GB1362626A - Ceramic materials - Google Patents

Abstract

1362626 Cordierite bodies COMMONWEALTH SCIENTIFIC & INDUSTRIAL RESEARCH ORGANIZATION 17 Aug 1972 [27 Aug 1971] 38421/72 Heading C1J A composition comprises a mixture of clays or other ceramic raw materials whose molecular proportions are substantially equivalent to those of cordierite together with 8-12 weight per cent of potash feldspar, a mixture of nephelinesyenite and whiting, or Na2O.TiO2.SiO2. The above composition when made by first mixing the clays or other ceramic raw materials and then adding the 8-12 wt. per cent of mineralizer, may be fired at below 1350‹ C. to produce a self surface glazed ceramic body of substantially cordierite structure. Oxide compositions of the first mixture may be 56-48 wt. per cent SiO2, 23-38 wt. per cent Al2O3, and 10À5-18À5 wt. per cent MgO. Colouring of these glazes may be by incorporation of ceramic chromophones into the mixture prior to shaping or by spraying soluble metallic salts (e.g. Fe<3+> or CO<3+> saltssome CO<3+> salts may produce the blue spinel MgCOAl2O4). Compositions of puggoon clay, ball clay and talc (optionally precalcined) are given to illustrate first mixtures.