Lamb wave inspection of composite materials with fiber Bragg grating-based sensors

Abstract

Nowadays, the aerospace industry is in need of a non-destructive testing technique to inspect composite laminates efficiently. In this master thesis we have performed ultrasonic Lamb wave inspection on a carbon fiber reinforced plastic (CFRP) plate with fiber Bragg grating-based sensors embedded in the mid-plane during the curing process of the plate. A tunable laser interro-gation system was built to interrogate these fiber optic strain sensors while Lamb waves were excited by a piezoelectric transducer. We detected and located damage in a CFRP plate for the first time through the use of embedded FBG strain rosettes. We also evaluated the potential of us-ing microstructured optical fiber Bragg gratings to detect Lamb waves in a CFRP plate, with the potential to extract multidimensional information from Lamb waves. These innovative sensors open perspectives in applying simplified and multi-strategic damage detection and localisation techniques.

Date of Award	Jun 2016
Original language	English
Supervisor	Ben Dieter De Pauw (Promotor) & Sidney Frans Goossens (Promotor)