LASERS AND LARGE STRUCTURES

Fraunhofer IAPT operates its own competence center for laser processing and the creation of large structures. The specialized know-how encompasses both laser-based joining technologies and a variety of additive manufacturing processes for metals, plastics, and concrete. Development goals and tasks focus on innovative and optimized processes, improved material properties, required processing and monitoring systems, and associated automation solutions.

 

High-power laser applications

The Fraunhofer IAPT center for lasers and large structures provides its cooperation partners with unique system technology for these tasks. A 30 kW fiber laser is available for welding thick sheet metal with a welding penetration depth of up to 25 mm in a single position. Cutting and material removal processes for a variety of materials are examples of further high-power laser applications. Moreover, numerous robot systems and a portal system for processing components up to 30 meters in length can be utilized.

 

Laser and laser hybrid welding

As the successor to LZN, Fraunhofer IAPT has gained years of experience in laser and laser hybrid welding. In major publicly funded shipbuilding projects, low-distortion joining processes have been developed since 2009 that, through a combination of laser beam and electric arc, enable the achievement of higher welding speeds and reduce heat input, thus contributing to a reduction in component distortion due to thermal influences. The gap-bridging capability has also been significantly improved (cf. p. 64: Report on ShipLight). In addition to shipbuilding applications, Fraunhofer IAPT has also been immensely successful in the development of highly productive laser welding processes for the automotive industry and both crane and rail vehicle manufacturing.

 

Large sturctures

Large structures are not only welded at Fraunhofer IAPT, but also increasingly built through additive manufacturing. Additive manufacturing offers a maximum degree of design freedom and a function integration option, even for large-scale compo-nents. The particular challenge here is to achieve a high build rate while, simultaneously, ensuring no loss in accuracy. On the one hand, this enables the rapid and efficient creation of large structures while, on the other, keeping the level of post-processing low. Component dimensions mean that robot-assisted use of the DED process (directed energy deposition) is predestined for metals and the FDM process (fused deposition modeling) for plastics. 3D printing of concrete is also part of the research conducted at Fraunhofer IAPT. Additive manufac-turing with concrete makes a high degree of automation and realization of additional functions such as air conditioning in technical buildings possible.