Quality analysis of 2D and 3D-draped carbon preforms by eddy current scanning

This paper investigates the change in yarn orientation during the step-wise deformations by 3D-draping and shearing process of biaxial carbon-fiber non-crimp fabrics as the principal objective. At each step, the yarn orientation in the fabric was measured by a robot-guided eddy current scanning system which was also effective to detect some faults to aid in the quality assurance of the carbon preforms. Besides, shearing at certain levels and beyond gives unwanted wrinkles which were detected by eddy current scanning. This scanning process was also applied to detect thermoplastic binders along with binder order analysis and presence of stitching yarns on carbon preforms or composites. The detection system gave satisfactory result to the quality assurance process of carbon preforms and carbon fiber reinforced plastic composites (CFRP).