Design of experiments in thermal spraying: A review

The designs of experiments (DOE) methodology useful for thermal spraying and associated processes of post-spray treatment are thoroughly reviewed. The designs Hadamard (Plackett–Burman), two-level full and fractional factorial and also the response surfaces methodology are briefly described. The designs enable to obtain a polynomial regression equation which expresses the influence of process parameters on the response. The methods of determining of the significant coefficients of the regression equation (factors) are discussed. Examples of the application of different designs to determine the response equations with the responses related to microstructure, mechanical, electrical and other properties of coatings deposited using different thermal spray and post-spray processes are presented and discussed.