Influence of oil-water mixing conditions on the friction and wear performance of ship tail-bearing materials

Abstract This study addresses the lubrication challenges posed by oil-water mixtures that arise when vessels encounter adverse maritime conditions, including collisions, grounding, and reefing, which can lead to failures in lubrication systems during navigation. The research focuses on three representative ship tail-bearing composites: polymer material(K4), thordon material(SR), and tenmat material(FR). Various volume fractions of oil-water mixtures were prepared, and the rheological properties of these mixtures were examined using a rotational rheometer (MCR102). Additionally, the variation of friction coefficients of the composites about load and linear velocity under different oil-water mixtures was analyzed using a Ring-Block Friction and Wear Testing Machine. Following the experiments, the surface morphology of the composites was assessed, and the wear mechanisms were analyzed using a laser interferometric surface profiler (LI-type), a confocal laser microscope (CLSM), and a scanning electron microscope (SEM). The findings indicate that, under all lubrication conditions, the friction coefficients of the three materials exhibit a gradual decrease with increasing load and linear velocity.Furthermore, the wear of the materials initially increases and then decreases with rising oil content, with higher oil concentrations in the oil-water mixture correlating with reduced wear. The study reveals that the three materials experience significant abrasive and adhesive wear under adverse oil-water mixing conditions. This research offers valuable insights for developing friction substitutes for oil-water mixing bearings in specialized operational environments and guides the design of friction components in such bearings.