Deep-Trench Structure of Carbon-Fiber-Reinforced Thermoplastics (CFRTP) by Laser Cutting with a Single-Mode IR Fiber Laser.

We report deep-trench microstructures fabricated on carbon-fiber-reinforced thermoplastic (CFRTP; a CFRP containing thermoplastic resin). Well-defined laser cutting free of debris around the trench was achieved for various types of CFRTP plates by single-mode laser irradiation with a fast beam galvanometer scanner using a multiple-scan-pass method. The microfabrication of a CFRTP containing pitch-type carbon fibers and a polycarbonate resin, performed by 600-scan-pass irradiation with a cw kilowatt single-mode IR fiber laser (average power: 1 kW), yielded a trench microstructure with a depth of 18.2 mm and an opening width of 0.32 mm. The laser-induced damage in the samples was analyzed by microscopic X-ray computed tomography. Laser cutting by high-speed beam scanning resulted in a clean top and excellent sidewall quality, along with a negligible heataffected zone. [ABSTRACT FROM AUTHOR]