Influence of Operating Parameters on the Reciprocating Sliding Wear of Direct Metal Deposition (DMD) Components Using Taguchi Method

Direct metal deposition (DMD) is an advanced additive manufacturing technology used to repair and rebuild worn or damaged components, to manufacture new components, and to apply wear and corrosion resistant coatings. DMD produces fully dense, functional metal parts directly from CAD data by depositing metal powders pixel-by-pixel using laser melting and multiple material delivery capability, DMD can coat, build rebuild parts having very complex geometries. The present work is aimed at determining the influence of operating parameters on the friction and wear of DMD components. The substrate chosen was mild steel and the deposited material was H13 tool steel. A design of experiments technique was adopted in the form of Taguchi's L9 orthogonal array. The selected parameters were coating thickness, applied load and temperature. Wear testing was done on the components using ball on flat reciprocating wear testing machine. The results were then analyzed and the major contributing factor towards wear was found out based on the ANOVA calculations. The general trend indicates that as the load increases the coefficient of friction decreases. Microstructure analysis using scanning electron microscope revealed adhesive wear and mild oxidation along the wear track. Porosity was also observed at various locations scattered along the wear track. (C) 2017 The Authors. Published by Elsevier Ltd.