ABSTRACT
Aluminium is a relatively expensive metal because its extraction from the mineral, bauxite, is energy intensive. Aluminium has low density, high ductility, high thermal and electrical conductivity, good corrosion resistance, attractive appearance and it is nontoxic. The pure metal is deficient in two respects, mechanical strength and elastic modulus, and aluminium alloy development was driven by the need to improve them without sacrificing corrosion resistance. The chapter discusses the physical metallurgy of some standard alloys. Standard commercial alloys are based on the aluminium-copper-magnesium, aluminium-zinc-magnesium and aluminium-magnesium-silicon systems. The most common casting alloys are based on the eutectic aluminium-silicon system and are characterized by fluidity of the liquid metal and low contraction on solidification. The chapter also provides information on corrosion resistance of pure aluminium in aqueous media, aluminium alloys in aqueous media, and aluminium and its alloys in air.
