... walls0.7 mm0,028 inSpec. area825 m²/m³251.4ft²/ft³Void fraction64%64% Physical dataNameUnitAlumina PorcelainMullit porousCordieriteDenseCordierite PorousQuartz PorcelainDensityg/m ... ,2430,203Heat conductivityW/mK2,502,421,891,631,5BTU in/ft² hr°F17,316,813,111,310.4Temperature changeResistancemax K500550500600500max °F9009909001080900Softening ...