The Effect of Fiber Orientation on the Dynamic Characteristic of the Carbon – Glass Fiber Hybrid Composite

Abstract

This resarch is to study the effect of the fiber orientation on the dynamic characteristic of the carbon-glass fiber hybrid composite. The dynamic charactristics studied was damping ratio and natural frequency. The hybrid composite was made by hand lay up medtod using volume fraction of 0.4 and dimension of 250 x 40 x 3 mm. Fiber orientations used in this experiment were 0 o /90 o , 30 o /60 o , and 45 o /45 o . The vibration experiment was done by giving excitation to the composite specimen using impact hammer and the vibration response was obtained from the accelerometer attached on the specimens. Three type of the supported beam configurations used in this experiment, i.e: cantilever beam, simple supported beam, and fixed supported beam. The experiment results showed that the fiber orientation affects to the dynamic characteristics of the carbon-glass fiber hybrid composite. This is due to the flexular rigidity of the composites. Fiber orientation of 0 o /90 have the highest flexular rigidity, so it have high natural frequencies at all beam configuration in compare to the other fiber orientation. Its natural frequencies at at the configuration cantilever beam, simple supported beam, and fixed beam are 39 Hz, 105 Hz, and 261 Hz respectively. Damping ratio behave in opposite way to the natural frequency, carbon-glass fiber hybrid composite which low rigidity i.e. fiber orientation of 45/45 gives high damping ratio in all beam configuration, and the highest is 0.0038 found in cantilever beam configuration.