The effect of quench interruption and direct artificial ageing on the hardening mechanisms during hot deformation and die quenching in AA6082Wednesday (06.11.2019) 14:35 - 14:55 Part of:
The automotive industry is searching for lightweight solutions to meet emission regulations. Development of an integrated hot forming and in-die quenching process will leverage use of age-hardenable aluminium alloys with high specific strength for applications in volume car manufacturing. Quench interruption and direct artificial ageing may reduce the cycle time in a die-quenching process. However, this alters the temperature exposure of the part, and thereof, an altered precipitation and clustering sequence during hardening. To investigate the effect of modified precipitation and clustering, the process has been simulated by application of a water-cooled compression tool to control the combination of a temperature drop and simultaneous deformation prior to ageing. Extruded 4,6 mm thick AA6082 profiles are deformed during different quenching rates and directly transferred to subsequent artificial ageing from various temperatures between room temperature and 200°C. The results indicate no reduction in yield stress or elongation after direct ageing from 200°C compared to specimens cooled to room temperature before ageing.