Vibration damping using flexible graphite

Vibration damping is valuable for structures, as it material for high temperature or chemically harsh environ-mitigates hazards (whether due to accidental loading, wind, ments. ocean waves or earthquakes), increases the comfort of Due to its resilience, in addition to its thermal resistance, people who use the structures, and enhances the reliability chemical resistance, low thermal expansion and high and performance of structures. The basic concept about thermal conductivity, flexible graphite was investigated in damping involves the absorption of external energy this work for use in vibration damping. The investigation through internal motion or friction [1,2]. A layered struc- involved simultaneous measurement of the loss tangent ture is attractive for damping due to the large internal (tan d, i.e. damping capacity) and storage modulus (stiff-surface area involved [3,4]. The relative motion between ness) under dynamic flexure (three-point bending at a very layers produces extra shear, which means more energy small deflection amplitude) at fixed frequencies. The dissipation [5]. For instance, a viscoelastic material or a product of loss tangent and storage modulus is the loss fluid layer is sandwiched within a beam for both passive modulus. As high values of both loss tangent and storage and active damping [6–8]. However, fluid and viscoelastic modulus are desired for vibration reduction, a high value materials suffer from their poor stiffness, limited resistance of the loss modulus is desired. Rather low frequencies are to heat and chemicals, in addition to high thermal expan- used in this study due to their relevance to the vibration o