摘要 |
A ceramic comprising predominately a cordierite-type phase approximating the stoichiometry Mg<SUB>2</SUB>Al<SUB>4</SUB>Si<SUB>5</SUB>O<SUB>18 </SUB>and having a coefficient of thermal expansion (25-800° C.) of greater than 4x10<SUP>-7</SUP>/° C. and less than 13x10<SUP>-7</SUP>/° C. and a permeability and a pore size distribution which satisfy the relation 2.108 (permeability)+18.511 (total pore volume)+0.1863 (percentage of total pore volume comprised of pores between 4 and 40 micrometers)>24.6. The ceramic is suitable in the fabrication of cellular, wall-flow, diesel particulate filters having a pressure drop in kPa that at an artificial carbon soot loading of 5 grams/liter and a flow rate of 26 scfm is less than 8.9-0.035 (number of cells per square inch)+300 (cell wall thickness in inches), a bulk filter density of at least 0.60 g/cm<SUP>3 </SUP>and a volumetric heat capacity of at least 0.67 J cm<SUP>-3 </SUP>K<SUP>-1 </SUP>as measured at 500° C.
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