Tribological behavior of Cu-15Ni-8Sn/graphite under sea water, distilled water and dry-sliding conditionsCu-15Ni-8Sn/石墨复合材料在海水、去离子水和干摩擦中的摩擦学行为研究

The tribological behaviors of Cu-15Ni-8Sn/graphite composites with the graphite content of 38 vol.% against AISI321 stainless steel under dry-sliding, deionized water and sea water were investigated on a block-on-ring configuration. The results indicated that the friction coefficient was the lowest under dry-sliding, and the highest in deionized water. The wear rate decreased to reach the minimum value of 1.39×10-15 m3/(Nm) in sea water and in deionized water, it increased to the maximum value of 5.56×10-15 m3/(Nm). The deionized water hindered the formation of tribo-oxide layer and lubricating film, which resulted in the largest friction coefficient and wear rate. In sea water, however, the corrosion products comprised of oxides, hydroxides and chlorides were found on the worn surface, and the compacted layer composed of corrosion products and graphite played an important role in keeping the excellent wear resistance. It was elucidated that the tribological behaviors of Cu-15Ni-8Sn/graphite composite were powerful influenced by the friction environments.