An Experimental Analysis and Modeling Approach of Response Surface Methodology to Predict the Mass Loss of HVOF Sprayed Coatings

Abstract

The primary failure ways of the hydraulic turbine components, mud pumps and drill pipes are slurry erosion. The cermet coatings produced by HVOF spray method extensively utilized for enhance the slurry erosion performance of the materials. WC-12Co powders were coated on the 35CrMo steel through HVOF were studied in this research. Coatings structures were tested with SEM and XRD techniques, further microhardness, porosity and roughness were estimated. Moreover, the experiments were performed to explore the influence of rotational speed, angle of impingement, slurry concentration and time on the slurry erosion behaviour of the coatings. Empirical relationships were established to estimate the mass loss of coatings through response surface methodology. Four factors five level central composite rotatable design matrix was utilized to reduce the level of experimental conditions. The relationship established can be adequately utilized to estimate the mass loss of coatings at a confidence level of 95%.  The rotational speed was the predominant parameter influencing the mass loss of the coatings followed by angle of impingement, slurry concentration and time.