TiO2对（K,Na）2O–CaO–Al2O3–SiO2–B2O3系分相乳浊釉性能及结构的影响

Effect of Titanium Dioxide on Properties and Structure of Phase-separated Opaque Glaze in （K,Na）2O–CaO–Al2O3–SiO2–B2O3 System

用扫描电子显微镜、透射电子显微镜、红外光谱、光电子能谱、色度仪等测试手段研究TiO2对（K,Na）2O–CaO–Al2O3–SiO2–B2O3系1 200℃低温快烧分相乳浊釉的釉面光学性能及结构的影响。结果表明：随着TiO2引入量的增加,釉面白度及光泽度获得显著提高,白度由44.1%增至82.1%,光泽度由34%增至79%,白度越高,釉乳浊性能越好。但当TiO2引入为6%（质量分数）时,釉面向黄色调偏移。Ti在分相釉玻璃体中主要以Ti4＋存在;TiO2有利于釉玻璃网络结构的转变,提高釉的分相倾向,使分相液滴尺寸及组成产生显著变化,强化了釉层对入射光的散射能力,致使釉面乳浊性能明显提高。烧成过程中釉乳浊性能的形成主要源于烧成过程中釉玻璃体的冷却阶段,尤其是低温阶段（T≤900℃）分相液滴尺寸及组成的变化。

The effect of titanium dioxide （TiO2） on the optical properties and the structure of （K,Na）20-CaO-Al2O3-SiO2-B2O3 system low-temperature （1 200 ℃） fast-fired phase-separated opaque glaze was investigated. The glaze samples were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and colorimetry, respectively. The results show that the whiteness and the glossiness of the glazes improve when the TiO2 content increases, i.e., the whiteness increases from 44.1% to 82.1% and the glossiness increases from 34% to 79%. The higher the whiteness is, the higher the opacifying performance of the glaze will be. However, the color of glaze surface becomes yellow when the TiO2 content is up to 6% （in mass fraction）. This is since Ti4＋ is the main status of Ti in the glaze. The addition of TiO2 contributes to the improvement of the phase-separation via changing the glazed network structures. The change of the size and composition of phase-separated drop increases the scatter light ability of the glazed layer, thus leading to the improvement in the opacification of the glaze. The opaque performance of the opaque glaze is mainly formed due to the transformation of phase-separated size and composition during the cooling process of sintering, especially at low temperatures （i.e., ≤900℃）.