Performance of underwater laser cladded nickel aluminum bronze by applying zinc protective layer and titanium additives

The requirement of repairing damaged surface of nickel aluminum bronze (NAB) parts from underwater environment is urgent in recent years. In this paper, a novel approach to underwater laser cladded NAB by adding Ti and applying Zn protective layer has been reported. The materials fabricated underwater from this approach possess desirable performance. Ti additives increases the surface tension in melting pool, and prevents the high-speed water jet from invading the melting pool. Therefore, pores are almost disappearing. Due to the fast heat loss during underwater laser cladding process, the microstructure of underwater laser cladded nickel aluminum with adding titanium is fine, homogeneous and stable, in addition, the heat affected zone is small. Electrochemical results shows that the corrosion resistance of underwater laser cladded nickel aluminum bronze with adding titanium is better than that of substrate. In this study, the underwater environment is favorable for manufacturing a good material by using laser processing technology. The results of this study will provide meaningful reference to repairing NAB parts in underwater environment.