Study of protective coatings and their optimization using a plasma spray technique

This study reports the use of second-order function on the basis of Taguchi method for plasma-based spray processes to enhance the surface wear resistance of zirconia ceramic coatings. The L18 orthogonal array with eight control factors is used, and the antiwear properties of the deposits are implemented. Small granules are distributed evenly and closely in the fully melted coatings, while surface features show porous structures, cavities, macropores and unmelted zirconium dioxide particles in the partially melted coatings. A dense texture in the coatings is found, which provides good wear resistance, and the polynomial model for the surface wear-resistant properties is constructed. The results of the present study show that the proposed quadratic model, based on orthogonal array design, can obtain the conditions for process optimization and predict wear volume losses to yield desired results. These results provide useful information for the control of wear volume losses for plasma-sprayed coatings and ensure good wear-resistant properties.