ABSTRACT
This chapter describes a broader range of porosity dependence for nonmechanical instead of mechanical properties. It demonstrates the diversity of the porosity dependences of nonmechanical properties, ranging from dielectric constant depending only on P, to conductivities depending on MSA, to pore-size effects on some properties, including electrical breakdown, which also depends on oriented pore chains. The chapter introduces basic aspects of surface area and permeability porosity dependences basic to key applications of bodies of designed porosities. It shows that the similarities of the porosity and microcrack dependences of thermal conductivity and that microcracking can result in some porosity and grain-size dependence of thermal expansion. There are four factors that need to be considered in modeling the thermal conductivity of porous materials: two for the solid phase and two for the pore phase. Effects of porosity on thermal conductivity are important in general, especially for ceramics for thermal insulation, usually at higher porosity levels.
