Damping properties of bamboo and glass fiber reinforced epoxy hybrid composites with edge cracks for vibration damping applications.

Natural fiber thermoplastic composites have gained interest for anti-vibration applications because of their higher specific strength, viscoelastic properties, and better damping ratios. Although some research has looked into the damping ratio of composites, the damping properties of bamboo/glass fiber reinforced epoxy hybrid composites (BGHCs) are still unstudied. This paper examines how fiber weight fraction and crack depth affect the damping ratios of fiber-reinforced hybrid composites made of bamboo and glass with an epoxy matrix. The hybrid composites include bamboo fiber weight fractions of 10%, 20%, and 30%, and glass fiber weight fractions of 10%, 20%, and 30%, all with a consistent 60 wt% epoxy resin. Test specimens with an orientation angle of [00 900 00]s and lamina processing were made using a hand layup-assisted vacuum bagging method and tested according to ASTM E756 standards. The tests involved preparing specimens with edge crack depths of 3 mm, 7 mm, and 11 mm, each with a fixed crack length of 75 mm from the edge. Damping ratios were measured using the half-bandwidth method from the frequency response function graph, recorded with an accelerometer connected to a DAQ NI-6009 during testing. Results showed that the damping ratio decreases as crack depth and glass fiber content increase, while it rises with higher bamboo-glass fiber content. This study offers valuable insights into the damping behavior of BGHC composites with edge cracks, aiding in the design and optimization of components requiring vibration damping and cyclic load resistance.