Formation of the structure of thin-sheet rolled product from a high-strength sparingly alloyed aluminum alloy “nikalin”

The regime of thermomechanical treatment of flat ingots of a high-strength sparingly alloyed alloy based on the Al–Zn–Mg–Ni–Fe system upon the production of thin-sheet rolled products with a reduction of more than 97% has been substantiated. Using experimental and calculated methods, the structure and phase composition of the experimental alloy in the as cast and deformed state and after heat treatment including quenching with subsequent aging have been studied. It has been found that the structure of the wrought semi-finished products after aging according to Т and Т1 regimes consists of the precipitation-hardened aluminum matrix and uniformly distributed isolated particles of Al9FeNi with a size of 1–2 μm, which provides a combination of high strength and satisfactory plasticity at the level of standard high-strength aluminum alloys of the Аl–Zn–Mg–Cu system. The fractographic analysis confirmed that the tested samples underwent a ductile fracture.