Friction–wear behaviour of wood–plastic composites against WC–Co under low–temperature sliding conditions

This study investigated the friction and wear behaviour of wood–plastic composite (WPC) against WC–Co under dry and low–temperature conditions using 5 min pin–on–disc tests. The effects of normal load and rotational speed on the coefficient of friction (CoF), wear rate, and worn surface morphology were analysed. The results revealed that increasing normal load and rotational speed reduced the CoF but increased the wear rate. Compared with dry conditions, low–temperature conditions reduced the CoF by 4.2–10.7% and the wear rate by 23.2–57.3%. ANOVA identified normal load as the dominant factor affecting both responses. Test environment, normal load, rotational speed, and the load–speed interaction significantly affected the CoF, whereas only normal load and rotational speed significantly affected the wear rate. Low–temperature conditions restricted HDPE matrix softening and plastic flow and improved the stability of the wood flour–HDPE interface. This reduced material adhesion, wood flour pull–out, and interfacial damage, resulting in lower CoF and wear rate. These findings provide a clearer understanding of the tribological mechanisms of WPC under low–temperature sliding conditions.