Due to the outstanding ratio of mechanical strength to weight, carbon fiber reinforced plastics (CFRP) are an important material for lightweight construction applications in the automotive and aerospace industries. As a result of the inhomogeneous mechanical and thermal properties of carbon fibers and matrix material, the processing is comparatively difficult. The difficulties are the delamination of the fibers from the matrix, the thermal load on the matrix and a high tool wear by the very hard carbon fibers. For this reason, laser radiation as a non-contact and wear-free tool, offers a great potential to make the CFK processing more efficient. To keep the thermal influence on the work piece as small as possible, especially the use of ultrashort pulsed laser radiation for CFRP processing is being evaluated.
ResultsCopyright: Lehrstuhl für Lasertechnik LLT
Using ultrashort pulsed laser radiation and an average power of about 30 W, the processing of CFRP is realized with heat affected zones under 5 µm at removal rates of 30 mm³ / min. When using an average output power of 400 W, removal rates of 380 mm³ / min can be achieved with a heat-affected zone of approximately 45 µm. The ablation process can be utilized to realize separating cuts as well as 2.5 dimensional surface geometries as a preparation for repair operations.