Study on ultrasonic vibration-assisted adhesive bonding of CFRP joints

As adhesive bonding does not disrupt the continuity of the fiber integral, it has become an important bonding method of CFRP (carbon fiber-reinforced plastics) joints. Regarding the quality problems in the traditional adhesive bonding process, i.e. the low and unstable adhesion strength, a novel ultrasonic vibration-assisted adhesive bonding method for CFRP joints is proposed. In this method, extra force caused by ultrasonic vibration is introduced into the bonding process to reinforce it. The strengthening mechanism is then analyzed. According to our study, it is found that: (1) ultrasonic vibration can improve the adhesion strength and stability by 52 and 66% in the test. (2) The strengthening mechanism is summarized as: high-frequency vibration contact between adhesive and wall is produced under ultrasonic vibration, which forms better contact; adhesive is driven to penetrate into the surface roughness of the bonding area under ultrasonic vibration, which increases the effective bonding area.