RT - Journal Article T1 - Investigating the Vibrational and Damping Properties of Graphite Nano - Platelet/Epoxy Composites JF - mdrsjrns YR - 2019 JO - mdrsjrns VO - 19 IS - 9 UR - http://mme.modares.ac.ir/article-15-25163-en.html SP - 2263 EP - 2271 K1 - Epoxy K1 - Graphite Nano-Platelet K1 - Vibration K1 - Damping K1 - Representative Volume Element (RVE) AB - In the present study, the effect of graphite nano platelet (GNP) as a filler on the vibrational properties of the epoxy EP411 DSM matrix was studied. For this purpose, GNP-epoxy composites samples were fabricated with 0-5 wt.% of GNPs using the solution mixing method. Free and forced vibrations tests on the cantilever composite specimens were conducted. Based on the free vibration results, the structural damping loss factor η was obtained as a function of the GNP loading. It was found that η decreases as the GNP wt.% increases and reaches to the lowest value at 0-3 wt.% of GNP content, and increases as the GNP loading increases and reaches to the value at 3-5 wt.% of GNP. Also, the frequency response function (FRF) around the second vibration mode was obtained for the neat epoxy. The Rayleigh damping coefficients were calculated employing the free and forced vibration results. The results revealed a nonlinear dependence of damping ratio η on the natural frequency of the neat epoxy. A representative volume element (RVE) incorporating 0-5 wt.% of GNPs was generated and the vibrational properties were numerically simulated. The modeling results were compared with those obtained from the experiment to verify whether the basic assumptions had been chosen properly. LA eng UL http://mme.modares.ac.ir/article-15-25163-en.html M3 ER -