ВЛИЯНИЕ ОТЖИГА НА ЭЛЕКТРОСОПРОТИВЛЕНИЕ И ТВЕРДОСТЬ ГОРЯЧЕКАТАНЫХ ЛИСТОВ АЛЮМИНИЕВЫХ СПЛАВОВ, СОДЕРЖАЩИХ ДО 0,5 % Zr

The study covers the influence of multi-stage annealing (up to 650 °C) on the value of electrical resistivity and hardness of low-alloy hot-rolled sheets made of aluminum alloys containing up to 0,5 wt.% of Zr. Experimental samples were produced in conditions close to those implemented in industrial machines for continuous casting and rolling. Testing methods including heat treatment were described. The structure of the cast (initial structure) as well as the structure of deformed experimental samples was analyzed. The graphs of the specific electrical resistivity (ρ) and hardness dependence on the temperature of the last annealing stage were drawn according to the results of the physical and mechanical tests. It was determined by computational and experimental techniques that the ρ value depends mainly on zirconium content in aluminum solid solution. The optimal ratio between zirconium content in alloy and annealing temperature providing the best combination of hardness and electrical resistivity was defined.