Optimization Parameters of WC-12Co HVOF Sprayed Coatings on SUS 400 Stainless Steel

Abstract

Abstract In this research, the optimization strategy based on statistical design was performed to supplement the mechanical properties (e.g. hardness, porosity, thickness and surface roughness) of HVOF sprayed coatings on SUS 400 stainless steel. The central composite design (CCD) was applied to interpret the variable parameters that significantly influenced the mechanical properties of the specimens. Four important variable parameters were the oxygen flow rate, the propane flow rate, the powder feed rate and the spraying distance which supposed the mechanical properties. Finally, the empirical analysis was used to investigate the optimal condition from which the parameters levels for maximum hardness, minimum porosity, maximum thickness and minimum surface roughness (Ra) of the HVOF sprayed coating were defined at hardness of 1288.6306 HV, porosity of 0.0721 %vol., thickness of 322.0816 µm and Ra of 6.5551 µm, which can exhibited the optimum condition with oxygen flow rate of 280 L/min, propane flow rate of 19 L/min, powder feed rate of 107 g/min and spraying distance of 260 mm.