Damage Detection and Evaluation on Gamma Irradiated Oil Palm EFB/Kevlar Hybrid Composites Using NDT Methods

The aim of this work is to evaluate the low-velocity impact damages on gamma irradiated Kevlar/oil palm empty fruit bunch (EFB) hybrid composites. Doses of 25 kGy, 50 kGy and 150 kGyof gamma radiation were applied to the sample. The samples were impacted at seven energy levels using a drop weight machine. Computed tomography (CT), ultrasonic testing (UT) and acoustic emission (AE) methods were applied on the samples. It was found that the UT method was not suitable to detect the impact damage for the samples due to the characteristics of the oil palm fibre. CT and AE methods were able to detect matrix cracking, delamination and fibre breakage in the hybrid composites.