Fraunhofer Institute for Laser Technology ILT in Aachen will showcase a broad variety of laser technologies for lightweight construction at the LASER World of Photonics trade fair in Munich, Germany from June 22 to 25, 2015.
Truck seat in lightweight design, which is up to 20 kg lighter than conventional seats, partly thanks to the seat base made of glass-fiber-reinforced plastic, developed at Fraunhofer ILT. © Fraunhofer ILT
Lasers can enable a large number of cutting and joining processes. With the development of novel technologies, it is possible to develop considerably lighter and highly stable metal parts that have hollow structures.
Lightweight construction materials, such as aluminium and light carbon composites, are commonly used - the former in constructing car bodies and the latter for aircraft fuselages. However, there are still many more prospective lightweight construction technologies that are capable of enabling faster manufacturing processes and rendering lighter and more rugged materials. Laser technologies play a key role here, and this will be demonstrated by several exhibitons by the Fraunhofer Institute for Laser Technology ILT during the LASER World of Photonics.
The most attractive exhibit is the a row of letters forming the word “light”, each letter measuring 2 m high. Each letter is fabricated from a complicated, porous mesh structure. Fraunhofer ILT works in tandem with industries for the development of similar weight-optimized metallic components. Bespoke tools and components can be manufactured commercially using 3D printing. The LIGHT exhibit is a stunning example of a lightweight stable structure.
The expertise of Fraunhofer researchers lies in the manufacture of metallic components that have the same kind of lightweight structure. They accomplish this using the selective laser melting (SLM) technique that has seen significant improvements in the past few years. This technology is comparable with 3D printing, and deploys a laser beam for melting powder with very high accuracy based on CAD data instructions.
The melt slowly hardens to form layers of a few micrometers thick, thus creating a component layer by layer. SLM techniques were also deployed by researchers for the development of a lightweight and highly stable control arm support for a sports car. The wheels are separately suspended from the control arm, which features a hollow structure rendering higher stability and lower mass in comparison to machined or cast components. Without SLM techniques, it is not possible to produce this kind of highly complex, hollow structure.
As it is important that weight savings do not compromise stability, it is a challenge to manufacture lighter components and vehicles. Hence, present-day lightweight construction is mostly a combination of different materials such as fiber-reinforced plastic (FRP) and aluminium, each selected for being suited for a particular purpose. Since FRP stability suffers when it is combined with other parts using screwing, combination of materials is performed by gluing them together.