Novel mullite‐cordierite ceramic refractory fabricated from halloysite and talc

This research work aims to fabricate industrial refractory bricks using cheap and abundant kaolin DD 3 constituted of Halloysite. The fabrication process consists on mixing the crushed raw materials (Kaolin/Clay, Fireclay, Talc) with the respective proportions and an optimized granulometry, shaped by a uniaxial hydrostatic pressure of 250 bars, followed by drying at 100°C and sintering at 1300°C. The addition of Talc ‐ at first with water, Fireclay and AP/DD 3 ‐ as a source of MgO promotes the increase of Cordierite formation ( S i O 2‐ A l 2 O 3 ‐ M g O ) in order to obtain high heat resistance shock and reduced thermal expansion. Three assays are studied with AP Clay and DD 3 Kaolin weight ratios (100/0, 50/50 and 0/100) % corresponding to (ER 0 , ER 1 and ER 2 ) respectively. Mineralogical analysis results of the new refractory bricks, indicate the presence of Mullite and Cordierite as major phases besides Corundum and Quartz as minor phases. All products (ER 0 , ER 1 and ER 2 ) are found to be argillaceous refractory with Alumina concentration (40 < Al 2 O 3 < 45%, FC 40 group) and a melting point higher than 1600°C. The mechanical resistance of the samples is of the same order of magnitude; reaching 51 MPa.