A study of damping characteristics of alumina-filled epoxy nano-composites

Damping behavior of polymeric composites with nano structured phases is significantly different from usual polymer composites. Viscoelastic homopolymers exhibit high material damping over a relatively narrow range of temperature and frequencies. In many practical situations a polymeric structure is required to possess better strength and stiffness properties together with a reasonable damping behavior. Viscoelastic polymers show higher loss factor beyond the glassy region which comes with a significant drop in the specific modulus. Addition of nano alumina particles to epoxy leads to improved strength and stiffness properties with an increase in glass transition temperature while retaining its damping capabilities. Experimental investigations are carried out on composite beam specimen fabricated with different volume fractions of alumina nano particles in epoxy to determine loss factor, tan δ. Impact damping method is used for time response analysis. A single point Laser is used to record the transverse displacement of a point on the composite beam specimen. Experimental results are compared with theoretical estimation of loss factor using Voigt estimation. The effect of interphase is included in theoretical estimation of loss factor. Passive vibration suppression may be introduced in the polymeric structures along with improved structural properties by tailored dynamic characteristics using nano alumina particle filled epoxy composites.

[1]  R. Christensen,et al.  Viscoelastic properties of heterogeneous media , 1969 .

[2]  T. Shimogo.  Vibration Damping , 1994, Active and Passive Vibration Damping.

[3]  Wanbo Liu,et al.  Experimental and analytical estimation of damping in beams and plates with damping treatments , 2008 .

[4]  Nikhil Koratkar,et al.  Viscoelasticity in carbon nanotube composites , 2005, Nature materials.

[5]  Alberto Castellani,et al.  Vibrations Generated by Rail Vehicles: A Mathematical Model in the Frequency Domain , 2000 .

[6]  Y. S. Tarng,et al.  A study of the active vibration control of a cutting tool , 1999 .

[7]  Zvi Hashin,et al.  Complex moduli of viscoelastic composites—I. General theory and application to particulate composites , 1970 .

[8]  M. Bakar,et al.  Properties of Epoxy Based Hybrid Composites , 2005 .

[9]  Bishakh Bhattacharya,et al.  A finite element based investigation on obtaining high material damping over a large frequency range in viscoelastic composites , 2007 .

[10]  M. Sumita,et al.  Characterization of the vibrational damping loss factor and viscoelastic properties of ethylene-propylene rubbers reinforced with micro-scale fillers , 2001 .

[11]  Zvi Hashin,et al.  The Elastic Moduli of Heterogeneous Materials , 1962 .

[12]  A. Omrani,et al.  Understanding the effect of nano-Al2O3 addition upon the properties of epoxy-based hybrid composites , 2009 .

[13]  J. Ferry,et al.  Mathematical Structure of the Theories of Viscoelasticity , 1955 .

[14]  Zvi Hashin,et al.  Viscoelastic Behavior of Heterogeneous Media , 1965 .

[15]  Roderic S. Lakes,et al.  Viscoelastic Solids (1998) , 1998 .

[16]  David Hui,et al.  Advanced shock-resistant and vibration damping of nanoparticle-reinforced composite material , 2008 .

[17]  K. Friedrich,et al.  Epoxy/alumina nanoparticle composites. I. Dynamic mechanical behavior , 2003 .

[18]  James M. Kelly,et al.  Experimental testing of a semi-active control scheme for vibration suppression , 1997, Smart Structures.

[19]  李黎,et al.  Stochastic seismic response of structures with added viscoelastic dampers modeled by fractional derivative , 2003 .