Prediction and control of residual stresses in thermal sprayed coatings

An analytical model is developed to predict and control the residual stress distributions in deposited coatings and substrate by thermal spraying. Not only the residual stresses in coatings and substrate during quenching and cooling processes, but also for the first time the residual stress in coatings and substrate arising from spraying impact (i.e. spraying particles impacting coatings and substrate at high speed), as well as the residual stress arising from misfit thermal expanding coefficients of substrate and coatings during the whole deposition process are calculated. The calculated results basically agree with the experiment results. With the theoretical prediction of residual stresses in coatings and substrate, the residual stress distributions in coatings and substrate can be controlled. The present work is of some guiding significance for thermal spraying process.