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Gulsu Simsek - One of the best experts on this subject based on the ideXlab platform.
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on site identification of early bottger red Stoneware using portable xrf raman instruments 2 glaze gilding analysis
Journal of the American Ceramic Society, 2015Co-Authors: Gulsu Simsek, Philippe Colomba, Francesca Casadio, Ludovic Ellotgurle, Ghenete Zelleke, K T Fabe, Veronique Milande, Laurence TilliardAbstract:Twenty-one glazed red Stoneware objects, with gilded or gold-painted decor from different collections (Cite de la Ceramique, Sevres, France; Art Institute of Chicago, USA; a private collection) attributed to 18th century Bottger, Meissen (Saxony) have been analyzed with a portable X-ray fluorescence spectrometer (XRF) and portable or fixed Raman micro-spectrometer in laboratory/museum/collector rooms. Analysis was aimed at gaining a deeper understanding of the technology of production of the gilding and black glaze, to augment what is known from the limited literature. Three different techniques to obtain a golden decor emerged as a result of this study: (i) a true gilding with gold, (ii) gold with mercury, and (iii) an alloy of copper and zinc.
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on site identification of early bottger red Stoneware made at meissen using portable xrf 1 body analysis
Journal of the American Ceramic Society, 2014Co-Authors: Gulsu Simsek, Philippe Colomba, Francesca Casadio, Ludovic Ellotgurle, Ghenete Zelleke, K T Fabe, Veronique Milande, Eric MoineAbstract:A selection of 50 red Stoneware objects, polished, unpolished, partially polished or glazed, from different collections (Departement du Patrimoine et des Collections de la Cite de la Ceramique, Sevres, France; Art Institute of Chicago; a private collection), attributed to 18th century Bottger, 20th century Meissen (Saxony) and Chinese productions have been analyzed with a portable X-ray fluorescence spectrometer in museum/collector rooms. The comparison of major (Si, Al), minor (K,Ca,Fe), and trace (Ti, Mn, Zr, Rb, Sr) element ratios was made to assist with the classification of the different artifacts as a function of their production technology and raw materials. The results are discussed in light of historical reports on the characteristics of Bottger production and criteria of identification are proposed to distinguish between “classical” Bottger (early 18th century) and other productions.
L Esposito - One of the best experts on this subject based on the ideXlab platform.
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sintered esseneite wollastonite plagioclase glass ceramics from vitrified waste
Journal of The European Ceramic Society, 2009Co-Authors: Enrico Bernardo, E Rambaldi, Yiannis Pontikes, L Esposito, A Tucci, G N AngelopoulosAbstract:Abstract Dense sintered esseneite–wollastonite–plagioclase glass–ceramics have been successfully prepared from a vitrified mixture of important inorganic waste (Bayer process red mud, fly ash from lignite combustion and residues from the polishing of porcelain Stoneware tiles). The enhanced nucleation activity of fine glass powders, favoured by particular oxidation conditions, caused a substantial crystallisation, even in the case of very rapid thermal treatments at 900 °C, which led to remarkable mechanical properties (bending strength and Vickers micro-hardness exceeding 130 MPa and 7 GPa, respectively) and a promising chemical durability.
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using waste glass as a partial flux substitution and pyroplastic deformation of a porcelain Stoneware tile body
Ceramics International, 2007Co-Authors: E Rambaldi, A Tucci, W M Carty, L EspositoAbstract:The glass phase composition of fired porcelain Stoneware samples was used as a benchmark for the incorporation of waste glass into whiteware bodies. Starting from a commercial standard porcelain Stoneware body mix, a new mix was prepared by partially replacing feldspathic sands with scrap soda-lime glass and additional clay, to keep the overall chemical composition, and therefore the glassy phase composition constant. The resulting bodies have similar characteristics and properties. The glassy phase compositions of the two bodies are similar and moreover do not vary significantly from the glassy phase compositions of commercial whiteware bodies studied in previous work. Pyroplastic deformation was also measured and the body containing recycled glass had significantly lower deformation compared to the standard body. This difference was attributed to poor mixing in the standard body, as is supported by the quartz particle separation distance distribution in the fired microstructure.
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use of scrap glass as raw material for porcelain Stoneware tiles
Advances in Applied Ceramics, 2006Co-Authors: A Tucci, E Rambaldi, L EspositoAbstract:AbstractThe possibility of recycling scrap glass (soda lime, lead and barium based glasses) by incorporation into a porcelain Stoneware tile mix has been examined. Starting from a standard porcelain Stoneware body mix, several modified mixes were prepared by replacing different amounts of the fluxing component, a sodium feldspathic sand, with three types of scrap glass: a soda lime glass from urban wastes, a lead based glass from the neck part of cathode ray tubes (CRTs), and a barium based glass from CRT panels. The replacement of feldspar sand with a soda lime scrap glass, in the range 5–10 wt-%, allows porcelain Stoneware materials to be obtained with good characteristics. A slight decrease in the water absorption of the fired material is observed after sintering at the same temperature as the reference mix. Furthermore, flexural strength remains high and the microstructural homogeneity enhances reliability. The presence of 2 and 5 wt-%, of lead and barium based scrap glass respectively, both character...
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use of scrap soda lime silica glass in traditional ceramics
Glass Technology, 2005Co-Authors: Yiannis Pontikes, G N Angelopoulos, Angeliki Christogerou, E Rambaldi, L Esposito, Arianna TucciAbstract:A Iternatives ways of recycling soda-lime-silica scrap glass (SLS) glass, apart from remelting can offer certain advantages and may be implemented when glass production is not suitable. For the ceramics industry, the incorporation of glass into the ceramic body may improve the quality of fired products and save energy. Mixtures of SLS glass and ceramic raw materials used for the production of porcelain Stoneware tiles and heavy-clay products were developed and examined. In the case of porcelain Stoneware tiles, several modified mixes were prepared by replacing different amounts of the fluxing component, sodium feldspathic sand. For roofing tiles, SLS glass was added at a fixed percentage in the body mixes. The fired samples were characterised in terms of linear shrinkage, water absorption, flexural strength and reliabilit Microstructure and the main phase transformations in the fired samples were examined by x-ray diffraction and by scanning electron microscopy along with EDS microanalysis. The results, for the porcelain Stoneware body mix, show that a substitution of the fluxing component in the range of 5-10 wt% is feasible. The new formulations had lower water absorptions, adequate flexural strengths and a consistent increase in reliability due to improved homogeneity. For substitutions exceeding 10 wt%, plagioclase was crystallised, which inhibited the formation of mullite and did not favour densification. The results regarding the modified body mix for heavy clay products have shown that a glass additions up to 30 wt% are feasible. New crystalline phases were developed within and at the interface of the glass grains. The particle size distribution of the glass and the firing temperature both influenced the physical and mechanical characteristics whereas they had a minor effect on the mineralogy. The fired products demonstrated improved characteristics in terms of water absorption and bending strength.
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microstructural variation in porcelain Stoneware as a function of flux system
Journal of the American Ceramic Society, 2005Co-Authors: G P Souza, L Esposito, A Tucci, Elisa Rambaldi, W E LeeAbstract:Fired microstructures of standard porcelain Stoneware tile and tile made from mixes containing waste glass as part of the flux system were studied by XRD, SEM, and TEM. The standard porcelain Stoneware microstructure consists of 100-1000 μm long mullite needles, feldspar relics, and partially dissolved α-quartz embedded in a glassy matrix. The use of soda-lime-silica (SLS) glass in the flux system led to crystallization of plagioclase, wollastonite, and sodium silicates. CaO-rich areas adjacent to quartz particles, as a result of interactions between SLS glass and silica from the quartz, and eutectic morphologies, revealed that SLS glass accelerated liquid formation and thus sintering and densification. Formation of these additional phases led to lower levels of quartz, mullite, and Na-feldspar in the microstructure although lower firing temperatures could be used to achieve full density due to generation of more fluid liquid. Use of PbO-containing waste glasses had little effect on the microstructure compared with standard composition while use of mixed PbO-containing and SLS glasses led to microstructures containing plagioclase but to lower extent than in tile with higher levels of SLS.
F J P Sousa - One of the best experts on this subject based on the ideXlab platform.
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distribution of contact pressure over the surface of ceramic floor tiles during the polishing process
Journal of The European Ceramic Society, 2014Co-Authors: Ahryman Seixas Busse De Siqueira Nascimento, F J P SousaAbstract:Abstract Assisted with computational simulation this work quantitatively determined the distribution of contact pressure over the surface of porcelain Stoneware tiles during the industrial polishing process. In modern polishing lines there are basically three movements responsible for the scratching velocity and the position of the abrasives. Combining the kinematic equations obtained by these movements with a pre-existing model the contact pressure between abrasive tool and tile surface could be determined as function of time. The spatial distribution of average, standard deviation and maximum values of contact pressure were then obtained and mapped over the entire surface. The simulation results showed that the contact pressure tends to be 50% higher near to the center, in regions worked by the innermost abrasives. Additionally, periodical variations of up to 10% were found to occur due to the partial retreat of the abrasive tool.
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glossiness distribution over the surface of Stoneware floor tiles due to the polishing process
Journal of Materials Science, 2007Co-Authors: F J P Sousa, Walter Lindolfo Weingaertner, Nerio Vicente, Orestes Estevam AlarconAbstract:The industrial process for polishing floor tiles requires several polishing stages in order to produce the desirable glossiness. Works on floor tile polishing with focus on the distribution of glossiness still lack in literature. The present work intends to measure and analyze the distribution of glossiness over the surface of porcelain Stoneware tiles polished using forward speed of 7.5 cm s−1 and lateral oscillation frequency and amplitude of 0.2 s−1 and 12 cm. The glossiness pattern generated by the polishing process over the surface of six tiles were presented in grey-scale graphics, where each pixel was univocally associated with a portion of the tile surface. Correlations between the glossiness pattern found and the polishing kinematics were developed. Significant differences of glossiness were registered either between tiles polished under the same polishing condition, or within the surface of the same tile, between adjacent regions. The use of lateral oscillation motion caused the glossiness pattern over the tile surface to follow a waveform pattern, and two corroborative hypotheses were made in order to explain such fact, considering the light-surface interaction as well as the overlapping of trajectories of adjacent polishing heads.
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kinematics of a single abrasive particle during the industrial polishing process of porcelain Stoneware tiles
Journal of The European Ceramic Society, 2007Co-Authors: F J P Sousa, Jan C Aurich, Walter Lindolfo Weingaertner, Orestes Estevam AlarconAbstract:In order to achieve glossiness the porcelain Stoneware tiles must undergo an industrial polishing process, which can be optimized by either the scratching phenomena or the polishing kinematics. This paper is focused on the latter. Thus, the most important kinematic equations involved in polishing process were described. The lateral oscillation used in modern polishing machines, as well as the other available motions were taken into account. The trajectory of abrasives, the scratching speed and the curvature radius could be obtained for each instant. The importance of adopting good kinematics parameters for the accomplishment of the polishing process was highlighted, and the equations furnished hereby serve as useful tools for further attempts in optimizing the polishing process.
Jianming Zheng - One of the best experts on this subject based on the ideXlab platform.
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the earliest chinese proto porcelain excavated from kiln sites an elemental analysis
PLOS ONE, 2015Co-Authors: Bin Zhang, Huansheng Cheng, Jianming ZhengAbstract:In June 2012, the Piaoshan kiln site was excavated in Huzhou, Zhejiang Province, which hitherto proved to be the earliest known Chinese proto-porcelain kiln. Judging from the decorative patterns of unearthed impressed Stoneware and proto-porcelain sherds, the site was determined to date to the late Xia (c. 2070–c. 1600 BC), the first dynasty of China. Here, we report on proton-induced X-ray emission analyses of 118 proto-porcelain and 35 impressed Stoneware sherds from Piaoshan and five subsequent kiln sites in the vicinity. Using principal components analysis on the major chemical compositions, we reveal the relationships between impressed Stoneware and proto-porcelain samples from the six kiln sites. The sherds from different sites have distinctive chemical profiles. The results indicate that the raw materials were procured locally. We find a developmental tendency for early glazes towards mature calcium-based glaze. It is most likely that woody plant ashes with increased calcia-potash ratios were applied to the formula.
Orestes Estevam Alarcon - One of the best experts on this subject based on the ideXlab platform.
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glossiness distribution over the surface of Stoneware floor tiles due to the polishing process
Journal of Materials Science, 2007Co-Authors: F J P Sousa, Walter Lindolfo Weingaertner, Nerio Vicente, Orestes Estevam AlarconAbstract:The industrial process for polishing floor tiles requires several polishing stages in order to produce the desirable glossiness. Works on floor tile polishing with focus on the distribution of glossiness still lack in literature. The present work intends to measure and analyze the distribution of glossiness over the surface of porcelain Stoneware tiles polished using forward speed of 7.5 cm s−1 and lateral oscillation frequency and amplitude of 0.2 s−1 and 12 cm. The glossiness pattern generated by the polishing process over the surface of six tiles were presented in grey-scale graphics, where each pixel was univocally associated with a portion of the tile surface. Correlations between the glossiness pattern found and the polishing kinematics were developed. Significant differences of glossiness were registered either between tiles polished under the same polishing condition, or within the surface of the same tile, between adjacent regions. The use of lateral oscillation motion caused the glossiness pattern over the tile surface to follow a waveform pattern, and two corroborative hypotheses were made in order to explain such fact, considering the light-surface interaction as well as the overlapping of trajectories of adjacent polishing heads.
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kinematics of a single abrasive particle during the industrial polishing process of porcelain Stoneware tiles
Journal of The European Ceramic Society, 2007Co-Authors: F J P Sousa, Jan C Aurich, Walter Lindolfo Weingaertner, Orestes Estevam AlarconAbstract:In order to achieve glossiness the porcelain Stoneware tiles must undergo an industrial polishing process, which can be optimized by either the scratching phenomena or the polishing kinematics. This paper is focused on the latter. Thus, the most important kinematic equations involved in polishing process were described. The lateral oscillation used in modern polishing machines, as well as the other available motions were taken into account. The trajectory of abrasives, the scratching speed and the curvature radius could be obtained for each instant. The importance of adopting good kinematics parameters for the accomplishment of the polishing process was highlighted, and the equations furnished hereby serve as useful tools for further attempts in optimizing the polishing process.