Palestine Technical University Research Journal


The aluminum alloys of the 7xxx series consist of Al with Zn mainly, Mg and Cu. 7xxx aluminum alloys has high mechanical propertiesmaking it distinct from other aluminum alloys. In this paper, we examine the effect of adding Nickel and heat treatments on the microstructure and hardnessof the 7075 aluminum alloy. Were we added different percentages of nickel [0.1, 0.5, 1] wt% to 7075Aluminum alloy, and applied various heat treatments (artificial aging T6 and Retrogression and re-aging RRA) on the 7075 alloys that Containing nickel. By applying RRA treatment, we obtained better results than the results obtained by applying T6 treatment, and we obtained the high values ofhardness and a smoother microstructure for the studied alloys bythe addition of (0.5 wt%) nickel to alloy 7075.