Uncertainty-based comparison of conventional and surface topography-based methods for wear volume evaluation in pin-on-disc tribological test

Precise wear evaluation is essential to develop prediction models, applied to design materials, components and to optimise new manufacturing processes. Pin-on-disc is a widespread standardised conventional sliding wear test. Conventional characterisation of resulting wear exploits gravimetric or profilometric techniques. These have inadequate precision and accuracy for applications characterised by low-wear and uneven morphology and are being replaced with high-resolution and information-rich inspections to measure surface topography. Metrological characterisation of topography-based methods still lacks in literature, which prevents the performance comparison with conventional techniques. This paper develops a framework to evaluate topography-based methods' measurement uncertainty and compare methods' performances accordingly on experimental wear data on PTFE and Aluminium. Results show that topographic methods improve pin-on-disc characterisation's reliability.