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The stress and curvature resulted from temperature fluctuation in thermally sprayed coatings have been widely investigated in previous studies.However,most of them were focused on the elastic deformation range,and the factor induced by phase transformation was not taken into account.In the present study,an elastoplastic model for prediction the thermal residual stresses in thermally sprayed coating was first proposed,based on the concept of a misfit strain caused by differential thermal contraction between substrate and coating during cooling.Subsequently,the affect caused by martensite phase transformation for steel coating materials was taken into account in the elastoplastic model.From a knowledge of processing temperature,material properties and specimen dimensions,residual stress distributions in the coating and substraté can be predicted.Applications of the model for prediction of the twin-wire electric arc sprayed high carbon steel coating was discussed.Based on the analytical model,the stresses distributions of high carbon steel coating prepared with different deposition temperatures (range below and beyond the martensite transformation start temperature) was first investigated.The results showed that if the deposition temperature is lower than the martensite transformation start temperature,a compressive phase transformation stress will initiated,which partly counteracts the total residual stress (tensile).The model was also used to predict the stress distribution of high carbon steel coatings after 800 ℃ annealing and water quenching heat-treatments,respectively.The quenching treatment leads to a high amount of martentsite transformation and resulted in compressive residual stress in the coating with a high magnitude.Additionally,the modeling results for the heat-treated specimens were compared with the experimental data obtained from X-ray residual stress measurement.