澳洲锂辉石在陶瓷釉料中的应用

本文介绍了澳洲锂辉石的特性及其在陶瓷釉料中的作用、机理及使用方法,并对使用澳洲锂辉石所产生的经济效益进行了分析。     

R2O-RO-B2O3-SiO2-Al2O3-P2O5-CaF2分相-析晶乳浊釉的形成机理

通过正交试验方法优化釉料组成和烧成工艺，制备了R2O-RO-B2O3-SiO2-Al2O3-P2O5-CaF2多元系光亮无锆的分相-析晶乳浊釉。采用X射线衍射仪、透射电子显微镜／X射线能谱、场发射扫描电子显微镜等研究了釉的显微结构及分相与析晶的形成机理。结果表明：析晶与分相结构并存，分相促进析晶；尺寸接近可见光波长的孤立液滴和所析出的钙钠长石晶体是釉面产生乳浊的根本原因。研究了不同烧成制度对分相-析晶乳浊釉显微结构的影响，发现缓冷釉样的分相液滴尺寸明显大于急冷釉样，急冷釉样中的第二相形貌表里存在明显差异，内部呈球形液滴状，表面则为蠕虫状。     

Radioactivity Measurements on Glazed Ceramic Surfaces

A variety of commonly available household and industrial ceramic items and some specialty glass materials were assayed by alpha pulse counting and ion chamber voltage measurements for radioactivity concentrations. Identification of radionuclides in some of the items was performed by gamma spectroscopy. The samples included tableware, construction tiles and decorative tiles, figurines, and other products with a clay based composition. The concentrations of radioactivity ranged from near background to about four orders of magnitude higher. Almost every nuclide identification test demonstrated some radioactivity content from one or more of the naturally occurring radionuclide series of thorium or uranium. The glazes seemed to contribute most of the activity, although a sample of unglazed pottery greenware showed some activity. Samples of glazing paints and samples of deliberately doped glass from the World War II era were included in the test, as was a section of foam filled poster board. A glass disc with known ²³²Th radioactivity concentration was cast for use as a calibration source. The results from the two assay methods are compared, and a projection of sensitivity from larger electret ion chamber devices is presented.     

Synthesis of Gray Zirconium Silicate Pigments from Zircon Mineral

Zirconium silicate (zircon) pigments in new gray hues have been prepared from mineral zircon as a low-cost raw material. In the first step this material was deocmposed with a waste mixture of NaOH-KOH. In the second step the pigments were synthesized with addition of manganese, especially manganese(II) carbonate, as the chromophore. The optimum conditions for the syntheses of pigments have been estimated and the properties of products (hues, applicability to ceramic glazes) have been evaluated.     

明代早期祭红釉显微结构与工艺的研究

收集了明代早期 (永乐、宣德、成化 )不同年代的祭红釉瓷残片。用扫描电镜、透射电镜、能谱仪、电子衍射、荧光X射线光谱分析、光学显微镜等系统地研究了它们的显微结构 ,用体视显微镜、分光光度计等观察、测定了它们的呈色状况 ,详细探讨了明代祭红釉之间的差别 ,分析了它们的生产工艺与化学组成、显微结构之间的关系。     

Kinetic Model for Crystallization in White Ceramic Glazes

Theoretical equations have been developed for crystal growth rate in layers of small frit (glass) particles during firing. Throughout the process, the crystalline and the glassy phases have different compositions; therefore, the system can be considered a pseudo-two-component system consisting of a crystallizable component (structural unit) and a noncrystallizable mixture of several components. The concentration of the crystallizable component decreases in the residual glassy phase during the crystal growth process, on integrating at the surfaces of crystals having the same composition. Throughout the crystal growth process, a concentration gradient of the crystallizable component is therefore produced in the glassy phase, which results in mass transport by diffusion of this component from the bulk residual glassy phase to the surfaces of the crystals. Equations have been derived assuming that the diffusion step of the crystallizable component through the residual glassy phase is the overall crystal growth process rate-controlling step.     

Effect of ZnO/MgO ratio on the crystallization and optical properties of spinel opaque glazes

The effect of the ZnO/MgO ratio on the crystallization and optical properties of glass‐ceramic glazes from the SiO₂–Al₂O₃–ZnO–MgO–CaO–K₂O–Na₂O–B₂O₃ system was studied. The glazes with different ZnO/MgO ratios were characterized by differential scanning calorimetry, X‐ray powder diffraction, Raman spectroscopy, scanning electron microscopy, energy dispersive spectroscopy analysis and a spectrophotometer. The results reveal that the A glaze without ZnO content contains forsterite and sapphirine. The B and C glazes with intermediate ZnO/MgO ratio contain enstatite and spinel solid solution. The D to F glazes with higher ZnO/MgO ratio crystallize spinel solid solution as the only crystalline phase. The amount of spinel solid solution, lightness values (L*), gloss values and the reflectance of the studied glazes increase with the ZnO/MgO ratio.     

The production of a lead glaze with galena: Thermal transformations in the PbS–SiO2 system

Galena, also known as PbS, was widely used in the production of lead glazes from the beginning of the 18th century to the second half of the 20th century. Although the PbO‐SiO₂ system has been studied for years, the PbS–SiO₂ phase diagram, involved in the formation of a glaze with galena, has not yet been investigated. Temperature transformations for the system 75 wt% PbS‐25 wt% SiO₂ are investigated in a high‐temperature resolved X‐ray diffraction experiment with synchrotron radiation and compared to those of the equivalent system 70 wt% PbO‐30 wt% SiO₂. Lanarkite, PbO·PbSO₄, is the phase predominantly formed as soon as galena decomposes during the heating. The results show that the system melts at a temperature higher than the PbO–SiO₂ system, but far lower than those expected for the PbO–PbSO₄–PbS system. A historical misfired lead glaze produced with galena is also studied. The presence of galena, lanarkite, and mattheddleite, Pb₁₀(SiO₄)_3.5(SO₄)₂Cl_2, is determined and discussed in terms of the composition of the galena mineral used and the firing conditions in light of the high‐temperature transformations previously obtained.     

Development of anorthite based white porcelain glaze without ZrSiO4 content

The aim of this study was to develop new compositions of white glazes without the addition of ZrSiO₄designed for sanitary products obtained in a 12-h firing cycles at a maximum temperature of 1230 °C.Alternative glazes with a good opacity and a high degree of whiteness were obtained, composed primarily of raw materials available on the domestic market in Poland. The opaque effect was achieved due to crystallisation of anorthite, which was identified as a major crystalline phase in the system. The glazes were characterised by a high whiteness value L*, greater than 90 in the CIELAB colour space, and a gloss, measured with a 60° light incident angle on the glaze surface, above 50%.The microstructure and structure of the glazes were measured with the use of a Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). The colour and gloss of glazes were measured with the use of a spectrophotometer and a gloss metre at a 60° angle of incidence. The topography of glazes surfaces, as well as the roughness level (Ra), were measured with the use of a confocal microscope.     

我国色釉料产业现状及发展趋势分析

从我国色釉料行业的现状、发展趋势、仿古砖色料、全抛釉技术、喷墨打印技术、原料标准化以及加强基础研究和技术创新等角度进行了分析评述。