Detection of Defects in Kenaf/Epoxy using Infrared Thermal Imaging Technique

Lignocellulosic fibrous polymeric composite materials have become an attractive replacement for heavier metals due to their superior fatigue and corrosion properties. In this study, Infrared (IR) thermal imaging technique has been used to detect the defect in unidirectional Kenaf bast fibre reinforced composite materials. IR thermal imaging technique or IR thermography is a surface thermal radiation measurement technique that is used to detect spatial variations in the measured surface temperature pattern. Thermography reveals flaws by searching anomalous hot-spots after thermal excitation. Thermography can be either categorized as active or passive. An active Infrared thermography has been proven to be a viable non-destructive testing for composite structures. In active thermography the surface of a sample is heated using an external heat source and then the surface temperature is monitored. The thermography analyses were verified by optical microscope and scanning electron microscope (SEM) investigations. The defect detection accuracy of this technique is 95%.