Tailoring microstructure of a nickel aluminium bronze by hot extrusion and its impact on mechanical and corrosion behaviour

The effect of hot extrusion on microstructural evolution, mechanical properties, corrosion, and erosion-corrosion behaviors of a nickel-aluminium bronze (NAB) alloy (Cu-9Al-4.5Ni-4Fe-1Mn, wt%) was investigated. After hot extrusion, the microstructure was refined and become more homogeneous. In addition, the layered structures were broken and sepheroidized. These microstructural changes lead to improved mechanical behavior (hardness, strength, and elongation) and higher resistance to corrosion/erosion-corrosion. The reduced potential between phases in hot-extruded NAB alloy, the denser and more uniform corrosion layer, and its strong bonding to the substrate, all lead to improved corrosion resistance, especially in flow conditions.