual stress distributions in plasma-sprayed coating on thick wall component

The residual stress distributions in the plasma sprayed coatings on thick wall component were modeled and numerically simulated in finite element method, based on the software package Nastran. The impacts of the coating conditions, including the species of the coating and substrate, i.e. ceramic or metal, on the residual stress were evaluated. The simulated results show that the strongest stress distribution exists at the coating/substrate interface, increasing in the radial direction and peaking at the edges; and that the normal stress in the central area of the substrate decreases with an increase in substrate depth, and linearly distributes in the coating. Various key factors, including the dimensionless equation of radial stress, shear stress, maximum stain and immersion depth of the residual stress in the coating, were determined. The results, calculated with the dimensionless equation, agree fairly well with the simulated ones in all the coating/substrate systems of interest. The influence of various factors, such as the thickness and elastic modulus of the coating, and the radius and modulus of the substrates, on the variations in the residual stress distributions was also tentatively discussed.