Impact-reduction effect of ultrasonic vibrations on carbon fiber-reinforced polymer plate using a downsized transducer

The number of deaths caused by traffic accidents remains high, in spite of the development of many kinds of safety technologies. It is difficult to absorb the impact energy sufficiently in many cases. We suggested that the impact energy can be further absorbed by adjusting the deformation resistance of the material of the structure instantaneously. Furthermore, we developed an impact-reduction setup by using ultrasonic vibrations. It was already determined in previous studies that the deformation resistance of materials and impact force decrease by applying ultrasonic vibrations. Reducing the weight of vehicles is very significant to improve fuel efficiency. Therefore, we have reported on the deformation and impact-reduction characteristics when a downsized transducer is used. The tested material was high-tensile steel. Carbon fiber-reinforced polymer plate (CFRP plate) is receiving significant attention for the reduction of the weight of vehicles along with high-tensile steel. It is important to confirm the effect of ultrasonic vibrations on the CFRP plate using a downsized ultrasonic transducer. In this study, we used a downsized ultrasonic transducer and measured the vibration, deformation, and impact-reduction characteristics. The CFRP plate can be bent easily with the application of ultrasonic vibrations. The time elapsed before the specimens were fractured was reduced with the increase in the driving voltage. The impact force was reduced by up to 82.3% with the application of ultrasonic vibrations.