Held at the Heritage Motor Centre, Gaydon, the Automotive Lightweighting & Manufacturing conference, held over two days in March, proved to be a successful event to encourage collaboration between automotive manufacturers and automotive suppliers alike.
A wide range of attendees represented premium OEMs, volume OEMs, Formula 1, FEA/CAE consultants, steel, aluminium and composite materials suppliers. There were also fasteners and bonding suppliers and manufacturing companies ranging from advanced sheet metal forming to composite infusion and from composite laminating to additive manufacturing and 3D printing.
During presentations from OEMs and suppliers, it became clear that different materials and technologies are often mixed and matched to achieve the desired design goals. For example, a body shell may have a steel ‘B-pillar’ for rollover protection/safety but with aluminium panels making up most of the floor and an aluminium ‘A-pillar’ where the shape-induced stiffness allows for the lower density material.
There was interesting information on Superformed aluminium panels, allowing very complex shapes to be created from sheet material using air pressure at high temperatures. Alternatives were the faster, but perhaps less-proven, processes of Magnetic Pulse Forming and Electro-Hydraulic Forming. These involve very high speed ‘impact’ forming of sheet material using either a magnetic field to pull the sheet over a die or an electric current discharge into water to create a shockwave to force the material over a die.
In terms of composite materials, the key discussion points were: cycle time, percentage waste, recyclability and component joining
Of greatest importance was cycle time since, in terms of body production, the ‘one minute’ composite parts are only just starting to become possible. An important point made during debate concerned whether cycle time was ‘cure time’ or the whole stage from raw materials to finished component.
There seems to be an Automotive industry mind-set to ignore the use of composites in the Aerospace industry. Certainly, production volumes are not the same, but the Aerospace industry has been using composites and 3D printed parts on aeroplanes for many years now. There certainly appears to be potential for crossover.
Additive manufacturing is very much in its infancy. It became clear during the conference that aluminium is only starting to catch up with the traditional steel production methods. The big news in lightweighting is definitely composites. There is extensive effort currently in this field but cycle times, material waste, recyclability and repair, to name a few, are technical challenges still be to solved before it can start to catch up to the metals for high volume production.
Graphite sees additive manufacturing following hot on the heels of composites and there is even an overlap with composites – both through hybrid manufacturing or producing composite parts in an additive fashion. With greater investment and R&D into materials and machines to create high-end engineering materials with low production times, this production method could see huge steps in producing optimised structures with minimal costs. Multi-material systems are starting to appear and this would give the benefits of high-end composite structures with the low waste required of the high volume automotive industry.