Open AccessInfluence of severe plastic deformation on the structure and mechanical properties of eutectic Al-Zn-Mg-Fe-Ni alloy
Author(s) -
И. Г. Бродова,
А. Н. Петрова,
Т. К. Akopyan
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/672/1/012022
Subject(s) - materials science , eutectic system , alloy , ultimate tensile strength , ingot , metallurgy , annealing (glass) , severe plastic deformation , indentation hardness , grain size , microstructure
The structure and phase evolution of the new eutectic high strength aluminium alloy Nikalin were investigated under high pressure torsion (HPT) by several numbers of the revolution of the anvil. The chemical composition of the investigated Nikalin alloy was as follows: Al (base)– 7.22Zn–2.95 Mg–0.52 Fe–0.57 Ni–0.2 Zr. (wt.%). The initial material was a coarse grained cast ingot after homogenization. It was established that the HPT process resulted in the deformation dissolution of the nanosized T-phase precipitates and the formation of a supersaturated aluminum solid solution simultaneously with the strong refinement of the structure to the grain-subgrain size of 130-150 nm. Due to that, the yield stress of the HPT alloy increased by a factor of 1.5, the ultimate tensile strength increased by a factor of 1.4, while preserving good ductility of 6-7%. The observed effect of the additional supersaturated solution upon HPT relative to the homogenized state appeared upon post-deformation annealing at 140 °C. An increase in the microhardness of the HPT alloy due to the MgZn 2 phase precipitation was observed at 0.5- hours of annealing.