Experimental investigation of the influence of tribological parameters on the fretting wear behaviour of tungsten carbide WC-Co: Effects of load, duration, and frequency.

Key words:  fretting wear, tungsten carbide, materials tribology, vibration-induced wear, tribological parameters, wear mechanisms, WC-Co, mechanical contact

Abstract:

A comprehensive experimental investigation was designed to explore the fretting wear behaviour of tungsten carbide WC-Co (25% cobalt), a cermet known for its exceptional wear and deformation resistance in harsh industrial settings. The study systematically examined the effects of three primary parameters—normal load (ranging from 1 to 4 N), contact duration (2 to 120 min), and vibration frequency (10.75 to 19.66 Hz)—using a custom-built ball-on-flat test rig operating under dry conditions. A multifactorial analysis of variance (ANOVA) was employed to assess the individual influence of each parameter on material mass loss. Findings reveal that both load and contact duration have a highly significant impact, whereas frequency shows a moderate but statistically meaningful effect. A nonlinear interaction between the parameters and the wear response was observed, characterised by an initial running-in phase transitioning into a steady-state wear regime. Microscopic analysis of the wear scars uncovered two distinct zones: a central, nearly circular adhesion zone and a peripheral elliptical sliding area. These morphological patterns were found to correlate closely with the measured mass loss. The results show that both load and contact duration have significant effects on mass loss (ANOVA, p < 0.001), and the developed regression models explain over 96% of the variance, providing quantitative prediction tools for wear.