Residual stress in electric arc sprayed coatings for remanufacturing

The residual stresses in different thickness and different annealing temperatures of electric arc sprayed 7Cr13 coatings were investigated.The microstructure, elastic modulus and residual stress of the coatings were characterized by SEM, XRD, nano-indentation tester and XRD residual stress tester.The results show that the residual stress in the coating is increasing with increasing of the coating thickness.Annealing treatment can release the residual tensile stress of the coatings.When the annealing temperature is between 200-300℃, tensile stress can change from tenstle stress to compress stress in the coatings.The elastic modulus of the coatings is increasing with increasing of annealing temperature.Based on the results mentioned above, some advice and methods to spray forming thickness coatings can be given.