Optimization of the Deposition Parameters of Stellite 6 Flame Spray Coating on 6153-T6 Aluminum Substrate

Aluminum alloys have high corrosion resistance and good mechanical strength-to-weight ratio and a relative low cost to meet the needs of the aeronautics, automotive, and defense industries, however, the wear resistance has some limitations. In this way, surface engineering has adopted methods to improve the wear resistance of aluminum alloys. Thermal spraying is a modern and versatile method, allowing rapid application of coatings on the substrate. Cobalt alloy reduces wear on the base metal surface due to the excellent performance of this coating. In this work, the goal is evaluate the influence of powder flame spraying process parameters, as standoff distance, preheating, oxygen and acetylene flow, carrier gas flow, powder feed rate and oxygen pressure in the alloy deposited on aluminum Al 6351-T6. To study the influence of the parameters the Taguchi design of experiment, with orthogonal matrix L8 was used. Coating adhesion to the substrate, sliding wear resistance, porosity and oxide content were evaluated. Experimentally, the results show efficacy in the reduction of wear, increase in adhesion and also reduction in the porosity of the coating.