The effect of electromechanical treatment on structure and wear resistance of the plasma sprayed Ni coating

The principal aim of this study was to evaluate the effect of electromechanical treatment (EMT) on structure and wear resistance of the plasma sprayed coating from Ni powder. The coating was air plasma sprayed on a substrate of low carbon steel, then it was treated using the EMT with different values of current density. The erosion performance of the plasma sprayed Ni coating and the plasma sprayed Ni coating treated by the EMT was ranked basing on the coating volume loss after wear testing. In this study the erodent material was 50 µm alumina and the impact angle was 90°.The coatings microstructures and phase compositions were evaluated via SEM and XRD. The erosion mechanisms of the coatings were compared by analyzing the cross-sectional and top surface microstructures of the treated by the EMT and the untreated plasma sprayed Ni coatings. The wear resistance was associated with the microstructure of these coatings, such as total defects, porosity, and cracks.