Impact strength improvement of adhesively bonded structures using natural date palm tree fibers

Four different types of natural date palm tree fibers (DPTFs), including Rachis, Petiole, Bunch, and Mesh, were used as short fibers added to single lap adhesive joints subjected to quasi static and impact loading. The results show that the fibers have a remarkable effect on the static and impact strengths of the joints. Adding 2 wt% and 5 wt% of Bunch fibers to the adhesive layer impressively increased the impact strength by 196% and 62%, respectively. The analysis of fracture surfaces showed that DPTFs make the crack propagation more stable and increase the strength and the damping capacity of the joints.