Chirped fibre Bragg grating (CFBG) sensors have been embedded in composite coupons which have been used to form one half of single lap bonded joints. The bonded joints have been made with deliberately included defects, consisting of either a PTFE insert or an air gap, and the sensors have been used to detect the presence and location of the defects. The experimental results, and the modelling, show that defects in both GFRP-GFRP joints and CFRP-CFRP joints can be detected by the embedded CFBG sensors, though it is easier to detect defects in the lower stiffness (GFRP) joints.
Abstract. Chirped fiber Bragg grating (CFBG) sensors were embedded within the adhesive bondline of single-lap CFRP-GFRP bonded composite joints. The effect of disbond propagation (as a consequence of fatigue loading) on the reflected spectra from the CFBG sensor has been studied. As the disbond propagates, thermal strains generated during the bonding of the joint at elevated temperature are released and, as a consequence, a peak in the reflected spectra of the CFBG sensor can be seen. Using a transparent GFRP adherend, it has been possible to demonstrate that there is reasonable agreement between the position of the peak in the reflected spectrum and the disbond front position in the bonded joint.
In this work, the dyeing methods with ultrasonic technology and tradition method were investigated. Dye uptake and rubbing fastness as detection index of feather fibers were analysed. The optimum conditions of dyeing in feather fibers with ultrasonic wave technology were determined: weak acid dye: dyeing temperature 70°C, time 40min; reactive dye: dyeing temperature 90°C, time 50min. The results showed that in this dyeing conditions, dye uptake using ultrasonic technology can reach 89.9%, that increased 31.9% comparing with that using traditional method; rubbing fastness can be over 3 grade, and the dry rubbing fastness was raised by 0.5~1 grade as compared with the wet rubbing fastness. It was found that the effect of dyed feather fibers can be better by using ultrasonic technology, which were eco friendly and so give good effect to human in addition to values on garments, and provided the beneficial to test for development of feather fibers.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.