Aerospace composites detection

The performance of the classifier has been verified using a number of practical applications, such as civil engineering [3], inspection of aerospace composite structures, ball bearings and aircraft multi-layer structures. Here we present shortly some results, focusing on detection of disbonds in adhesively joint multi-layer aerospace structures using Fokker Bond Tester resonance instrument, details can be found in [1]. 

NQR (a proprietary type) is being investigated for use to detect strains that may develop in aerospace composite stractures before these stmctures can fail and lead to crashes. 

Ecault, R., Boustie, M., Berthe, L., Touchard, F., Voillaume, H., Campagne, B. and Loison, D. (2013) Development of a laser shock adhesion test for the detection of weak composite bonds, Proceeding of the 5th International Symposium on NDT in Aerospace, Singapore, November 13-15. 

The two major categories of polymer composite used in aerospace are laminates and sandwich stmctures, which require some differences in NDT inspection methods. The inspection of choice at the time of manufacture may be different from the inspection of choice for in-service assessments. The form of the stmcture determines the types of features of concern and the NDT techniques that may be apphed to detect and measure them. Table 15.1 summarizes some general thoughts and considerations on NDT of polymer composite stmctures. American Society for Testing and Materials (ASTM) also provides guidance on NDT for polymer composites [12]. The primary concerns in laminates are voids and porosity, inclusions, delamination, the fiber-to-resin ratio, and wrinkles (wavy or out-of-plane ply). Ultrasound is the predominate method for composite laminate inspection. In sandwich structures, the core material-to-facesheet bond, core condition, and fluid ingress are the usual concerns. 

Smart skin (smart composite) n. A composite containing molded-in sensors and micro transmitters that enable aerospace engineers to detect in-flight changes in temperature, strain, ice thickness, and cracks. 

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