Effect of seawater salinity on the fretting corrosion behavior of nickel-aluminum bronze (NAB) alloy

In industrial applications, components made by Nickel-aluminum bronze (NAB) alloys are commonly encountered by fretting corrosion. This study aims to investigate the effect of seawater salinity on fretting corrosion behavior of the material. Research indicates that due to the synergistic effect of wear and corrosion, both the friction force and wear volume reach the peak value under the salinity of 3.5%. The reduction in wear observed when the salinity increases from 3.5% to 7.5% can be attributed to the hydrolysis of water-soluble CuCl2 to produce Cu2O, which reduces the corrosion degree and provides a lubrication effect. Furthermore, the combination of chloride ions and aluminum leads to the formation of an AlCl3 passivation layer, which serves to protect the alloy surface.