Portable Automated Radio-Frequency Scanner for Non-destructive Testing of Carbon-Fibre-Reinforced Polymer Composites

Abstract

A portable automated scanner for non-destructive testing of carbon-fibre-reinforced polymer (CFRP) composites has been developed. Measurement head has been equipped with an array of newly developed radio-frequency (RF) inductive sensors mounted on a flexible arm, which allows the measurement of curved CFRP samples. The scanner is also equipped with vacuum sucks providing mechanical stability. RF sensors operate in a frequency range spanning from 10 up to 300 MHz, where the largest sensitivity to defects buried below the front CFRP surface is expected. Unlike to ultrasonic testing, which will be used for reference, the proposed technique does not require additional couplants. Moreover, negligible cost and high repeatability of inductive sensors allows developing large scanning arrays, thus, substantially speeding up the measurements of large surfaces. The objective will be to present the results of an extensive measurement campaign undertaken for both planar and curved large CFRP samples, pointing out major achievements and potential challenges that still have to be addressed.

A method and apparatus for inspecting large flat composite parts by using the Infrared LST technique

“…The principle of induction heating in TNDT was used by Thomas and Balasubramaniam [19]. A portable radio-frequency scanner was described by Salski et al for inspecting composites [20]. An infrared inspection system called a "thermal photocopier" was proposed by Woolard and Cramer [21].…”

Combined US and UWB-RF imaging of concrete structures for identification and location of embedded materials

“…Alternatively, full transmission assessment has also been addressed for RF inspection. Despite early attempts [16] only marginally have been reported until very recently [17][18][19][20][21]. These still focus on differences in attenuation due to material-specific electric permittivity; just as ultrasonic inspection does for acoustic impedance.…”