The Influence of Microalloying on the Thermal Treatment of Aluminum Bronzes

Abstract

At present, with the development of electric vehicles, great attention is paid to alloys which have very good electrical conductivity, corrosion resistance and resist to high temperatures. These alloys include aluminum bronzes. The electrical conductivity is the higher the finer is the grain or the less it contains almost non-conductive oxides, non-metallic inclusions, porosity, etc. Aluminum bronzes are foundry alloys that exhibit good electrical properties, very good sliding properties at high mechanical values, are resistant to corrosion and heat, have high resistance to acids and alkalis, so they are successfully used to work in aggressive environments. Aluminum increases strength and hardness, approximately 10 wt. % Al dissolves in copper, the alloy structure consists only of crystals α (cubic surface centered grid). Higher Al content also produces fragile crystals γ2 (Cu9Al4) and the alloy is harder and more fragile. The properties of aluminum bronzes with the structure of crystals (α + γ2) have a considerable influence on the cooling rate. Foundry bronzes are also used for more loaded wreath of gears, screw wheels, pump seats, impellers and distributor wheels, heavy load bushings and plain bearings.