The tribocorrosion mechanism of NBR/Cu in the deep sea

Tribocorrosion behavior of materials under deep-sea conditions remains poorly understood, especially for polymer-metal composites. The tribocorrosion behavior and failure mechanism of Cu(Zinc-copper-tin alloy)-NBR(Nitrile Butadiene Rubber) under deep-sea hydrostatic pressures was investigated using in-situ triboelectrochemical testing combined with surface analysis techniques. Results indicates that after wear initiation, the open-circuit potential of NBR/Cu shifts negatively, and the self-corrosion current density increases. With prolonged friction, NBR transfers to the copper matrix, forming a protective transfer layer that mitigates Cu corrosion under water lubrication. The synergistic effect is predominantly driven by Cl − -induced enhancement of mechanical wear, with hydrostatic pressure amplifying this interaction. This study provides theoretical guidance for developing durable surface protection strategies in deep-sea engineering applications.