Low energy impact damages detection in carbon fibre reinforced carbon using ultrasonic – Stimulated infrared thermography

Carbon-carbon composites, or more precisely, carbon fibre reinforced carbon (C/C) are composed of carbon fibres in a carbon matrix. They are lightweight materials that can perform structurally at extreme temperatures and have superior thermal shock, toughness, ablation, and high-speed friction properties. C/C is widely use in aerospace and defence industries. However, like other composite, it is also sensitive to impact damage, therefore detecting damages in C/C is important for ensuring the structural integrity and safety. This paper presents an application of a novel non-destructive testing called Ultrasonic-stimulated Infrared Thermography (UIT) for a real-time impact damage detection in C/C. In this study, a short ultrasonic pulse (15 s) is applied to C/C plate which contained 6 artificial low energy impact damages. An infrared (IR) camera is used to observe and record the temperature change. From a sequence of thermogram, the defective area can be detected easily. The study demonstrates that UIT can successfully reveal the low energy impact damage in carbon composite structure or component.