Thermal Conductivity of the In-Situ Type AlN-Al-AlB₁₂ Composite

Abstract

  Thermal conductivity of the in-situ type AlN-Al-AlB₁₂ ternary composite, which was synthesized with the aid of the exothermic reaction between molten Al and BN powder, has been studied. Although the thermal conductivity of this composite is certainly raised with an increase in AlN concentration, it significantly degenerates due to the existence of voids. The compound AlB₁₂, which is uncalled-for product to our composite, may also lower the composite thermal conductivity. The void volume fraction in the composite is fairly decreased by flowing the atmospheric fresh N₂ gas into the reaction chamber. Negative effect of voids to the composite thermal conductivity has been discussed.