LOW CTE CORDIERITE BODIES WITH NARROW PORE SIZE DISTRIBUTION AND METHOD OF MAKING SAME

摘要

Cordierite body of CTE at 25-800 °C of ≤4 x 10-7C-1, at least 85 % of porosity having pore diameter of 0.5-5.0ν: or ⊃4-6 x 10-7C-1, porosity at least 30 vol %, at least 85 % of porosity has pore diameter 0.5-5.0ν. Raw materials talc, A1¿2?O3 source, and kaolin, calcined kaolin, and/or silica, and optionally spinel, particle diameter of talc ≤ 3.0ν, of A12O3 source ≤ 2.0ν, kaolin is ∫ 35 wt % of raw materials when particle diameter is ∫ 2.0ν, are blended with vehicle and aids into plastic mixture. Green body is formed, dried, fired at 1370 °C-1435 °C. When particle diameter of talc is ∫ 2.0ν, and A12O3 source is ∫ 20 wt % of raw materials, and dispersible high surface area A12O3 source having particle diameter of ∫ 0.3ν, is ∫ 5.0 wt % of raw materials, and particle diameter of kaolin is ∫ 2.0ν, heating rate from 1150 °C-1275 °C is ⊃ 200 °C/hr. When particle diameter of talc is ≥ 2.0ν, and A12O3 source is ∫ 20 wt % of raw materials, and dispersible high surface area A12O3 source having particle diameter of ∫ 0.3ν, is ∫ 5.0 wt % of raw materials, and particle diameter of kaolin is ∫ 2.0ν, heating rate from 1150 °C-1275 °C is ⊃ 50 °C/hr and ∫ 6000 °C/hr. When A12O3 source is less than 20 wt % of raw materials, and dispersible A12O3 source having particle diameter ∫ 0.3ν is ≥ 5.0 wt % of raw materials, and particle diameter of kaolin is ∫ 2.0ν, heating rate from 1150 °C-1275 °C is ⊃ 50 °C/hr. When particle diameter of kaolin is ⊃ 2.0ν, heating rate from 1150 °C-1275 °C is ∫ 600 °C/hr and ⊃ 30 °C/hr.