Applications of age hardenable high strength aluminium alloys within the 6xxx series have many advantages compared with other groups of alloys in automotive fatigue loaded parts. Especially if the processing chain of manufacturing components can be more cost effective. Sheets and extrusions from alloys within 6xxx series are candidates when combination of strength and ductility is an issue. Hot forming has advantages compared with cold forming when dealing with spring-back, formability and microstructural control.

The innovation is to integrate forming technology with hardening heat treatment processing steps suitable for fully automatic production. The process involves a first sequence of solid solution heat treatment directly followed by sufficient cooling to supress precipitation of hardening particles in combination with deformation, i.e. the shaping process. Technically, the hot blank is moved to a position in a cooled die system and is pressed to a shape within a timeframe keeping full potential of hardening to expected mechanical strength for the given alloy.

An experimental set-up has demonstrated full hardenability of formed shapes, even for relatively thick sheets and extrusions of 5 mm. The material tested have been pressed from sheets and extrusions and demonstrate high mechanical strength in combination with reasonable ductility. The deformation itself also contribute to the final properties where a combined mechanism of dislocation substructure and precipitation seems to be the explanation.

Qualities within AA6082 and AA6010 have been tested with promising results for both extrusions and sheets. The mechanical properties of the alloys tempered to the maximum strength condition all show an improved strength – ductility combination compared to alternative processing with a potential of 350MPa in yield strength. The performance of this process is higher compared to traditional cold metal forming due to short process time, low-cost machinery and giving a high level of structural integrity of fabricated parts. The process is especially suitable for wheel suspension arms since a higher sheet thickness is required for these parts.