Preparation of a CaCO3-TiO2 composite based opaque glaze: Insight into the mechanism of opacification and glaze yellowing inhibition. Issue 15 (December 2020)

• Record Type: Journal Article
• Authors: Sun, Sijia; Ding, Hao; Ao, Weihua; Liu, Yangai; Chang, Liang; Zhang, Jianmeng
• Is Part Of: Journal of the European Ceramic Society. Volume 40:Issue 15(2020)
• Page Start: 6171
• Page End: 6180
• Publication Date: 2020-12
• Subjects: TiO2 -- CaCO3 -- Opaque glaze -- Sanitary ceramic; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2020.07.063
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: TiO2 is a potential alternative opacifier to ZrSiO4, but it is restricted because it easily causes glaze yellowing due to the formation of rutile. Herein, the CaCO3 -TiO2 composite with close interface combination was added into the raw glaze for sanitary ceramics to prepare white glaze with negligible radioactivity. The glaze added CaCO3 -TiO2 exhibits the surface properties similar to the glaze added ZrSiO4 and its excellent opacifying effect with L* value of 89–94 is achieved by the crystallization of titanite. Moreover, the optimal glaze added CaCO3 -TiO2 shows a white surface with b* value of 2.73, while the glaze added pure TiO2 shows a yellowish surface with b* value of 7−10. Mechanism analysis indicates that the tight interface combination between CaCO3 (CaO) and TiO2 can promote their combination reaction to form perovskite and further promote the formation of titanite. Therefore, the formation of rutile is inhibited, resulting in the white glaze surface.