The Effect of Heat Treatments and Nickel Additive on The Microstructure and Tensile Properties of 7075 Aluminum Alloy

Mohamad Yehea Al nefawy; Fouad El dahiye; Mahmoud Al Assaad

doi:10.33261/jaaru.2020.27.2.014

Mohamad Yehea Al nefawy Mechanical and Electrical Engineering Collage, Al-Baath University, Homs, Syria
Fouad El dahiye Mechanical and Electrical Engineering Collage, Al-Baath University, Homs, Ssyria
Mahmoud Al Assaad Mechanical and Electrical Engineering Collage, Al-Baath University, Homs, Syria

DOI: https://doi.org/10.33261/jaaru.2020.27.2.014

Keywords: Al-Zn-Mg-Cu Alloys, Retrogression and re-aging RRA, Artificial Aging T6, Nickel additive, Tensile Properties, Microstructure.

Abstract

The aluminum alloys of the 7xxx series consist of Al with Zn mainly, Mg and Cu. 7xxx aluminum alloys has high mechanical properties making it distinct from other aluminum alloys. The effect of adding Nickel and heat treatments on the microstructure, formed phases and tensile properties of the 7075 aluminum alloy were studied in this paper. Different percentages of nickel [0.1, 0.5, 1] wt% was added to 7075 Aluminum alloy, and various heat treatments (artificial aging T6 and Retrogression and re-aging RRA) was applied on the 7075 alloys that containing nickel. The results obtained by applying of RRA treatment were better than the results of T6 treatment, the tensile properties increased and the microstructure became softer by adding nickel to the studied alloys. The maximum tensile strength of 7075 aluminum alloy was (UTS = 437 Mpa) when RRA heat treatment was applied and 0.5% nickel was added.