Non-destructive characterization of smart CFRP structures

Abstract

Smart materials based on carbon-fibre-reinforced plastic (CFRP) with embedded PZT sensors and actuators are expected to be a favourite composite for vibration damping and noise reduction. Due to the wide variety of physical properties of the components, various damage mechanisms may reduce or even remove the sensing and actuating capabilities of the piezoceramic material. Comprehensive non-destructive characterization and integral health monitoring help to optimize the structure and its manufacturing and are essential prerequisites to ensure performance and availability of smart components during their lifetime. The first part of the paper presents high-resolution non-destructive imaging methods including microfocus x-rays, ultrasonics and eddy currents. These methods are used to characterize damage resulting from non-optimal manufacturing and external load. The second part is dedicated to newly developed imaging techniques using the active piezoceramics as transmitters of acoustic, electromagnetic and thermal fields. The third part focuses on health monitoring by impedance spectroscopy using the same piezoceramics as for vibration damping. Electromechanical finite-element modelling and experimental investigations of strip-shaped specimens have shown the close connection between mechanical properties and electrical impedance.

Nondestructive Testing of Polymers and Polymer–Matrix Composites

“…395. Piezoelectric thin wafers or plates (396) or active fiber composites made from piezoelectric fibers (397) also yield, for example, strain and acoustic emission signals. The performance of fiber optics and piezoelectric sensors for detection of microscopic damage in CFRP is compared in Ref.…”

High-resolution eddy current sensor system for quality assessment of carbon fiber materials

“…Discontinuities can be located in different layers of RCF and also in the laminated material (c.f. Mook et al 2003). The EC-Images and EC-Phase Images represent integral information on material characteristics.…”

Electromagnetic configurable architectures for assessment of Carbon Fiber Reinforced Plastics

“…Due to the numerous types of layups and layouts in configuring the composites in function of layers number, orientation of fibers and woven, type of matrix, etc., the full effect of design over the behavior of the composites at impact isn't yet elucidated, different designs leading to the development of different control methods [13,14]. Taking into studies samples of CFRP, usually used in aerospace engineering, carbon fiber embedded in Polyphenylene sulphide (PPS) matrix, this paper present a novel type of electromagnetic sensors defined as CA due to the possibility to interrogate only a part of the sensors from the architecture or the entire assembly, to detect damages induced by low energy impact, increasing the spatial resolution compared to the classical sensors.…”