The effect of trace levels of Ni and V on the microstructure and properties of four common aluminum alloys

The effect of nickel and vanadium with concentrations from <100ppm to ~550ppm on microstructure, mechanical properties and corrosion behavior has been investigated for aluminium alloys 356, 6060/6063, 3004 and 5182. While the Ni and V additions appeared to have no adverse effect on strength, ductility was reduced by the presence of Ni but it was improved by the presence of V for all alloys. Low Ni combined with high V levels gave the best corrosion performance in all four alloy systems. However, there was no difference in corrosion between alloys with low (50ppm) Ni and low (150ppm) V and other combinations. It appears that Ni and V levels may be allowed to increase together within current alloy specifications without detrimental effects on properties. However, high Ni and low V concentrations may reduce ductility and corrosion performance. Some caution should be exercised in allowing Ni to increase alone