Photothermal Inspection of Impact Damages on Carbon-Glass Fibre Composites Using a Simple Hand Scanner Measurement System

Abstract

Composite plates having durable and lightweight structure are most interesting materials considering several applications. Because durability is a major criteria, it is important to develop methods for finding flaws that affect this quality. In the case of carbon-glass fibre composites we have earlier demonstrated the suitability of radio frequency (RF) induction heating combined with IR-detection [1]. Based on the good experiences obtained with the method, a suitable equipment for field experiments was developed. Last year we showed the feasibility of a transportable thermal NDT equipment using laser line heating [2]. Modifying this measurement system for RF induction heating, several disadvantages of laser heating can be overcome. In order to test the ability of the system to find flaws in carbon-glass fibre composites, artificial damages simulating impact damages were made to a composite plate. The plate was then inspected using RF induction heating and hand held scanner. MEASUREMENT