Thermal and mechanical properties of AlSi7Mg matrix syntactic foams reinforced by Al$_2$O$_3$ or SiC particles in matrix

Abstract: Materials with complex inner structure can be challenging to characterize in an effective way. First, it is difficult to determine the representative volume for such a heterogeneous material. Second, the effective material parameters significantly depend on the structure, and thus on the interface properties. In the present paper, we focus on composite metal foams, and we attempt to determine the effective thermal parameters. We use the heat pulse experiment to study its transient thermal response. We observed deviation from Fourier's law, and thus we propose an evaluation procedure for such experimental data using the Guyer--Krumhansl heat equation. Furthermore, we studied the effective parameters, the specific heat, mass density, thermal conductivity and thermal diffusivity, and we propose a method for deducing a more reliable thermal diffusivity and thermal conductivity based on the transient temperature history.