Sammendrag
The work-hardening of the solution-strengthened aluminium alloy AA5182-O is studied as a function of strain rate at room temperature. The main aim is to characterize the influence of strain rate and dynamic strain ageing on the work-hardening of the material. Tensile tests with constant nominal strain rates in the range from 10–6to 1 s–1were carried out; additionally, strain-rate jump tests were performed. The material exhibits a sharp yield point, a Lüders plateau, and serrated yielding within the actual range of strain rates. This indicates that the steady-state strain rate sensitivity is negative as a result of dynamic strain ageing. The serrations in the stress –strain curves and the workhardening are markedly reduced with increasing strain rates. In most cases, the jump tests exhibit the standard behaviour, i. e., after a transient period following the jump in strain rate, the stress –strain curve converges to the steadystate stress – strain curve at the new strain rate.