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.     

硅灰石在日用陶瓷釉料中的应用

叙述了釉用原料选择和硅灰石的性能，提出了含硅灰石釉料的最佳配方组成和制作工艺．并对应用中有关的几个问题进行了讨论．     

Development of anorthite based white porcelain stoneware tile compositions

The scope of the present study is to develop alternative white porcelain stoneware tile compositions without using zircon (ZrSiO₄) which have shown better whiteness values than standard white porcelain stoneware tile composition containing zircon. These new compositions are designed to develop anorthite crystals in the microstructure. Technological properties of compositions such as water absorption (%), firing shrinkage (%) and colour (L^⁎, a^⁎, b^⁎) were measured and compared with standard white porcelain stoneware tile. Scanning electron microscopy (SEM), X-ray diffraction (XRD) analyses were also carried out. One of the new anorthite-based compositions was manufactured as white porcelain stoneware tile substitute of standard white porcelain stoneware containing zircon.     

浅谈骨质瓷用无铅釉

长期以来,骨质瓷生产采用“高温素烧,低温釉烧”的二次烧成工艺。由于釉烧温度低,骨质瓷生产厂家多使用含铅釉进行装饰。含铅釉具有良好的高温流动性、高的光泽度和平滑度、较宽的烧成范围、良好的坯釉适应性等优点,而且铅釉产品色彩丰富、艳丽。但是,含铅釉料的采用给骨质瓷产     

瓷质砖坯釉料的研制

我厂内墙砖生产为二次烧成 ,为适应市场需求的变化 ,决定将其中 2条窑改为生产瓷质砖。对此 ,我们提出以下设计方案 :1)根据我厂窑炉最高烧成温度 12 0 0℃ ,设计瓷质砖烧成温度在 1180℃以下 ;2 )要求瓷质砖吸水率 <0 .5 % ,产品烧成收缩 <8% ;3)充分考虑现有陶质砖用原料 ,减少原料种类 ,以便于管理 ;4 )在釉料方面 ,为适应当今国内外市场的需求 ,考虑作防滑地砖 ,要求釉面防滑系数达到英标ＢＳ6 76 7系数的 4 0以上。根据以上要求 ,我们通过优化原料 ,研制出适宜低温快烧的坯釉料配方 ,并于 2 0 0 0年 6月试生产 ,产品各项性能指标均符合…     

颜色釉人物瓷画的表现形式

在陶瓷艺术作品中，以鲜明的性格特点和传神写照为特色的任务瓷画，在塑造人物形象揭示人物内心世界的创作过程中，以新的表现手法，融汇现代审美观念。     

Improving the flexural strength of porcelain by residual stress in anorthite coating

Flexural strength is an important parameter of domestic ceramics to meet the criteria for mechanized washing, filling, and sealing process in the automatic production line. In this work, the anorthite coating was prepared using calcite, silica, and alumina as raw materials. Taking the temperature with the highest matrix strength as the optimal temperature, the influences of chemical formulation on the phase composition and the coefficient of thermal expansion (CTE) of coatings were investigated. The enhancement effect of the coating with different formulations and surface number and thickness was compared. As a result, the flexural strength of the ordinary domestic ceramic body was improved due to the residual compressive stress in the coating caused by a mismatch of CTE between the coating and the matrix. At the optimal sintering temperature (1280°C), the coating with 20 mass% alumina addition has the best strengthening effect on the body, in which the thickness of the anorthite coating is approximately 50 µm and the flexural strength has increased by 64.6%, from 88 ± 4 to 144 ± 6 MPa.     

Influence of bone ash on the properties of porcelain glaze

It is shown that bone ash, when used instead of pegmatite, affects the properties of glazes. The addition of as much as 6% bone ash is found to enhance the whiteness of glazes by 2.7%, and to improve their gloss and thermal stability. Translated from Steklo i Keramika, No. 7, pp. 20–21, July, 1997.     

镁质强化瓷装饰用无铅镉溶出大红釉的研究

本文研制了一种适用于镁质强化瓷装饰用大红釉,大红釉以包裹型镉硒为色料,基釉为长石-石灰混合生料釉,氧化气氛烧成,烧成温度为1150~1270℃。结果表明,釉料完全无铅无镉溶出。并研究了基釉的组成、升温速率、停留时间和燃烧气氛对呈色效果的影响。最终获得了制备镁质强化瓷装饰用无铅无镉溶出大红釉制备技术。     

Anorthite-based transparent glass-ceramic glaze for ceramic tiles: Preparation and crystallization mechanism

A series of high hardness anorthite-based transparent glass-ceramic glaze was successfully developed for ceramic tiles. These glazes were prepared by mixing a high-calcium frit (denoted as HCa) that can crystallize anorthite with other fluxes. The effect of HCa content on the crystalline phase, microstructure and properties of the glaze was studied. In addition, the phase transformation, microstructure evolution and crystallization kinetics of anorthite from frit glaze were investigated in detail. The results revealed that when the HCa content was 45–55 wt%, the glazes had excellent transparency with a hardness of 6.4–7.3 GPa, which was higher than conventional glazes. The XRD and SEM tests showed the crystallization of single-phase lamellar-shaped anorthite crystals up to 20–40 μm in length. Anorthite was found to crystallize directly from the frit glaze at 850 °C. The laminated anorthite was composed of thinner lamellae, and cracks were observed inside the large crystals. The activation energy of anorthite crystallization was about 420 kJ/mol, and the Avrami index (n) was 2.03?2.36. The n value indicates that the crystal is grown in two dimensions, which explains the formation of lamellar-shaped anorthite in SEM.     

Effect of zirconia addition amount in glaze on mechanical properties of porcelain slabs

Applying toughened glaze layer on porcelain slabs can improve the fracture toughness of slabs and greatly reduce the production cost. In this study, porcelain slabs glaze with high toughness was fabricated by the processes of impregnation glazing and single firing method, using opaque frits, kaolin clay as the main raw materials, zirconia as an additive, and the effect of the addition amount of zirconia in glaze on fracture toughness of porcelain slabs was investigated. The results showed that the type and content of crystal phase of the glaze were greatly influenced by the addition amount of zirconia. Meanwhile, compared with the base glaze, the hardness and fracture toughness of the sample with zirconia glaze were significantly improved. Porcelain slabs with 10 wt% zirconia in glaze, sintering at 1200 °C, exhibited higher quality glaze and outstanding properties, including a water absorption of 1.95%, a Vickers hardness of 6.36 GPa, and a fracture toughness of 2.71 MPa m^1/2. The toughening mechanism of the glaze layer was as follows: a large number of zirconium silicate grains with high hardness were generated by the reaction of added zirconia with silica in the glass phase, which increased the content of crystal phase and then prevented the propagation of cracks; moreover during the martensitic transformation of the tetragonal zirconia grains, the volume and shear strain were generated to offset the stress field generated by the crack tip, thus toughening the material.     

低温透明无铅釉在高档日用瓷中的应用

随着人们健康和环保意识的增强,加之欧美对于陶瓷制品铅镉溶出限制标准的提高,高档日用陶瓷使用含铅的釉已不能满足出口要求,使用无铅釉装饰是必然趋势。本文简单介绍了低温烧成透明无铅釉在高档日用瓷上的应用。