ASTM C1274-12

1.1 This test method covers the determination of the surface area of advanced ceramic materials (in a solid form) based on multilayer physisorption of gas in accordance with the method of Brunauer, Emmett, and Teller (BET) (1)² and based on IUPAC Recommendations (1984 and 1994) (2) and (3). This test method specifies general procedures that are applicable to many commercial physical adsorption instruments. This test method provides specific sample outgassing procedures for selected common ceramic materials, including: amorphous and crystalline silicas, TiO₂, kaolin, silicon nitride, silicon carbide, zirconium oxide, etc. The multipoint BET (1) equation along with the single point approximation of the BET equation are the basis for all calculations. This test method is appropriate for measuring surface areas of advanced ceramic powders down to at least 0.05 m²  (if in addition to nitrogen, krypton at 77.35 K is utilized as an adsorptive).