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问:如何选择、铺贴及维护保养陶瓷砖?答:1陶瓷砖的分类1)按外观分类。一般分为2大类,即釉面砖和抛光砖。2)按吸水率分类。一般分为5大类,即瓷质砖(吸水率E≤0.5%),炻瓷砖(0.5%相似文献   

陶瓷砖吸水率、背纹及砖底粉残留量对粘结性能的影响

笔者通过拉拔试验研究了陶瓷砖吸水率、砖底背纹、砖底粉残留量对陶瓷砖粘结性能的影响。结果表明:吸水率越低,对瓷砖胶粘结力性能要求就越高,细炻砖和陶质砖正常生产工艺,残留下的粉底并不会对粘结力造成影响。陶瓷砖的吸水率、背纹和砖底粉残留量这3大因素对粘结强度的影响结果:影响能力吸水率砖底粉残留量背纹。     

用磷石膏制陶瓷墙地砖的研究

以贵州矿磷石膏为原料,加入适量烧结助剂,通过模压成型和高温烧结制成陶瓷试样。结果显示,添加质量分数5%的烧结助剂,可使陶瓷试样的抗折强度由2.19 MPa增至29.23 MPa,达到了陶瓷墙地砖中细炻砖的国家标准。     

信息荟萃

2005年陶瓷砖产量突破40亿m2出口量超过4亿m2 2005年，5种陶瓷砖(瓷质砖、炻瓷砖、细炻砖、炻质砖和陶质砖)全社会产量为41．82亿m2，比上年增长23．2％。陶瓷砖出口量占产品总量的10％，陶瓷砖出口量为4．21亿m2，比上年增长32．7％；出口金额12．05亿美元，比上年增长43．5％。在2005年陶瓷砖出口中，广东佛山占出口总额的62％。佛山南海、福建福州和广东东莞分别占出口总额的6．79％、4．72％和3．09％。2005年在陶瓷砖出口国家或地区中，新加坡和香港特别行政区分别占15．59％和15．04％。从我国进口陶瓷砖占我国出口总额的7％-3％的国…     

铬渣烧制炻质砖的渣解毒机理研究

通过对铬渣－黄土－矾渣配合烧制成炻质砖的条件研究,用烧成试块的物相组成及水溶六价铬含量表征了该工艺对六价铬的最终解毒效果。     

如何克服炻质无釉劈开砖白边白面的缺陷

炻质无釉劈开砖作为一种新兴高档外墙、地面装饰材料在被市场广泛接受。该产品由于在原料及工艺上与干压施釉陶瓷砖存在很大的差别,生产过程中的缺陷种类也有显不同,其中自边白面缺陷就是典型的例子。它在干压施釉陶瓷砖生产中几乎不存在,而在炻质无釉劈开砖中普遍存在。控制不当还会造成整窑产品报废,危害性很大。     

上海陶瓷砖质监抽查两批次不合格

本刊讯6月13日,上海市质量技术监督局通报2013年市陶瓷砖产品质量监督抽查结果。通报显示,此次专项监督抽查共抽查了45批次产品,其中,2批次不合格,不合格产品为“嘉顺”炻质砖、“玉名龙”仿古砖(炻瓷砖)。     

日用炻瓷颜色釉色差产生的原因与对策

1前 言 为了适应国际市场的需求,炻瓷品种不断更新,我厂近年来除了生产白釉炻瓷外,还增加了数种颜色釉炻瓷茶具。在生产中发现因种种因素造成的产品色差问题比较严重,使企业蒙受了不应有的损失。本文仅就颜色釉生产中色差产生的原因,在釉浆性能、工艺操作、烧成制度,色剂加入量等方面作出阐述,供同行参考,指正。 2釉浆性能的影响 众所周知,釉料的细度影响着釉浆的均匀性、悬浮性和稳定性。釉料通过细磨不仅可以改善上述性能,还可以降低釉料的成熟温度,扩大色料在釉浆中的溶解度和分散度,从而使釉料发色均匀,纯正。如果釉料颗…     

上海质监通报2013年陶瓷砖产品质量监督抽查结果

上海市质量技术监督局6月13日通报2013年上海市陶瓷砖产品质量监督抽查结果,“嘉顺”炻质砖、“玉名龙”仿古砖（炻瓷砖）上不合格名单。本次抽查产品45批次,依据GB6566—2010《建筑材料放射性核素限量》、GB／T4100—2006《陶瓷砖》等国家标准及相关标准要求,对产品的下列项目进行了检验：尺寸;吸水率;断裂模数;破坏强度;无釉砖耐磨深度;抗釉裂性;耐化学腐蚀性;     

洁净钢生产用钢包内衬的改进

研究了洁净不锈钢生产用浇铸钢包内衬的改进。首先,为了改善低碳含量的MgO—C砖的抗热震性,分别对碳质材料的种类以及添加剂的含量进行了研究。研究发现,通过使用膨胀石墨、细石墨和炭黑并且减少金属添加剂的含量,可以改善材料的抗热震性。区域试验表明,将研制的低碳MgO—C砖用于渣线部位,钢中增碳量降低。此外,对于白云石碳砖防止氧化物夹杂的产生进行了研究。白云石碳砖用于钢水区域,钢中氧化物夹杂降低。     

Effect of porosity on the elastic properties of porcelainized stoneware tiles by a multi-layered model

Porcelainized stoneware represents a leading product in the world market of ceramic tiles, thanks to its relevant bending strength (with respect to other classes of tiles) and extremely low water absorption: these properties derive from its really low content of residual porosity. Nevertheless, an accurate investigation of the cross section of a porcelainized stoneware tile reveals a non-uniform distribution of the residual pores through the thickness, which results in a spatial gradient of properties. Porcelainized stoneware, therefore, may be looked at as a functionally graded material. In the present research, commercial porcelainized stonewares were analysed in order to define the effect of the residual porosity and its spatial distribution on the mechanical properties of tiles. Polished cross sections of porcelainized stoneware tiles were investigated by optical and scanning electron microscopy in order to define the content and distribution of residual pores as a function of distance from the working surface. For each porcelainized stoneware, the local elastic properties of the ceramic matrix were measured by a depth-sensing Vickers micro-indentation technique, then the so-obtained microstructural images and elastic properties were used to model the stoneware tile mechanical properties. In particular, the cross section of each tile was described as a multi-layered system, each layer of which was considered as a composite material formed by a ceramic matrix and residual pores. The elastic properties of each layer were predicted by applying analytical equations derived from the theory of composite materials and, as a new approach, by performing microstructure-based finite element simulations. In order to validate the proposed multi-layered model and identify the most reliable predictive technique, the numerical results were compared with experimental data obtained by a resonance-based method.     

Color matching algorithms in ceramic tile production

In the present work, the possibility of transferring in the ceramic tiles production the know-how developed in the field of the paints by using the Kubelka–Munk theory, in the form used for opaque surface coatings, have been evaluated. Five different target colors have been chosen as target and tried to reproduce with an industrial glaze in a cycle for fine porcelain stoneware tiles. Four industrial pigments have been chosen as basic stains for the formulations. The results show a good efficiency of the color matching algorithm applied to pigments for glazes for fine porcelain stoneware tiles. All the formulations, in fact, have allowed to obtain a value of ΔE^* lower to the accepted limit.     

Elastic properties of porous porcelain stoneware tiles

Porcelain stoneware tiles are industrially processed by using high sintering temperatures and fast firing cycles that result in products characterized by an almost impervious surface layer surrounding a rather porous bulk material. Since mechanical properties are affected by porosity, the knowledge of the material stiffness is an important parameter to define the service behavior of tiles. In the present investigation, porcelain stoneware samples having different closed porosity were investigated in order to understand the influence of the porosity on the elastic constants of the materials.Based on the quantitative XRD phase composition, elastic constants have been calculated via Voigt-Reuss-Hill averaging, and the influence of porosity has been taken into account via power-law and exponential relations. It is shown that the effective elastic constants predicted by exponential and power-law relations are in agreement with experimental values. It may be concluded that for this class of materials, in the porosity range below 14–16%, both exponential and power-law relations are helpful tools to design tiles with controlled microstructure and tailored mechanical properties.     

Utilization of granodiorite in the production of porcelain stoneware tiles

In the present study, the use of granodiorite, as fluxing agent in a body mix for stoneware ceramic tiles production, was assessed. Four batches were formulated using clay from Khaboba, and natural granodiorite from Saint Katherine, Sinai, Egypt. The batches were tailored to completely replace both feldspatic and inert components of stoneware ceramic tiles. Densification was studied according to ISO rules, while sinterability was estimated by optical dilatometry. The dependence of microstructure and mechanical properties of stoneware ceramic tiles on granodiorite content was discussed. Strength measurements showed that increasing granodiorite content the bending strength of the bodies increased. In particular the studied batches can be used for the production of industrial fast firing tiles. The obtained ceramic tiles possess properties similar to commercial ceramic floor and/or wall tiles.     

Lead Free Cu-Containing Frit for Modern Metallic Glaze

A lead-free frit containing high amount of copper and its glaze conceived for fine porcelain stoneware tiles were investigated. The glazes obtained under industrial firing were studied using X-ray photoelectron spectroscopy, X-ray diffraction, optical and scanning electron microscopy with energy dispersion spectroscopy. The mechanism of the red color formation on the surface was explained. The results indicated that the glaze presents a metallic gloss and iridescent colors on the surface, mainly associated to the formation of CuO crystallites and Cu metallic particles. Moreover, the Cu glaze showed a good chemical durability; this is particularly interesting because commercial Cu frits usually present poor chemical properties.     

Development of Low-Firing B-Fluxed Stoneware Tiles

In a global period of economic recession, innovation is a key requisite to get over this critical phase and prompt an upturn in the economy. Even the market of traditional ceramics is in a stalemate and producers desperately seek for new ideas which may supersede the long-used stoneware tiles. This paper presents the full characterization of a new potential class of ceramics named low-temperature stoneware tiles , highlighting their advantages and disadvantages. The body formulation and the firing process are both covered by an Italian Patent. This innovative product exhibits technological and esthetical features analogous to those of the traditional stoneware tile bodies but is fired at a maximum temperature of 950°C, about 250°C lower than the firing temperature of stoneware tiles. This is possible thanks to the addition of a B-rich frit to the mixture composed of quartz, feldspars, and clays. The frit acts as a low-temperature flux and promotes the melting of the feldspars. Within the fired body, the residual phases are quartz and feldspars. The newly formed phases can be β-spodumene if Li is present in the frit or spinel if Mg is present in the natural materials. The best body formulations have been characterized with mineralogical, microscopic, and technological methods. The major weakness of these ceramic bodies is their unresistance to acids. The chemical nature of the sintered matrix, with a high content of alkalies and B, triggers off the tendency of the ceramic body to react in contact with acidic solutions. Another penalty factor is the cost of the B-rich frit used in the formulation of the ceramic mixture which increases the overall cost of the ceramic body.     

Optimization of the technological properties of porcelain tile bodies containing rice straw ash using the design of experiments methodology

This study examines the effects of replacing fluxing and filler materials with rice straw ash (RSA) in manufacturing porcelain stoneware tile, using the design of experiments (DOE) methodology. The results of the characterization were used to obtain statistically significant, valid regression equations, relating the technological properties of the dried and fired test pieces to the raw materials content in the unfired mixtures. The regression models were analysed in relation to the X-ray diffraction and scanning electron microscopy results and used to determine the most appropriate combinations of traditional raw materials and RSA to produce porcelain stoneware tiles with specific technological properties. The studied range of tile body compositions: clay (40 wt%), feldspar (20–50 wt%), feldspathic sand (5–20 wt%), and RSA (0–25 wt%) was shown to be appropriate for porcelain stoneware tile manufacture.     

Influence of zeolites on the sintering and technological properties of porcelain stoneware tiles

Low-cost zeolitic rocks are promising substitutes for feldspathic fluxes in ceramic bodies, since their fusibility, modest hardness and high cation exchange capacity (CEC) should improve grinding and sintering. Five large-scale Italian deposits of natural zeolites with different mineralogy were characterised and tested in porcelain stoneware bodies. Their behaviour during processing was appraised and compared with that of zeolite-free bodies. Zeolites increased the slip viscosity during wet grinding, causing a coarser grain size distribution and consequently some drawbacks in both unfired and fired tiles. After overcoming this hindrance by dry grinding of zeolite rocks, the technological behaviour of zeolite-bearing tiles appear to be similar to that of current porcelain stoneware, though with larger firing shrinkage and residual closed porosity.     

Steel particles–porcelain stoneware composite tiles: An advanced experimental–computational approach

Innovative porcelain stoneware tiles with a surface layer containing 2.4 wt% of stainless-steel particles were produced by the Double Charge Technology. Considering this layer as a composite material, the effects of the metal particles on the mechanical behaviour of the ceramic matrix were extensively investigated in terms of Young's modulus, fracture toughness and flexural strength. With this aim, composite materials were prepared by using the same silicate-based ceramic matrix with increasing weight percentages of the same stainless-steel powder. The composites were accurately characterised. In particular, due to the high sintering temperature, possible changes at the interface between metal particles and ceramic matrix were thoroughly analysed by means of SEM and EDS microanalysis. To clarify the role of the observed chromium-rich interphase on the mechanical behaviour of the steel particles–stoneware composites, analytical equations were used and simulations were performed by using the Object Oriented Finite (OOF) element method.     

Measurement of hardness on traditional ceramics

To reveal quantitatively the hardness of clayware and stoneware, Mohs, Vickers (micro and macro) and superficial Rockwell indentation measurements were applied to roofing tiles with different porosity. This work discusses the comparison of different indentation results, indentation size effect on porous clayware and the effect of microstructure on hardness of tiles. As a result, for Vickers indentation test, the critical indent load was found to 0.5 and 1 kg for soft and hard tiles, respectively, and indentation size/load effect (ISE) appeared clearly in hard tiles. The relationship between load (P) and indent size (d) on tiles was very close to a modified Myer’s law. The PSR (proportional specimen resistance) model gave P/d=0.67+0.02d, P/d=1.33+0.1d for soft and hard tiles, respectively. It was found that there were no difference in hardness of tiles mounted with epoxy or copper and as-received sample under superficial Rockwell indentation. These concepts on the harness evaluation of tiles would be applicable to other clayware.