Novel Synthesis of Microporous Mica Ceramics Using Alumina-Pillared Fluorine Micas by Pulse Electric Current Sintering

抄録

Unique mica ceramics with micropores were fabricated from alumina-pillared fluorine micas by pulse electric current sintering (PECS) at a temperature range of 600-800°C under a uniaxial pressure range of 10-30 MPa. The effects of PECS conditions and the nature of alumina-pillared mica powders on the formation and properties of the mica ceramics were studied. The mica ceramics obtained at lower temperatures and lower uniaxial pressures retained the pillared structure of alumina-pillared micas and gave a maximum BET specific surface area of ∼300 m² g^-1, while those obtained at higher temperatures and higher uniaxial pressures lost the pillared structure and microporous characteristics. The mica ceramics thus obtained were machinable due to the interlocking microstructure of the flaky pillared mica crystals. Fully densified mica ceramics could be also produced by PECS at ∼1035°C under a uniaxial pressure range of 10-30 MPa.