Development of an Optimum Consumable Alloy for Low Heat Input Welding of Nickel Aluminum Bronzes

Nickel aluminum bronzes are used in ship and submarine sea water handling, propulsion and combat systems equipment, as well as in a range of commercial high performance components. Usually, when these alloys fail, they fail by a surface sensitive mechanism such as wear, corrosion, dealloying, cavitation-erosion or corrosion fatigue. To determine if these surface properties could be improved with laser cladding, a laser cladding method was developed and the processing-structure-property relationships were studied. Microstructures and properties were found to be highly dependent on heat input. To reduce this sensitivity to heat input and further improve properties, work to develop an optimum consumable alloy was undertaken. The effects of additions of chromium, zirconium, and titanium were investigated along with the effects of composition variation within the range allowed by various standards. Work so far reveals three possible alloying approaches. Using these alloying approaches, reductions in the sensitivity of microstructures to heat input and property improvements are possible.