Fabrication and study on tribological characteristics of bronze–alumina–silver composite under sea water condition

The bronze–alumina–silver composites were prepared by powder metallurgy technique (P/M). The tribological properties of composites sliding against AISI321 stainless steel pin were studied by using a pin-on-disk test machine under sea water condition. The silver showed the good lubricating effect in sea water. The addition of alumina improved the hardness and wear resistance of composites. The friction coefficient of bronze–alumina–silver composites increased with the increase of Al2O3. However, the specific wear rate of composites decreased with increasing Al2O3. Bronze–2 wt% Al2O3–7 wt% Ag showed the best tribological properties under sea water condition, especially, at the high loads and sliding speeds. The composites showed different wear mechanisms during the sliding process. Sea water showed the lubricating effect due to the presence of corrosion products on the worn surfaces.

► The silver is an effective solid lubricant in sea water environment.
► The Al2O3 shows an obvious dispersion strengthened effect on the bronze matrix.
► Bronze–7 wt% Ag–2 wt% Al2O3 shows the best tribological properties.
► Sea water shows the lubricating effect and corrosive effect.