Enhanced tribological performance of functionalised surfaces using Machine Hammer PeeningWednesday (28.09.2016) 10:00 - 10:15 Part of:
Machine Hammer Peening is a surface treatment technique originally developed for smoothening tools and mould surfaces. Treated surfaces are locally cold worked, which results in a hardness increase and the induction of compressive residual stresses. In the present work, the feasibility of using this technique as a tool for surface functionalisation is investigated. Tungsten carbide particles were embedded onto selected substrates using machine hammer peening. The particle embedment quality of the engineered surfaces was evaluated and correlated to the substrates’ mechanical properties. The resulting tribological performance was investigated under reciprocating sliding conditions and the dominant wear mechanisms were correlated with the diameter of the embedded particles. Besides a higher wear resistance, surface functionalisation using machine hammer peening allows the in-situ generation of low friction tribofilms during the rubbing process via a tribochemical reaction between embedded tungsten carbide particles and sulphur-containing lubricant additives. These results open the possibility to develop tailor made wear resistant surfaces for reacting with specific lubricant additives, enabling a holistic design of tribological systems.