Effect of double-diffusive heat transfer on thermal conductivity of porous sintered ceramics: Macrotransport analysis

Heat conduction in composite materials has been traditionally considered as occurring via conductance through the solid phase and also in pores containing gas. In this paper these mechanisms are considered together with thermal effects associated with motion of mass species – impurities, or lattice defects, normally present in all sintered ceramic materials. Diffusion and reversible segregation and desegregation of these species (from solid bulk to pore surfaces and back), is induced by an externally applied temperature gradient and accompanied by heat release and absorption on pore surface.