Thermal stability of microstructure and properties of ingots and fine wires from Al–Zr alloys

The process of precipitation of Al3Zr particles in cast Al–(0.25–0.4) wt % Zr alloys manufactured by the induction casting method is studied. The effect of zirconium concentration on the microstructural parameters, hardness, and specific electrical resistance (SER) of cast alloys is investigated. The dependences of hardness and SER on the time of cast alloys annealing at 500°C are plotted. The parameters of the Johnson–Mehl–Avrami–Kolmogorov equation for alloys with different Zr content are determined. The optimal regimes of cast ingot aging are found. Fine wires with ∅ 0.3 mm are manufactured by the drawing method; their strength, SER, and hardness are studied in the initial state and after heat treatment. The tests of thermal stability of wires are carried out according to the state standard GOST R MEK 62004–2014.