The development and characterisation of zinc crystal glazes used for Amakusa-like soft porcelains

The thermal and microstructural behavior of a R2O–RO–(ZnO)–Al2O3–(TiO2)–SiO2 based macro-crystalline raw glaze system

“…However, the high thermal expansion coefficient of Na 2 O causes crackles on the glaze surface. This property of Na 2 O can be eliminated by the addition of Li 2 O in the glaze recipe [2,7]. Li 2 O is a fluxing agent of raw alkaline glazes promoting stability as well as reducing the thermal expansion [1].…”

“…Its unmatured surface is related to the high levels of Al 2 O 3 and SiO 2 . Depending on the type of compositions and clay bodies, the gloss firing temperatures of crystalline glazes can vary from 1250 to 1300 1C [6,7,11,12,[17][18][19][20]. In contrast with previous studies, R 2 O-RO-(ZnO)-Al 2 O 3 -(TiO 2 )-SiO 2 system raw macro-crystal glazes were successfully developed at a relatively low maximum firing temperature of 1205 1C, promising a time consuming and cost effective production.…”

“…Moreover, the white final color and suitable chemical composition of the porcelain bodies improve the crystalline formation and final appearance [6,7]. Besides the firing schedule and substrate composition, other factors such as glaze thickness and viscosity also affect the crystallization, resultant reflectance, and color of the porcelain glazes [8].…”

“…In the literature, many studies have been conducted on nucleation and crystallization of ZnO containing crystalline glazes, but generally for fritted compositions or high firing temperatures [6,7,11,12,17,19,20]. Moreover, a comparative study of the effect of TiO 2 both as a nucleating agent and a major crystallite in macrocrystalline glazes has not been evaluated in terms of thermal behavior, viscosity, and microstructure [14][15][16].…”

Contribution of analytical techniques to determine the technologies used in the ceramic materials from the Former Workers Hospital of Maudes, Madrid (Spain)

“…Enamels are composed primarily of silica, which forms the vitreous lattice; tin oxides, which act as opacifiers; and lead oxides, which lower the melting point [13][14][15]. Due primarily to their high cost, tin oxides have been gradually replaced with other equally opacifying materials such as titanium, zirconium and zinc oxides as well as zirconium silicate [16][17][18].…”