Making lightweight construction suitable for series production
04/24/2017

Figure 1: On the way to series production: 3D CFRP processing. (Photo: LZH)

Figure 2: Automatically scarfed CFRP surface. (Photo: LZH)

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has developed processes for cutting three-dimensional components, using an actual component from the automotive branch. The process uses a newly developed high-power disc laser from the Trumpf Laser GmbH, with a pulse duration of tp = 30 ns and a maximum average output power of PL = 1500 W. The KMS Automation GmbH has developed clamping devices which are adapted to the special features of laser material processing.  An exhaust system to capture the process emissions is directly integrated in the clamping unit. The companies Volkswagen AG and INVENT GmbH have investigated the influence of laser processing on the characteristics of the component as well as on the subsequent processes.

Repairs: Scarfing curved surfaces
„Repairing three-dimensional CFRP components is presently very time-consuming and costly,” explains Sven Blümel, project manager from the Composites Group at the LZH. “We can now scarf components with curved surfaces with short process times, as a preparation for repair. Subsequently, the scarfed areas are closed with a so-called patch, an accurately fitting replacement part. This is an important step in increasing the lifetime of CFRP body parts.” This concept for the following repair steps was developed by the Institute of Polymer Materials and Plastics Engineering (PuK) of the Clausthal University of Technology.

Directly capturing process emissions
Emissions from standard processes must be known and controllable, in order to ensure a safe workplace. This is why the Safety Technology Group of the LZH has investigated the emissions from the cutting and scarfing processes. Based on the composition of the process emissions, the Jenoptik Automatisierungstechnik GmbH has developed a completely regenerative, continuously working, exhaust cleaning system that does not need additional filter material.

Applications have been the focus of the project HolQueSt. The Volkswagen AG has accompanied the complete development process. “The successful completion of the project has brought us a step closer to series production”, concluded Sven Blümel.

About HolQueSt 3D
The project „3D high-power laser processing for increasing the quality and efficiency for the reliable, automated manufacturing of CFRP lightweight construction structures” (HolQueSt 3D) was subsidized with approximately 4 million euros by the Federal Ministry of Education and Research (BMBF) within the funding initiative “Photonic Processes and Tools for Ressource-Efficient Lightweight Construction”. The project partners are Volkswagen AG, Jenoptik Automatisierungstechnik GmbH, Trumpf Laser GmbH, Invent GmbH, KMS Automation GmbH, the Clausthal University of Technology and the Laser Zentrum Hannover e.V.

There are two figures for this press release.

 

Laser Zentrum Hannover e.V. (LZH)

As an independent, non-profit research institute, the Laser Zentrum Hannover e.V. (LZH) stands for innovative research, development and consulting. The LZH is supported by the Lower Saxony Ministry for Economics, Labour and Transport and is dedicated to the selfless promotion of applied research in the field of photonics and laser technology. Founded in 1986, over 170 employees are now working for the LZH.

The focus of the LZH lies on the fields of optical components and systems, optical production technologies, and biomedical photonics. Interdisciplinary cooperation between natural scientists and mechanical engineers makes innovative approaches to challenges from the most different areas possible: from the development of components for specific laser systems to process developments for the most diverse laser applications, for example for medical technology or lightweight construction in the automotive sector. Seventeen spin off companies have emerged from the LZH up to now. Thus, the LZH has created a strong transfer between fundamental science, application oriented research, and industry.