Correlation between microstructure and erosion-corrosion behavior of a nickel-aluminum bronze produced by continuous casting and powder metallurgy

In this study, Powder Metallurgy (PM) was used to produce Nickel–Aluminum Bronze (NAB) alloys for naval application. The effect of an annealing treatment on the microstructure, corrosion and erosion-corrosion resistance was investigated. In comparison to a commercial continuous cast NAB alloy, the α phase grains present in the microstructure of the PM alloy are coarser and more equiaxial. In contrast, the PM material exhibits finer κ precipitates. The smaller size of the κ phases in the PM samples results in a more homogeneous corrosion. Furthermore, the larger α grains assist in enhancing the erosion-corrosion resistance of the PM material.