Tribological behavior of NiAl-based intermetallic compounds in artificial seawater

The solid-lubricating material is a promising candidate for the tribo-pairs exposed in a seawater environment. In this paper, the tribological properties of NiAl-based intermetallic compounds in the seawater were investigated. The results revealed that NiAl-Cr(Mo)-Ag alloy exhibits the lowest friction coefficient (similar to 0.1) and wear rate (similar to 10(-7) mm(3)/Nm) compared to NiAl and NiAl-Cr(Mo) alloys, which is attributed to the solid-lubricating action of Ag. NiAl-Cr(Mo) alloy displays the highest friction coefficient, resulting from the severe abrasive action of the tribo-pair. The wear features of NiAl and NiAl-Cr(Mo) alloys are delamination and plowing effect, respectively. However, the worn surface of NiAl-Cr(Mo)-Ag alloy is almost smooth. Abrasive wear is dominated by the wear mechanisms of NiAl-based intermetallic compounds, while corrosion wear is mild.