Effective thermal properties of an aluminum matrix composite with coated diamond inhomogeneities

Abstract

The paper focuses on the calculation of the effective thermal properties of aluminum matrix composites containing diamond particles. We propose a model explaining non-monotonic behavior of the overall thermal conductivity (TC) and monotonic behavior of the thermal expansion coefficient (CTE) at high volume fraction of diamond particles. The model also accounts for the effect of particle coatings that increases the interfacial bonding between the diamond particles and metal matrix. Effect of the coating is modeled using differential method of replacing an inhomogeneous inclusion by an equivalent homogeneous one. The effective properties are calculated using Maxwell homogenization scheme and compared with experimental data. We also establish and verify experimentally cross-property connection between thermal conductivity and thermal expansion coefficient for Al\\diamond composites.