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This study was aimed to investigate the key properties, mullite formation and glaze-body fit of sanitary ware bodies, by using pottery stone from Lampang, Thailand as a substitute for kaolin, feldspar, and silica. Seven samples of formulated bodies were prepared by wet milling, formed by plaster mold casting, and fired at 1175 °C, 1200 °C, and 1225 °C. Testings were carried out in accordance with ASTM C373-88, ASTM C326-09, ASTM C689-09, and ASTM C372-94. Phase analysis and microstructure of selected formulations were analyzed by using XRD and SEM. For the formulation having 37.7-20.7-41.6 of C-Q-F ratio and pottery stone in substitute for 100% silica, after firing at 1200 °C showed 9.27% total shrinkage, 0.17% water absorption, and 60 MPa flexure stress. The crystal structure resulted in higher amount of mullite. The linear thermal expansion and thermal expansion coefficient were lower to 0.34 and 7.07 × 10−6/°C, respectively. The difference of linear thermal expansion between the formulated body and commercial white-opaque glaze was − 0.02 at 500 °C. The shrinkage difference of body and glaze showed that the glaze-body fit was under slightly amount of compression. As a result, the formulation with the substitute for 100% silica could be vitrificated at lower temperature and indicated positive trends towards lower dunting during firing. [ABSTRACT FROM AUTHOR]

Optimization of MgTiO3–CaTiO3 based LTCC tapes to be used for microwave purposes was investigated. Three kinds of MgTiO3–CaTiO3 based powders containing B2O3 in different forms, and two different slurry systems (PVB and PM) were prepared for tape casting. The results clearly demonstrated that if the powder contained ‘free’ B2O3, no proper tape could be fabricated regardless of the slurry system. With other powders containing pre-reacted B2O3, dense tapes as well as multilayer strip line resonators could be fabricated. Difficulties to prepare proper tape from the powder containing ‘free’ B2O3 and different tape properties with different slurry systems are studied and discussed. [Copyright &y& Elsevier]