Numerical Simulation of Saturation Behavior of Physical Properties in Composites with Randomly Distributed Second-phase

Second-phase materials are generally added to a matrix material in order to improve its physical properties. To enhance the thermal conductivity and stiffness of a polymer material, some powders and/or short-fibers are used. Physical properties such as thermal conductivity and elastic modulus of the composites with randomly distributed second-phase are computed by the use of the finite element methods and verified by experimentation. The computation results show that there exists a saturated property ratio of the second-phase to the matrix at a certain volume fraction. The saturated ratio increases with the increase of volume fraction and the fiber length to diameter ratio. Beyond this saturated ratio, the physical properties of the composite cannot be further improved by enhancing the corresponding property of the second-phase material. A comparison with other analytical models indicates that some models may predict the saturation behavior well while some others may not.

[1]  Jacqueline J. Li,et al.  Effective elastic moduli of composites reinforced by particle or fiber with an inhomogeneous interphase , 2003 .

[2]  The Effective Conductivities of Composites with Cubic Arrays of Spheroids and Cubes , 1999 .

[3]  S. Nemat-Nasser,et al.  Micromechanics: Overall Properties of Heterogeneous Materials , 1993 .

[4]  Daining Fang,et al.  Elastic and plastic properties of metal-matrix composites: geometrical effects of particles , 1996 .

[5]  C. Tang,et al.  Finite element analysis of polymer composites filled by interphase coated particles , 2001 .

[6]  S. Cheng,et al.  The prediction of the thermal conductivity of two and three phase solid heterogeneous mixtures , 1969 .

[7]  Shangdong Tu,et al.  Thermal Conductivities of PTFE Composites with Random Distributed Graphite Particles , 2002 .

[8]  W. Voigt,et al.  Lehrbuch der Kristallphysik , 1966 .

[9]  M. W. Darlington,et al.  Fibre orientation distribution in short fibre reinforced plastics , 1975 .

[10]  H. W. Russell PRINCIPLES OF HEAT FLOW IN POROUS INSULATORS , 1935 .

[11]  Y. Agari,et al.  Estimation on thermal conductivities of filled polymers , 1986 .

[12]  V. Ervin,et al.  Finite-element modeling of heat transfer in carbon/carbon composites , 1999 .

[13]  L. Nielsen Generalized Equation for the Elastic Moduli of Composite Materials , 1970 .

[14]  Shih‐Yuan Lu,et al.  Anisotropy in effective conductivities of rectangular arrays of elliptic cylinders , 1994 .

[15]  K. Kondo,et al.  Moisture Diffusivity of Unidirectional Composites , 1982 .

[16]  A. Reuss,et al.  Berechnung der Fließgrenze von Mischkristallen auf Grund der Plastizitätsbedingung für Einkristalle . , 1929 .

[17]  S. Tsai,et al.  Introduction to composite materials , 1980 .

[18]  M. Schwartz Composite Materials Handbook , 1984 .

[19]  M. Hashimoto,et al.  Transient Characteristics of Thermal Conduction in Dispersed Composites , 1998 .

[20]  M. Islam,et al.  Thermal Conductivity of Fiber Reinforced Composites by the FEM , 1999 .

[21]  Jiann-Wen Ju,et al.  Micromechanics and effective moduli of elastic composites containing randomly dispersed ellipsoidal inhomogeneities , 1994 .

[22]  Shih‐Yuan Lu,et al.  The Effective Thermal Conductivities of Composites with 2-D Arrays of Circular and Square Cylinders , 1995 .