Process Optimization of NiCrAlCo-Y2O3 Coating on an Aluminum Substrate by Plasma Spraying

Orthogonal tests of spraying distance,electrical current,primary gas flow rate and secondary gas flow rate were carried in order to obtain an optimized plasma spraying parameters.The influence of spraying process parameters on bonding strength of NiCrAlCo-Y2O3 coating was investigated.And microstructure,microhardness and porosity of the coatings of before and after process optimization were studied.The results show that the electrical current and spraying distance have more effect on the bonding strength of the coating and aluminum substrate.An optimized process is achieved,and the bonding strength of optimized coating is improved to 55.1 MPa.