The variation of tensile characteristics of Al–2 wt.%Ag and Al–2 wt.%Ag–1 wt.%Sn alloys during transformation

Effect of tin addition and heat treatment on the work hardening characteristics of Al–2 wt.%Ag alloy during phase transformation has been studied in the deformation temperature range from 503 K to 583 K. The fracture strain ɛf, and dislocation slip distance L increased with increasing deformation temperature. On the other hand the coefficient of work hardening χ = δσ2/δɛ, the fracture time tf, yield stress, σy fracture stress, σf decreased with increasing deformation temperature and exhibited an abrupt increase at about 553 K. The Sn-free samples were generally harder than the ternary alloy. The activation energy of the fracture mechanism in both alloys was around 26.8 ± 3 kJ/mol and 34.6 ± 3 kJ/mol before and after transformation temperature (553 K), respectively. The quenched samples are harder than those of slowly cooled samples. From X-ray analyses it is clear that when lattice strain ɛ and dislocation density ρ increases, the crystallite size η decreases.