Experimental Investigations on Thermo-mechanical Behavior and Failure Mechanisms of Hybrid Bonded-bolted Plain-woven Composite Joint

This paper focuses on the thermo-mechanical coupling behavior and failure mechanisms of singlelap bonded, bolted, and hybrid bonded-bolted plain-woven composite joints. Quasi-static tension tests were conducted on these three types of joints at -50 degrees C, -20 degrees C, +23 degrees C, +70 degrees C and +120 degrees C, respectively. Based on the experimental results, the failure mechanisms and hybridization effect of the hybrid joint under temperature impact were analyzed and discussed. It is shown that i) failure load in the bonding stage of the hybrid joint is significantly lower than that of the bonded joint. ii) The increasing temperature not only leads to the decreasing joint performances of joints but also the transition of failure modes for the bonded joint and hybrid joint. iii) Compared with the bonded joint and bolted joint, no significant improvement is observed in the joint strength and joint stiffness of the hybrid joint, which is due to the high stiffness of the adhesive and the thread embedment-induced adhesive failure. iv) Although the hybridization effect is not sensitive to the temperature of -50 degrees C and -20 degrees C, it shows a strong relation with the temperature of +120 degrees C, which is probably due to the premature adhesive failure.