The portevin le chatelier effect in Al-alloys with Cu, Mg and Li
Abstract
Serrated yielding properties of aluminum alloys with copper, magnesium and lithium were investigated. 2024, 2014, 7075, AlCu4Ti and 2024 containing lithium additions aluminum alloys were used. Melting was carried out in an induction furnace under argon gas protection, the casting is done under vacuum. To obtain the maximum strength and hardness, the specimens were solution heat-treated fewer than 495°C and quenched in water at room temperature. They were then aged naturally and artificially. The specimens were aged naturally at room temperature in one week or artificially at 120°C in 24 hours. All the specimens were subjected to tension tests. The strain rates were 0.521, 1.042 and 5.208 respectively. For a strain rate of 1,042 10-3 s-1, serrated yielding was observed.