Bookmark 11-29-2016

Precise Laser Drilling of CFRP Components

Developing a Systems and Process Technique to Meet Aviation Requirements

Thanks to their high potential for lightweight construction, composite plastics such as carbon fiber-reinforced plastics (CFRP) can be found in a vast range of aviation applications. These materials have outstanding properties, e.g. low weight and high stability at the same time. However, processing them is very demanding and expensive. Using mechanical techniques involves severe abrasion of tools, leading to significant quality problems.

In a new joint research project, four enterprises and the Laser Zentrum Hannover e.V. (LZH), Hanover, Germany, aim at further developing the laser drilling of composites for series production in the aircraft industry. The project’s focus is on designing an efficient systems and process technique that meets the demands of aviation.

Laser bores in an aircraft component of CFRP (© LZH)

The "Labokomp" Project

The name of the project is „Laserstrahlbohren von Kompositwerkstoffen für Luftfahrtanwendungen (Labokomp)" (Laser Beam Drilling of Composites for Applications in Aviation). The partners to the project are focused on the development of customized processing strategies using a new, high pulse laser beam source. This project is funded by the German Federal Ministry of Education and Research (BMBF) within the framework of the „KMU-innovativ: Photonik“ initiative for a duration of three years.

For aviation applications, in particular, the market potential of CFRPs is extraordinarily high. With the number of aircrafts produced rising at present, along with the high number of bores for riveted and screwed joints, there is a high demand for reliable, fast and affordable techniques to enable processors to stand up against international competitors. Laser beam drilling is an interesting alternative here.

To make sure the process is suitable for industrial application, users should have at hand tailor-made system, handling and monitoring equipment. This is the only way to provide for highly precise and dynamic handling and to enable processing of high-quality serial components.

Major Contribution by Enterprises and LZH

In the project, the small and medium-sized companies Invent GmbH and KMS Technology Center GmbH as well as the large companies Trumpf Laser GmbH and Premium Aerotec GmbH develop automatic clamping and positioning systems that include features such as detection and damping of vibration. Other than with conventional cutting methods, a single clamping unit serves for all component variants. Moreover, the supply and exhaust of process gases and emissions as well as the cooling of workpieces are optimized, thus accounting for a holistic approach to the overall process.

The LZH experts within the composites group of the production and systems department are mainly focused on investigations and material tests aimed at minimizing thermal stress on laser-drilled CFRP components, while, at the same time, increasing efficiencies by using tailor-made process control. In addition to the manufacturing of small components in large quantities, the investigations are aimed at making the novel process strategy available for the assembly of large structures, too, in the future.