What are the coming trends in lightweight automotive construction?

voestalpine is a leading supplier to the automotive industry thanks to its lightweight steel solutions. But how significant will lightweight automotive construction actually be in the future? Below, voestalpine’s researchers and developers take a look at the trends in lightweight construction as they relate to electromobility. One thing is certain, however: Flexibility is a must!

Lighter vehicles need less energy than heavy ones to gather speed. This principle also applies to electromobility. Hence lightweight automotive construction will play a significant role in vehicles of the future as well.

Trends in lightweight construction

voestalpine Automotive Components Schwäbisch Gmünd, Germany, is one of the Group’s centers of excellence for automotive components. “All automotive segments feel the pressure to work toward economical lightweight construction, albeit to different degrees,” is how Florian Gerstner (Department Head, Tec Center, Prototype Construction, and Small Series Production) describes the current situation, “but the pressure will play an even greater role in the future, absolutely. We’ve been analyzing this trend for a number of years—and we’re prepared.”

Judging from the discussions around developments in electromobility, lightweight construction will be in demand especially for electric vehicles (EVs) in urban centers. The German trade publication, Automobil-Industrie, has done the math: The drive efficiency of a vehicle that weighs 100 kilograms less improves by just under 5.5% during acceleration processes that occur with particular frequency in urban traffic; this is why energy savings of more than 4% may be expected in real-world operations.

Mixing is the thing to do

voestalpine’s specialists are also fully prepared for the trend toward materials mixtures in automotive engineering, Marcus Wiemann (Project Manager, Technology Development) emphasizes: “When it comes to mixed construction types involving steel and aluminum, for example, the expertise of our automotive components companies in Bunschoten and Schwäbisch Gmünd is nothing short of excellent. This includes sophisticated joining technology.” He adds that, in the future, too, materials mixes will be driven largely by customers and volume. According to him, there will be a growing trend toward light metal in the small yet very demanding premium segment; equally conceivable is the targeted use of carbon fiber-reinforced components. “The more economical construction method using high and highest tensile steels, in particular, will continue to dominate the small and medium-sized vehicle segment, even in the future; we developed a new lightweight construction solution using steel called phs-directform precisely for this purpose,” says Andreas Sommer (Team Manager, Hot Forming Development).

Individual concepts are indispensable

According to a study titled, “The Role of Steel in Electromobility”, which the Handelsblatt Research Institute (HRI) conducted at the behest of voestalpine, combinations of steel with synthetics to (partially) strengthen structural components will become highly significant in the future. The HRI study does not posit, however, that such combinations will be used across the board; instead, they will be a factor in individual concept solutions. There will be many more of those in the future, because the respective customer requirements in the continental European markets will become ever more differentiated and thus require flexible autobody platform concepts.

But it is already clear at this time that high demand for aluminum will lead to delivery bottlenecks. According to the HRI study, demand for aluminum will rise to up to ten million tons by 2030. Marcus Wiemann: “Intelligent solutions involving steel thus will be in greater demand than ever before.”

Intelligent roll forming for the future of e-mobility

Geometrically sophisticated sections that are manufactured by voestalpine Krems GmbH ensure stable, low weight—even in battery cases. Thanks to intelligent roll forming, crosspieces and contours create complex, high-tensile steel sections. “Assuming identical crash performance and neutral weight, multi-chamber sections also help to generate a cost advantage relative to extruded aluminum sections,” explains Matthias Stumvoll of the Roll Forming Product Development department of voestalpine’s Krems-based company.

Thanks to its expertise in both materials and processing as well as the know-how of its employees, voestalpine is fully prepared for e-mobility’s lightweight construction requirements of the future.