Assessment of the tribological and wear performance of new duplex AlTiN-based coating systems at high temperatures when threading super duplex stainless steel

Abstract

During machining, a significant amount of energy is transferred at the cutting interfaces (tool/chip and tool/workpiece) to perform a cut. Tribology is the science of how surfaces interact when cutting metal, describing the physics and mechanics characterized by high loads and temperatures at the cutting interface. This paper explains how to determine the energy consumption required to make a cut, considering different combinations of cutting tool/coated surface and the wear characteristics of each one. Moreover, this paper finds the correlation produced by the effect of the heavy-load high-temperature on the friction condition between the interactive surfaces. Based on these findings, cutting tests (threading operations) were conducted to verify the tool wear mechanisms of the different AlTiN-based coatings, the amount of energy each consumed to perform the cut, and their tribological behaviour. The cutting test confirmed the tribometer simulation result. The AlTiNOS + WC/C coating demonstrated the minimum coefficient of friction in both the experimental and simulation analyses, while the AlTiNOS + TiB2 coating possessed a better combination of wear resistance and mechanical properties.