Development of Ultrasonic-Polarized Mechanism for Stacking Orientation of Quasi-Isotropy Composite Laminates

Abstract

Composite laminates help to lighten components because they have the advantage of higher strength-to-weight ratio. So, they have come to be utilized as parts of advanced areas. An NDE technique for stacking orientation determination would be very beneficial because of layup orientation influence to the laminate stiffness. In this study, an investigation of shear wave ultrasonic technique was carried out in order to detect stacking orientation error for quasi-isotropy composite laminates. During testing, the most significant problem is that the couplant conditions do not remain the same because of changing the viscosity of the couplant. Therefore, the design and use of a shear wave transducers would greatly aid in alleviating the couplant problem. A pyramid with an isosceles triangle with two 45o was made of aluminum to generate shear waves using two longitudinal transducers based on ultrasonic-polarized mechanism. Also, the signal splitter was connected to the pulser jack on the pulser/receiver and to the longitudinal transducers. The longitudinal transducers were mounted with mineral oil and the shear transducer was mounted on the bottom as a receiver with burnt honey. It is found that the shear wave was generated at a maximum and a minimum based on the ultrasonic-polarized mechanism. To apply this method into a practical inspection tool, the quasi-isotropy composite laminates were nondestructively evaluated for detecting error of the laminates.