Frankfurt, Monday, March 21, 2016 - Lightweight construction is essential for a resource-saving, energy-efficient environment. Just like aviation, the automotive construction sector is increasingly using lightweight construction solutions to reduce CO2 emissions. By 2020, lightweight construction around the world is expected to total EUR 140 billion for the transport sector alone, with growth rates of seven to eight percent. With this in mind, VDMA has established the Working Group Hybrid Lightweight Technologies. Representatives from user and supplier industries use this platform to exchange information and ideas on opportunities, technologies and materials for lightweight construction. Over the next few months, VDMA will hear from some of the exponents of lightweight construction on a loosely scheduled basis.
An interview with Marc Kirchhoff, Industry Manager Automotive / Lightweight Design and Electromobility at Trumpf Laser- und Systemtechnik GmbH and member of the Board of the Working Group Hybrid Lightweight Technologies.
What is lightweight construction all about?
Kirchhoff: Lightweight construction today, much more than in the past, is about lightweight designs. It is about flange reduction and new joining techniques. But it is also increasingly about hybrid lightweight construction, i.e. combining materials in useful ways. In vehicle construction, for example, this means that cars today are built from a mixture of materials – steel, aluminum, plastics and even carbon reinforced plastics.
To what extent does the topic affect a manufacturer of laser beam sources like Trumpf?
Kirchhoff: When it comes to the hybrid connections, the question is how to process these materials. Lasers provide a lot of options for doing this – cutting, structuring and more. The main issue is how all the different materials can be connected. Lasers are one of the tools with which mixed connections, such as those made from metal and plastic, can be produced.
Why is lightweight construction today usually associated with the car industry? It has long been an issue in the aviation industry.
Kirchhoff: Automotive construction is the driver of lightweight construction when it comes to production technology. After all, the focus of this sector is always on very large batches and very high quality requirements. Processing times here are much more important than in the aviation industry, for example. Automotive construction now demands much shorter cycle times for these components – the rise of fiber-reinforced plastics is clear evidence of this. The car industry is the source of many developments.
To what extent is lightweight construction driven by political provisions?
Kirchhoff: If the political constraints no longer accelerated consumption norms, this would almost certainly lead to a reduction in the pace of change – maybe not in lightweight construction, but certainly in drive technologies. Lightweight construction was already an issue before the EU's CO2 guidelines were defined. Consumption is undoubtedly one issue, but topics such as driving dynamics and enjoyment are also important. That motivates automotive companies regardless of the specified values.
How do lightweight construction and safety interact in car production?
Kirchhoff: Needless to say, everyone is trying to make vehicles safer and safer, despite the reduction in weight. The designers' main aim is to design every component in the best possible way. The B-pillar is an excellent example of this: developments are currently under way that will allow materials to be selected in line with the loads along the B-pillar. Combinations of steel, high-strength steels and plastics will be used here. Such a B-pillar offers the highest possible level of safety and is also much lighter than a purely steel construction.
Hybrid lightweight construction is the trend throughout the automotive industry. Are the days of steel and aluminum numbered?
Kirchhoff: There is definitely competition among the materials and material connections, but I don't think that one will entirely replace the other. When the first Audi was built completely from aluminum, many people thought that steel was a thing of the past. But the steel industry has put a lot of energy into development. One result of this was so-called tailored blanks – custom-made sheets in different shapes, thicknesses and strengths, which are now used as standard in cars. The development of high-strength steels is also a consequence of the competition between materials. We are seeing the same thing now, as plastics and hybrid components enter the running. Steel manufacturers will now try to develop even stronger steels, and the aluminum manufacturers are doing the same. The competition between the various materials is pushing everyone to achieve more. No technology has yet fallen behind.
Outside the automotive industry, where else is lightweight construction on the rise?
Kirchhoff: Automotive construction is undoubtedly one of the largest sectors in Germany, especially if we include the entire supplier industry. But lightweight construction is increasingly becoming an issue in other sectors, too – in mechanical engineering, for example. One of the key aspects is creating a more lightweight design for moving machine parts, in order to reduce energy consumption and allow components and axles to move more quickly. Every gram saved can be converted into speed gained. Lightweight construction has always been especially important in shipbuilding and aircraft construction.
You are on the Board of the Working Group Hybrid Lightweight Technologies. What do you consider the core advantage of this group?
Kirchhoff: Exchanging expertise. For example, we in automotive construction might come across a challenge and not realize until much later that the aviation engineers have already solved it. One industry might say that overmolding components is already standard, but for another it is totally new. This new platform means that everyone can complement one another's expertise, so that all the technologies and applications are driven forward.
So everyone talks to everyone else?
Kirchhoff: We have a good structure. We have defined the topic fields that attract the most interest from everyone involved. Joining technology is one example. The processes are now standard in steel construction, but far from it in hybrid lightweight construction. Our goal here is to standardize processes, and to say that a certain method allows us to achieve joining processes in hybrid lightweight construction under certain conditions. This would enable us to give designers and developers specific guidelines that tell them, for example, that yes, you can cover fiber-reinforced plastics with an aluminum skin, with the following technology and the following properties. That is the pinnacle of exchanging expertise.
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