Study On Split Phase Opacified Glaze

Due to use of opacified glaze with good covering power, large number of poor mineral materials and industrial wastes were widely used in ceramic body, which advantage to improve the ecological condition and reduce cost of production. Opacified glaze is widely used not only in architecture and sanitary ceramics, but in ?omestic ceramics as well. Opacified glaze could be classified 3 kinds according to its formatting mechanics which were gas phase opacified glaze, solid phase opacified glaze and split phase one.A split phase opacified glaze is researched in this thesis. The opacified glaze is prepared which fired at 1250-1270? using orthogonal test as method, and feldspar, quartz, clay, talc, lime carbonate, zinc oxide, synthesized calcium phosphate, fluorite, zirconium silicate as materials. It was researched that effect of composition and processing factors on properties of glaze, as well as opacifying mechanics. Samples were characterized by means of XRD, SEM, TEM, TG-DTA, XRF,thermal dilatometer, microhardness tester and colorimeter.Result showed that in this system the optimum composition of the glaze was: 39%feldspar,25%quartz,4%clay,6%talc,4%lime carbonate,5%zinc oxide, 4%synthesized calcium phosphate,3%fluorite,10% zirconium silicate. Whiteness of the glaze increased with the increase of firing temperature. Glazes' whiteness and lustrousness were 83.6,103, respectively. Properties of the glaze would be increased with properly soaking time both at oxidating period and high temperature stage.Forming mechanics of the glaze was due to large number split phase particles in glaze known with phase and structure analysis, particles with size about 0.1?0.2?m distributed in glaze homogeneously. A large number of zirconium silicates'particles existenced in glaze with size about 1?m was another important factor contribution to glazes' opacification.Thickness of glaze is about 0.5mm, interlayer of body and glaze is not obvious. Thermal expansion coefficients of the body and glaze burnt at 1270? were 7.5×10-6/?,6.3×10-6/?, respectively, Body-glaze fit pretty well. Microhardness of the glaze is 848.9 kg/mm2.