Tribological properties of bronze–graphite composites under sea water condition

Bronze–graphite composites containing 8.4∼15 wt% of Ni-coated graphite were fabricated by P/M method. The tribological properties were investigated under sea water condition. The friction coefficient of composites decreased with increasing graphite content. The wear resistance was improved by the addition of Ni-coated graphite but degraded at high graphite content. The results indicated that bronze–nickel coated graphite composites showed much better tribological properties in comparison with bronze and bronze–uncoated graphite composites. The composite with 11.7 wt% nickel coated graphite showed the best tribological properties. The addition of nickel coated graphite not only increased the mechanical properties, but improved tribological properties.

► The graphite is an effective solid lubricant in sea water environment.
► The nickel coated graphite has a good strengthening effect on bronze.
► The critical concentration threshold of nickel coated graphite is 11.7 wt%.
► The corrosion of sea water increases the specific wear rate of specimens.
► The corrosion products show a lubricating effect.