H. Dittmar
P. Jäschke
O. Suttmann
S. Kaierle
L. Overmeyer

Online laser-based repair preparation of CFRP supported by short coherent interferometry

10th CRIP Conference on Photonic Technologies LANE 2018
Type: Zeitschriftenaufsatz (reviewed)
Repair of CFRP parts still requires manual labour to a vast extent. Laser technology offers a solution to automate the preparation of a part’s damage zone by ablation. It was shown before that the laser is able to ablate both carbon fibres and polymeric matrix material, thus, it can be used for scarfing CFRP. However, the ablation process still does not achieve a homogenous surface. For an improved quality and automation of the process the laser scarfing is complemented by short coherent interferometry, a precise distance measurement technique. In this work, an experimental setup is used where short coherent interferometry is performed in-line with the laser scarfing. A comparison is conducted between two approaches; repetitive scarfing and on-axis distance measurements, and repetitive scarfing and off-axis measuring. It is shown that short coherent interferometry is an effective tool to detect the ablation depth, thus enabling homogeneous removal of CFRP for repair preparation.