Aluminum Nanocomposite based on Ensemble of Carbon Materials for Enhanced Vibration Damping

Many aluminum nanocomposites consisting of a single particulate phase have been synthesized and tested in the past. However, vibration damping characteristics of aluminum nanocomposite based on ensemble or combination of two morphologically different carbon-based materials have not been reported. Therefore, in this work the focus is to synthesize an aluminum nanocomposite based on the combination of two different carbon-based particulate phases namely graphite flake and carbon fiber in order to identify any improvement in the damping ability of the as-synthesized aluminum nanocomposite material. Aluminum nanocomposite was prepared using stir casting method. The particulate phases of carbon were used in varying weight compositions but were always in an equal ratio relative to each other. The material was casted in form of thin rectangular bars using metallic dies and tested in a cantilever beam configuration. MEMS based accelerometer via Arduino microcontroller was used to collect the time dependent response at the free end of the beams. The damping constant ζ was estimated from the response curves. Experiments indicate that compared to the pristine aluminum bars, the damping ability of the as-synthesized aluminum nanocomposite increases by almost 117 % at 3 wt% of the particulate phase. The increase in damping is mainly attributed to the trans-granular frictional effects and weak interfacial bonding between the metal matrix and the particulate phases. Aluminum nanocomposite is successfully prepared using combination of two morphologically different carbon-based particulate phases. The as-synthesized material shows favorable damping performance that can be exploited in structural, automotive, marine and aerospace applications.