Tom Eddershaw reports from Trumpf's headquarters in Ditzingen, Germany, on how improved part design and new materials are the key to meet requirements in a changing automotive market
Automotive component design and the increasing reliance on producing cars with new lightweight materials – as well as some novel ways of using older materials – was one of the themes at this year’s Automotive Photonics conference, held by Trumpf on 27 January.
Hosted at the company’s headquarters in Ditzingen, Germany for the second time, an international audience of around 200 attendees heard customers and partners of Trumpf, as well as research groups, discuss how a changing automotive market is likely to benefit both users and manufacturers of laser systems.
Optimised car design and the design of automotive parts was outlined as an important way to reduce weight and therefore improve fuel efficiency, while, at the same time, making cars safer. Understanding the capabilities and opportunities provided by laser processing is key to the design process. Laser welding allows direct joining of parts without the need for flanges, for example, removing what can now be considered excess material and reducing mass.
Marc Kirchhoff, industry manager for E-mobility at Trumpf Laser- und Systemtechnik, explained that, by using laser processing, flangeless designs for a car’s B-pillar could be made, which can reduce the weight of the part by 0.5kg, a fall of around 40 per cent. He used the example of German electric vehicle company, Street Scooter, which uses flangeless design for the floor assembly of the car. The floor assembly component needs to be strong to carry both the weight of the car batteries and withstand crash impacts.
Kirchhoff also spoke about laser processing novel materials, in particular carbon fibre reinforced plastics (CFRPs). This lightweight material can now be cut at 20m/mm with a laser with only a small heat affected zone.
Professor Frank Henning at the Karlsruher Institut für Technologie continued on the theme and defined ‘lightweighting’ as a new part of the design process, saying: ‘It’s more than just design.’ He said that with new materials available – such as hybrids, composite materials, and material composites (which are very different) – it is not only the part that needs to be designed, but the composition of the part as well.
Combining different materials allows a part to take on multiple properties, as Stefan Heinz at Joma-Polytec pointed out; but, some materials have historically been difficult to combine. The method he discussed now allows the manufacturer to create a strong joint between a metal and a plastic by laser processing small troughs with overhangs into the metal. The plastic is placed on the join location and heated, causing the plastic to melt and fill the holes. Once the plastic sets, the metal and plastic are held together without the need for conventional joining materials, reducing weight and removing unnecessary fracture points caused by screw holes.
However, with all of the new materials being used, Klaus Löffler, director of international sales at Trumpf, spoke about the reappearance of aluminium in automotive manufacture. In the past, the metal had been used extensively in the automotive industry, then fallen out of fashion, and is now again being increasingly used – the new Ford F-150 is being produced using an aluminium body helping the pickup truck shed valuable weight and improve fuel efficiency.
But the reassessment of materials is not the only thing Löffler called for. The changing materials and market could be opening up opportunities to re-use and adapt old ideas. In his keynote speech he spoke about the importance of methods that may have not been viable years ago but could be more applicable now.
Electric vehicles were also a recurring theme at the automotive event as a solution to the energy concerns for inner city driving. Again, electric vehicles are reliant on lightweight parts to improve their driving range. Laser processing is expected to be used to reduce the cost of electric vehicles and this combined with better batteries and optimised performance, should increase the number of EV owners.
Keynote speaker Andreas Fuchs, general manager of public relations at Toyota Motor Europe, said that more cars are being bought and the automotive market is growing. It is now a case of optimising component design to make use of new materials and new manufacturing methods to reduce weight and improve safety, and the laser has a central role to play here.