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During ceramic shaping, trapped oxygen increases porosity and reacts with elements to form unwanted compounds, enlarging pores. Excess phosphorus forms lumps, enhancing porosity and reducing density, leading to defects like increased brittleness, strength reduction, and improper densification, necessitating higher sintering temperatures. This study introduces extrusion-based 3D printing of a hybrid porcelain ceramic mixture with calcium silicide to achieve dephosphorization and deoxygenation while maintaining controlled sintering temperatures. Results show phosphorus is effectively removed at 1100°C and above sintering temperatures, while oxygen-related defects are reduced. Although calcium silicide does not lower the sintering temperature, it significantly improves porcelain purity, contributing to better material properties. These findings pave the way for enhanced additive manufacturing techniques in ceramic production. [ABSTRACT FROM AUTHOR]

In this study, we investigated the ozone inactivation efficiency of Bacillus atrophaeus spores attached to various tile surfaces. Eight different types of tiles were employed, considering factors such as porosity (ceramic, porcelain), color (white, black), and glossiness (matte, glossy). Inactivation was performed by exposing the spore-loaded tiles to ozone gas for a specified duration. The inactivation efficiencies of ozone gas on different tile surfaces were compared by analyzing the colony-forming units of desorbed Bacillus atrophaeus cultured in a growth medium. Results revealed a reduction in colony counts with increasing ozone exposure time, indicating a proportional enhancement in inactivation effectiveness on ozone exposure time. After exposure to ozone gas for 30 min or longer, more than 90% of spores on each tile were inactivated. Regarding porosity, ceramic tiles exhibited slightly superior inactivation effects compared to porcelain tiles. Additionally, in terms of glossiness, glossy tiles demonstrated better inactivation effects than matte tiles. However, no significant differences were observed in inactivation effects based on the color of the tiles. [ABSTRACT FROM AUTHOR]

This study aims to compare the roughness between the central and edge points on the porcelain sectional surface of porcelain fused to Co-Cr alloy endocrowns. Utilizing anatomical data from average molar dimensions, a simplified model for the endocrowns was created. Eight porcelain fused to Co-Cr alloy endocrowns were fabricated with an edge thickness of 0.3 mm. Following casting, firing, cutting, and polishing procedures, the roughness on porcelain sectional surface at both the central and edge points of the inner crown was assessed using an atomic force microscope (AFM). The roughness measurement (Sq value) for the central point on porcelain sectional surface was (10.46 ± 3.37 nm), and for the edge point, it was (10.50 ± 1.99 nm). There was no statistically significant distinction between the central and edge points in terms of roughness. Despite the uneven thickness of the inner crown in porcelain fused to Co-Cr alloy endocrowns, it was observed that this disparity had negligible impact on the internal microstructure of the porcelain. Therefore, its application in dental clinical settings could be deemed viable. [ABSTRACT FROM AUTHOR]

Porous ceramics were synthesized using porcelain tile polishing residue (PTPR) and slaked lime (Ca(OH)2) as a reinforcing agent through a hydrothermal autoclaving method. The process parameters, including the quantity of slaked lime added, the hydrothermal autoclaving temperature, and the reaction duration, were optimized meticulously. The composition, structure, thermal and physical properties of the samples were thoroughly analyzed via Brunauer–Emmett–Teller (BET) measurements, powder X-ray diffraction (PXRD), and scanning electron microscopy (SEM). The results indicated that the incorporation of slaked lime and hydrothermal autoclaving led to the formation of calcium silicate hydrate, which corresponded with an enhancement in the strength of the sample. Notably, when the quantity of slaked lime added was optimized at 30 wt%, the formation of tobermorite (5CaO·6SiO2·5H2O) was detected. At a hydrothermal autoclaving temperature of 150 °C, the formation of only sheet-like calcium silicate hydrate was observed. In contrast, at an elevated temperature of 180 °C and 210 °C, needle-like tobermorite was successfully synthesized. The porous ceramic with the most favorable structure was obtained through autoclaving at 180 °C for 10 h with 30 wt% slaked lime, exhibiting a total pore volume of 0.11 mL/g, a specific surface area of 26.35 m2/g, and a mesoporous volume fraction of 90.40%. [ABSTRACT FROM AUTHOR]

Composite materials have garnered considerable interest in the thermal industry on account of their remarkable mechanical properties and thermal resistance. The objective of this research work is to analyse the impacts of integrating porcelain infill particles into basalt fibre-reinforced polymer (BFRP) composites. Particularly, the study aims to evaluate the consequential modifications in critical thermal and mechanical characteristics. The results of mechanical testing indicate that the incorporation of porcelain fillings significantly influences the composite tensile strength, flexural strength, and impact resistance. Additionally, by employing scanning electron microscopy (SEM), significant knowledge is acquired regarding the interfacial bonding mechanisms and microstructural properties of the filler particles, polymer matrix, and basalt fibres. Utilizing dynamic mechanical analysis (DMA), the maximal values of storage modulus (3429 MPa), loss modulus (489 MPa), and damping factor (0.17) are investigated in relation to the dynamic mechanical properties across a range of temperature conditions. The research additionally illustrates enhancements in thermal characteristics, including heat deflection temperature, thermal conductivity, and coefficient of linear thermal expansion, all of which are improved by 37% when porcelain infill is incorporated into the composite. In addition, thermal gravimetric analysis (TGA) examines the degradation and thermal stability properties of the composites over an extensive temperature spectrum, reaching a maximum of 390 °C. The insights derived from this analysis are particularly pertinent to applications involving thermal insulation. [ABSTRACT FROM AUTHOR]

With the rapid development of machine learning technology, it has become possible to automatically identify cultural heritage elements in traditional buildings. This research aimed to develop a machine learning model based on the YOLOv4 architecture to identify the traditional Chinese porcelain inlay pattern in the Lingnan region. The researchers collected and annotated a large quantity of Lingnan Chinese porcelain inlay image data and then used these data to train the studied model. The research results show that (1) the model in this study was specifically adjusted to effectively identify a variety of Chinese porcelain inlay pattern types, including traditional patterns such as plum blossoms and camellias. (2) In the 116th epoch, the model showed excellent generalization ability, and the verification loss reached the lowest value of 0.88. The lowest training loss in the 195th epoch was 0.99, indicating that the model reached an optimal balance point for both recognition accuracy and processing speed. (3) By comparing different models for detecting Chinese porcelain inlay images across 581 pictures, our YOLOv4 model demonstrated greater accuracy in most classification tasks than did the YOLOv8 model, especially in the classification of chrysanthemums, where it achieved an accuracy rate of 87.5%, significantly outperforming YOLOv8 by 58.82%. However, the study also revealed that under certain conditions, such as detecting apples and pears in low-light environments, YOLOv8 showed a lower missing data rate, highlighting the limitations of our model in dealing with complex detection conditions. [ABSTRACT FROM AUTHOR]

The image classification task of porcelain fragments is of great significance for the digital preservation of cultural heritage. However, common issues are encountered in the image processing of porcelain fragments, including the low computation speed, decreased accuracy due to the uneven distribution of sample categories, and model instability. This study proposes a novel Capsule Network model, referred to as LBCapsNet, which is suitable for the extraction of features from images of porcelain artifacts fragments. A bottleneck-like channel transformation module denoted by ChannelTrans, which resides between the convolutional layer and the PrimaryCaps layer, was first designed. This module is used to reduce the computational complexity and enhance the processing speed when dealing with intricate porcelain images. The MF-R loss function was then proposed by incorporating focal loss into the original loss function. This allows to address the issue of imbalanced distribution of ceramic shard samples and reduce the classification errors, which leads to faster convergence with smoother trend. Finally, an adaptive dynamic routing mechanism is designed with a dynamic learning rate to enhance the overall stability of the classification process. The experimental results obtained on public datasets, such as MNIST, Fashion- MNIST, CIFAR10, FMD and DTD as well as porcelain fragments dataset, demonstrate that LBCapsNet achieves high classification accuracy with faster and more stable computation compared with existing methods. Furthermore, the ability of LBCapsNet to process special textures can provide technical support for the digital preservation and restoration of cultural heritage. [ABSTRACT FROM AUTHOR]

The relationship between social factors and the formation of exported mug designs is blurred. This study addresses how they influence material design. Based on a quantitative typological analysis, this paper interprets the cultural relationships underlying the evolution of mug designs exported during the Ming and Qing dynasties. The study reveals: (1) the typology and handle styles of mugs can be categorized into six types, with a predominance of Cylindrical bodies and Ear-shaped handles. Notably, artistic emphasis is concentrated on Bulbous cup bodies and Tail outward curved handles; (2) the design of mugs in the eighteenth century exhibited diversity, morphological similarities, and feature continuity, evolving from representational (Ming Dynasty) to abstract and then to minimalistic styles (Qing Dynasty), particularly evident in the three-dimensional modeling of handles for ergonomic comfort (transitioning from a singular Outward curved form to Ear-shaped form, and then to Entwined branch form); (3) the body shape of mugs transformed from Arc-barrel bodies to Bulbous bodies (focusing on heat retention), and eventually to Cylindrical bodies (prioritizing heat retention, practicality, and cost-efficiency).; (4) the volume of mugs steadily increased from the early eighteenth century, generally classified into large volume (≥ 500 ml), medium volume (200-499 ml), and small volume (< 200 ml); (5) considering the extreme range of volume (11090 ml) and height (25 cm), it indicates that these two variables do not necessarily have a direct positive correlation; (6) the low center of gravity in handle design (average width of 3.4 cm against an average height of 9.9 cm for the body) reflects considerations for the distribution of liquid weight and operational convenience. The volume of sample-10 (11127 ml) notably exceeds the typical range for tea-drinking utensils, revealing the mechanism of wealth and status symbolism. Market demand orientation emerged as the primary driver for the evolution of export mug designs during the Ming and Qing Dynasties, with adjustments in the merchant system playing a secondary role. The transformation in mug design reflects the interplay of multiple factors, with the trend toward minimalist design being a response to market demands. [ABSTRACT FROM AUTHOR]

This study aims at evaluating the effect of simulating porcelain firing on the microstructure, corrosion behavior and mechanical properties of a Co–Cr–Mo alloy fabricated by Metal Soft Milling (MSM). Two groups of Co-28Cr-5Mo specimens (25 × 20 × 3 mm) were prepared by MSM: The as-sintered (AS) specimens and the post-fired (PF) specimens that were subjected to 5 simulating porcelain firing cycles without applying the ceramic mass onto their surface. Phase identification by X-ray Diffraction (XRD), microstructure examination by optical microscopy and Scanning Electron Microscopy combined with Energy-Dispersive X-ray Spectroscopy (SEM/EDX), corrosion testing by cyclic polarization and chronoamperometry in simulated body fluid (SBF), the latter test accompanied by Cr3+ and Cr6+ detection in the electrolyte through the 1.5-diphenylcarbazide (DPC) method and UV/visible spectrophotometry, and mechanical testing by micro-/nano-indentation were conducted to evaluate the effect of the post-firing cycles on the properties of Co–Cr–Mo. The results were statistically analyzed by the t test (p < 0.05: statistically significant). All specimens had a mixed γ-fcc and ε-hcp cobalt-based microstructure with a dispersion of pores filled with SiO2 and a fine M23C6 intergranular presence. PF led to an increase in the ε-Co content and slight grain coarsening. Both AS and PF alloys showed high resistance to general and localized corrosion, whereas neither Cr6+ nor Cr3+ were detected during the passivity-breakdown stage. PF improved the mechanical properties of the AS-alloy, especially the indentation modulus and true hardness (statistically significant differences: p = 0.0009 and 0.006, respectively). MSM and MSM/simulating-porcelain firing have been proven trustworthy fabrication methods of Co–Cr–Mo substrates for metal-ceramic prostheses. Moreover, the post-firing cycles improve the mechanical behavior of Co–Cr–Mo, which is vital under the dynamically changing loads in the oral cavity, whereas they do not degrade the corrosion performance. [ABSTRACT FROM AUTHOR]

The blue and white porcelain produced in Jingdezhen during China's Yuan Dynasty is an outstanding cultural heritage of ceramic art that has attracted wide attention for its identification. However, the traditional visual identification method is susceptible to misjudgment, thermoluminescence dating damages the samples, and the methods based on chemical analysis are limited by the accuracy and specificity of the elemental features. In this paper, we address the identification challenge by using machine learning techniques combined with portable X-ray Fluorescence Spectrometer (pXRF) analysis. We collect a large dataset of chemical compositions of Yuan blue and white porcelain from Jingdezhen using pXRF, and propose a graph anomaly detection method based on gradient attention map (GRAM) to identify the porcelain from different dynasties. We treat the porcelain produced in the Yuan dynasty as normal samples and those from other dynasties as abnormal samples. For GRAM, we merely train the variational graph autoencoder (VGAE) model with normal graphs and then use its encoder to extract graph features and compute the anomaly scores by utilizing the GRAM of the graph representations with respect to the node feature embeddings. Finally, we compare GRAM with state-of-the-art graph anomaly detection techniques and show that it achieves superior performance. [ABSTRACT FROM AUTHOR]

Ceramic tiles reach their final microstructures and acquire their technical properties by firing process after shaping, glazing, and drying processes. The firing process is carried out continuously in roller kilns. In roller kilns, tiles pass through firing zones at different firing temperatures such as preheating, firing, and cooling zones in which different types of rollers are used. deformations such as breakage and deterioration of roller smoothness occur in the kiln roller over time due to high temperature and tile mass. For these reasons, unused kiln rollers are separated into waste and replaced with new ones. In the present study, the purpose was to transform the kiln roller into a value-added product. For this purpose, the use of kiln roller wastes in glazed porcelain tile matte-opaque glaze was investigated. Ground kiln roller waste was used instead of alumina, quartz, and zircon in a standard matte-opaque glaze composition. The developed glazes were sintered at 1190 °C for 44 min. The thermal, optical, and physical properties of the glazes were examined and compared with the standard glaze recipe. The melting behaviors of the glazes were measured with a heating microscope, and the thermal expansion coefficients were measured with a dilatometer. The phases developed in the structure were determined by XRD analysis and scanning electron microscope (SEM). According to the results, the usage of roller waste instead of alumina and quartz decreased the crystal phase development in the glaze and the opacity, causing an increase in surface glossiness. When it was used instead of zircon, anorthite and crystal phase development increased and the surface brightness decreased, but the opacity decreased significantly due to the decline of zircon crystals. Considering all these thermal and optical properties, it was determined that the use of roller waste would be possible with some optimizations in the composition of matte-opaque glaze composition. [ABSTRACT FROM AUTHOR]

A comparative "cradle to grave" Life Cycle Analysis between the production processes of ceramic stoneware products and geopolymeric materials obtained by valorizing ceramic wastes is reported. This study presents an effective eco-design approach to obtain sustainable materials through a low energy consumption manufacturing process, a feature that is essential in a historical period of high geopolitical instability which makes the supplying of fossil fuels difficult and particularly expensive. In particular, the possibility of lowering production costs (saving on the cost of waste disposal, using a raw-second material, and a low-temperature production process) could represent a strong contribution to the environmental and economic sustainability of the Italian ceramic industry, which is going through a time of severe financial crisis which due to the unprecedent high cost of raw materials and energy. Finally, the new geopolymeric systems proposed in this paper could be profitably used in the field of green building, art, eco-design, and technical-artistic value-added applications, such as restoration, conservation, and/or rehabilitation of historic monuments, or simply as materials for building revetments. [ABSTRACT FROM AUTHOR]

The formation of decorative patterns on export porcelain has risen to the research dimension of cross-regional culture. The interplay between social elements and the formal evolution of export porcelain bowls from the Qing Dynasty in Guangzhou remains nebulous. This study elucidates these underlying cultural dynamics through the lenses of utility and societal implications, thus addressing how societal components contribute to the molding of tangible cultural heritage. Key findings include: (1) A dominance of the ring-foot design in the bases of Qing Dynasty export bowls; (2) The diameter and height of the Qing Dynasty export bowls show relatively concentrated characteristics, reflecting a systemic production trend and relative consistency in form; (3) Some of the Qing Dynasty bowls exceed the parameter range of typical tableware, reflecting the adaptability and innovation of production mechanisms in responding to special market demands. The morphological evolution of the Qing Dynasty export bowls is a true reflection of the interweaving of multiple factors such as comfort design and aesthetic preferences, while the uniformity in shape is a comprehensive reflection of meeting market demands and advances in production technology. This study extends the research dimension to the interaction between standardized production techniques and socio-cultural demands. [ABSTRACT FROM AUTHOR]

The production of cost-effective and eco-friendly transparent ceramic glazes by incorporating pristine waste and eliminating frit preparation was intended to be applied on porcelain bodies. The effect of sintering temperature (950—1150 °C) and waste content (0–15 wt.%) on glazes' phase evolution and optical properties was investigated. At 950 °C, neat glaze consisted of crystalline silica, whereas the waste addition into the glaze composition formed crystalline diopside. Gloss (60°) values generally increased above 950 °C due to the amorphization of crystalline phases; however, sintering at 1150 °C caused a crawling defect for the neat glaze that resulted in gloss reduction. Also, high waste ratios (> 5 wt.%) declined gloss too because of the raised diopside content. The decreasing sintering temperature and the waste ratio higher than 5 wt.% led to higher whiteness due to the white color of the crystalline diopside. Briefly, the addition of 5 wt.% waste to the transparent ceramic glaze recipe provided the highest gloss (77.8) and whiteness (90.2) at 1150 °C, which are higher than even maximum values of neat glaze (40.1 and 88.9) obtained at 1050 °C. Therefore, porcelain bodies with transparent ceramic glazes, produced by the proposed cost-effective and eco-friendly method, carry the potential to be used in various fields as porcelain dinnerware, sanitaryware, and tiles, [ABSTRACT FROM AUTHOR]

Inlay celadon was a type of high-end ceramics of the Koryŏ dynasty (918–1392 AD) produced in the Korean Peninsula. It was conveyed to China during the Yuan dynasty (1279–1368 AD) as tribute or trade goods. In this study, the authors analyzed six samples of inlay celadon recently discovered at the prosperous Taicang Port of the Yuan and Ming dynasties in the lower Yangtze River, China. With scanning electron microscopy coupled with energy dispersive spectroscopy (SEM–EDS) and X-ray diffraction (XRD), the authors investigated the production technique, and compositional characteristics of these samples for the purpose of tracking their provenances. While the bodies are made of porcelain stone, the glazes are of porcelain stone and calcium-rich flux. The white inlay material in these samples is kaolinite-dominant, and the black one is made of quartz with high Fe content or a compound of quartz and raw materials with high Fe content. The results link the samples uncovered at the Taicang Port to the Samhǔngni Kiln in Kangjin-gun and the Uch'ǒlli and Chinsǒri Kilns in Buan-gun in Southern Korea. The products from these kilns were shipped to China in several shipments. [ABSTRACT FROM AUTHOR]

This article brings to attention for Gzhel' porcelain an investigation of the properties and structure of underglaze paints with different cobalt pigments and thedevelopment of a paint composition based on them that resists changes in temperature and the ambient gas medium on firing, and is also less labor-intensive to manufacture. Underglaze paints based on cobalt oxide and pigments synthesized in the chemical systems Co–Al–Si and Co–Si were investigated. Their behavior on painting, color characteristics after firing at 1200 – 1320°C, and resistance to the formation of defects with changes in temperature and the gaseous medium on firing were analyzed. The relationship between the structure of paints on porcelain and its decorative properties was established. Paint with an optimal combination of pigments in the systems Co–Al–Si and Co–Si was introduced into production, corresponding in decorative effect to paint with Co3O, but resistant to metallization defects on firing and less expensive. [ABSTRACT FROM AUTHOR]

The prime motive of this experimental research work is to investigate and compare the wear behaviour of aluminium (AA7075/Al–Zn–Mg–Cu) alloy metal matrix composites enriched with three different ceramics reinforcements (SiC/7wt%, B4C/7wt%, and porcelain/7wt%) prepared via liquid metallurgy stir casting route. Sliding wear performance for all three aluminium-ceramics matrix composites was evaluated on a pin-on-disc tribometer as per Taguchi's L25 orthogonal array by varying normal loads, sliding velocities and sliding distances. The experimental results revealed that porcelain-reinforced composite (AA7075/7wt%porcelain) achieved better resistance property against sliding wear compared to AA7075/7wt%SiC and AA7075/7wt%B4C composites. Further, the fuzzy logic model was developed to evaluate wear loss for three composites with absolute accuracy. Finally, a metaheuristic salp swarm algorithm (SSA) was utilized to minimize wear loss for three composites. The wear loss value attained through SSA exhibits the lowest one in comparison with conventional Taguchi and fuzzy logic results. [ABSTRACT FROM AUTHOR]

In this study, the use of rheologically problematic carbonate-bearing clay from the Bilecik and Çanakkale Region of Turkey in porcelain tile bodies was investigated using the dry preparation method. Firstly, the chemical–mineralogical and technological properties of clays were determined, and characterization studies were performed. Then, an attempt was made to determine the optimum usage possibilities by using these raw materials instead of the standard clay-kaolin mixture raw material at the ratios of 10, 20, 30, and 40% in the standard porcelain tile structure. The sintering behavior of the standard bodies, carbonatic clay containing bodies, was studied comparatively using a double-beam optical non-contact dilatometer. Shrinkage (%), water absorption (%), bulk density (gr/cm3), dry strength (N/mm2), flexural strength (N/mm2), and color L, a, b tests were performed on the developed bodies. Mineralogical and phase analyses have been carried out by XRD. The results showed that carbonatic clays, which have rheological problems, could be used in porcelain tiles with dry preparation systems. [ABSTRACT FROM AUTHOR]

In this study, ceramic foams were produced by adding porcelain polishing waste (PPW) at different proportions (0, 25, 50, and 75 wt.%) to natural zeolite. In addition, Na2CO3, as a foam stabilizer, was externally added to each one raw material mixture to provide a better micro pore structure. The compact parts shaped under 60 MPa load were sintered in an electrical furnace at 10 °C/min heating rate at 1150 °C for 2 h in an air atmosphere. The phase composition and pore morphology of the samples produced were examined using X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The thermal properties from room temperature to 300 °C, flexural strengths before and after corrosion, and corrosion behaviors in dilute NaOH (10% by volume) solution at 100 °C of the produced ceramic foams were investigated. The increase in the PPW amount has caused an increase in the amount and dimension of pores. The total porosity and density of the light foams in four different compositions synthesized varied between 21.80–81.94% and 0.45–1.85 g/cm3, respectively. The flexural strength and thermal conductivity values at 25 °C of the samples were between 0.84–6.18 MPa and 0.21–0.80 W/m.K, respectively. The corrosion behaviors in NaOH aqueous solution at 100 °C of the ceramic foams produced were characterized in detail. It is determined that the weight loss increased with the increase in corrosion time and PPW amount in the samples. Ceramic foam production realized by adding porcelain polishing waste (PPW) to natural zeolite is a promising method for efficient recycling and reducing product cost. [ABSTRACT FROM AUTHOR]

The properties of spent cracking catalyst samples from various refineries are studied. The recycling of spent cracking catalysts to produce ceramic products, namely to manufacture electrical porcelain and fireclay refractories, is justified. The technology for products of subgroup 110 is developed and can be based on the existing technological scheme and equipment. Cracking catalyst wastes (10 – 15 wt.%) can be introduced into the initial charge composition without deterioration of the properties. [ABSTRACT FROM AUTHOR]

Porcelains were prepared by using kaolin clay, potassium feldspar, and quartz as the raw materials, and ZrO2 as a reinforcing material. This study investigated the effects of the amount of ZrO2, the firing temperature, and the holding time on the porcelain bending strengths and fracture toughness values, and compared the reinforcing effects of two types of ZrO2. The results show that the effect of the two types of ZrO2 (pure ZrO2 and Y2O3-stabilized ZrO2) on porcelain reinforcement were similar and that the optimal porcelain reinforcement was obtained with a ZrO2 content of 6 wt.%, firing temperature of 1320°C, and holding time of 30 min. The bending strength increased from (58 ± 6) MPa to (89 ± 8) MPa (pure ZrO2) and (87 ± 8) MPa (Y2O3-stabilized ZrO2), with the respective growth rates reaching 62% and 58%. Radial stress was generated in the matrix during the cooling process because of the difference between the thermal expansion coefficients of ZrO2 particles and the matrix. This increased the porcelain strength. The phase transformation of ZrO2 improved the fracture toughness of the porcelain, but had little effect on reinforcement of the porcelain. [ABSTRACT FROM AUTHOR]

Color variations and sometimes the frosted appearance of Chinese blue-and-white porcelain produced in folk kilns and recovered in underwater archaeological contexts are usually reported without further investigation. This study focuses on the causes responsible for the appearance of the glaze and blue decorations of late fifteenth-century blue-and-white porcelain from the Santa Cruz, one of the most important mid-Ming shipwrecks discovered in Asian waters. Besides detailed visual observations, chemical composition and colorimetric data were collected on a set of similarly shaped plates showing significant differences in the aspect of the glaze and tones and shades of the blue color. Results from portable X-ray fluorescence (pXRF) analysis confirmed the Jingdezhen origin of the ware and the use of domestic asbolane ores for the Co-based blue pigment. Visual and microstructural analysis has shown that the degree of opacity of the glaze is primarily linked to the crystallization of anorthite, which in some cases has pushed the pigment layer towards the surface, contributing to the development of white-brownish weathering spots. The colorimetric data acquired with fiber optics reflectance spectroscopy (FORS) allowed us to quantify chromaticity parameters and confirm the visual perception of a 'not-so-blue' color of the decoration. Without excluding a possible contribution of the underwater environment, the observed variations can be mainly attributed to the ware's production and more specifically to pigment characteristics, manufacturing processes, and firing conditions even though the connection with these factors is not straightforward and prompts further research and broader discussions. From a historical perspective, it is suggested that the atypical hues are correlated with the progressive switch from foreign to domestic pigment sources during the Chenghua period (1465–87 CE) and the subsequent technological adaptations required by an ever-increasing demand for Chinese blue-and-white porcelain at the turn of the sixteenth century. [ABSTRACT FROM AUTHOR]

This paper discusses the influence of aluminum–alkali sludge and chemical production waste on the phase composition of porcelain stoneware based on kaolin clay. Porcelain stoneware with high physical and mechanical properties was obtained at 1250°C. X-ray phase and IR-spectroscopic studies revealed the presence of quartz, cristobalite, mullite, corundum, and glass phase in the porcelain stoneware, with at least 50% of the overall content comprising glass phase. The presence of corundum, spinel, mullite, and anorthite in porcelain stoneware composition imparts high physical and mechanical parameters (strength, frost resistance, heat resistance, etc.). Patent RF 2768886 was obtained for the developed formulations. [ABSTRACT FROM AUTHOR]

The vacuum impregnation method was employed to produce two batches of tubular drills, incorporating AS200 500/400 diamond grains in a Cu–15 wt.% Sn metal matrix. In one batch, ASM 1/0 ultradispersed diamond powders (UDDPs) were added as a reinforcement to matrices in some tools. In the other batch, the reinforcement was tin. The concentration of ASM 1/0 additives ranged from 1 to 11 wt.% and that of tin from 1 to 10 wt.%. Comparative laboratory tests for drilling porcelain, granite, and SiC-based abrasive stone were conducted using these diamond drills. Performance characteristics such as drill wear and drilling speed were examined. The hardness of matrix samples containing additives, but without AS200 500/400 diamond grains, produced by the vacuum fusion method was determined. In drilling the examined materials, UDDPs reduced the wear of diamond drills through the reinforcing effect and increased matrix hardness. The optimal concentration of UDDPs was found to be 5 wt.% (9 wt.% for porcelain). A further increase in the concentration of such additives led to higher wear of the drills as porosity that appeared in the matrix reduced diamond grain retention. The addition of tin to the matrix also decreased the wear of diamond drills, with the minimum wear observed when approximately 4 wt.% Sn was introduced into the matrix. Increasing the tin concentration in the matrix beyond this point resulted in higher drill wear because of brittle intermetallics, which also reduced the strength of diamond retention. The diamond drills with UDDP additives exhibited higher drilling speeds that those with tin additives. Furthermore, the drilling speed for porcelain and granite decreased with the introduction of tin up to 4 wt.% because of the 'blunting' effect. The diamond drills with a UDDP-reinforced matrix demonstrated better performance characteristics, including reduced wear and higher drilling speed. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of firewood ash waste generated in the red ceramic industry on the densification behavior of electrical siliceous porcelain formulations. For this purpose, siliceous porcelain formulations added with up to 8.0 wt.% of firewood ash waste for partial replacing Na-feldspar were prepared. The siliceous porcelain specimens were produced by uniaxial pressing and fired at 1300 °C using a fast-firing cycle. The densification behavior of the specimens fired was monitored by measuring linear shrinkage, apparent density, water absorption, apparent porosity, and volume electrical resistivity. Microstructural and phase characterizations were carried out by SEM and XRD, respectively. The results showed that the densification behavior, properties, and microstructural evolution of siliceous porcelain formulations were influenced by the amount of firewood ash waste added. The firewood ash waste, on the other hand, had little effect on the phase evolution. The optimum densification and technical properties for manufacturing electrical siliceous porcelain using a fast-firing cycle were found between 3.15–4.20 wt.% of firewood ash waste as a renewable auxiliary fluxing material. The environmental and economic benefits of such electrical siliceous porcelain with potential application for low-tension electrical insulator should also be highlighted. [ABSTRACT FROM AUTHOR]

Taking LW10B-383W/YT4000 sulfur hexafluoride circuit breaker produced by Henan Pinggao Electric Co. LTD as the prototype, a 1/5 scale test model was designed and manufactured based on the similarity theory. Considering the seismic response characteristics and structural form of this electrical equipment, this paper discussed the method of damping control of circuit breaker model using SMA cables. First, the shaking table tests were carried out for the Y-shaped circuit breaker model with and without control under three scaled seismic records, and the ABAQUS finite-element analysis model was established by automatic surface meshing method. Then, the seismic response analysis was finished along X and Y directions, and the comparison between the finite element and the test results was adopted to examine the availability of the proposed analysis model. Finally, the dynamic response of the model and the damping effect of SMA cables under z direction earthquake excitation were discussed using finite-element method. The results show the finite-element analysis results of Y-shaped circuit breaker model are in good agreement with the test results, and the SMA cables can effectively suppress seismic response of circuit breaker. When the peak ground acceleration (PGA) is 800 gal, the maximum acceleration suppression ratio of the end of arcing porcelain bushing is about 35% and the maximum displacement suppression ratio is about 32.5%. Meanwhile, the root stress of porcelain casing is also efficiently decreased, the inhibition rate of peak root stress of supports porcelain casing is about 40% for horizontal seismic action, and that of arcing porcelain bushing is about 30% for vertical seismic action. [ABSTRACT FROM AUTHOR]

Some aspects of container-glass cullet processing technology are considered. Schemes for differentiated optical separation of a mixture of colorless, brown, and green cullet are presented. [ABSTRACT FROM AUTHOR]

Purpose: Due to the use of brittle materials and special structure, the porcelain column electrical equipment is easy to be damaged in the earthquake, so it is necessary to carry out the research on the damping control of this kind of equipment. Methods: In this study, the damping control test and finite-element analysis of T-shaped circuit breaker model were implemented using shape memory alloy cables. First, based on the similarity theory, an experimental model with a scale of 1/4.5 is designed and made, and the seismic response control study on the circuit breaker model with the shape memory alloy (SMA) is implemented under different peak ground acceleration (PGA) of earthquake motion. Then, the inertia and springs/dashpots in the special setting module of ABAQUS are selected to simulate the SMA control, and the finite-element analysis of seismic response of circuit breaker model is carried out and compared with the test results. Finally, the study discussed the influence of the effective length and dip angle of the SMA cables on the damping performance for circuit breaker. Results: The results show that the SMA passive cable damping system can effectively reduce the top seismic response of T-shaped porcelain column circuit breaker. When PGA is 8 m/s2 at El Centro wave, the reduction rates of displacement and acceleration response are 38.1% and 21.1%, respectively. Meanwhile, the finite-element analysis results of dynamic response of circuit breaker model are in good agreement with experiment results, which verifies the validity of the established finite-element model. Moreover, the SMA lasso damping device can effectively reduce the porcelain bushing root stress of the circuit breaker in the earthquake, when the length of SMA wire is 200 mm, the dip angle is 60°, the SMA cable system has the best damping effect on the circuit breaker model. Conclusion: The research results are of great significance to ensure the safe operation of the power system under the earthquake action. [ABSTRACT FROM AUTHOR]

The mechanisms of structure formation in porcelain at low temperature using new unconventional raw materials are presented. It was found that structure formation in the experimental porcelain materials is completed at lower firing temperatures (1220 – 1250°C). The phase composition of the synthesized porcelain consists mainly of mullite, quartz, and cristobalite crystals and a vitreous phase filling the gaps between the crystals. [ABSTRACT FROM AUTHOR]

A simplified method is proposed for determining structural parameters of composite ceramics using porcelain as an example according to the average coordination number of random packing and optical microscopy data. This eliminates ambiguity in representation of structural parameters. The calculated average distance between quartz particles in porcelain is in good agreement with an experiment. [ABSTRACT FROM AUTHOR]

This study aimed to compare MRI quality between conventional fast spin echo T2 weighted imaging (FSE T2WI) with periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) FSE T2WI for patients with various porcelain fused to metal (PFM) crown and analyze the value of PROPELLER technique in reducing metal artifacts. Conventional FSE T2WI and PROPELLER FSE T2WI sequences for axial imaging of head were applied in participants with different PFM crowns: cobalt-chromium (Co–Cr) alloy, pure titanium (Ti), gold–palladium (Au–Pd) alloy. Two radiologists evaluated overall image quality of section in PFM using a 5-point scale qualitatively and measured the maximum artifact area and artifact signal-to-noise ratio (SNR) quantitatively. Fifty-nine participants were evaluated. The metal crown with the least artifacts and the optimum image quality shown in conventional FSE T2WI and PROPELLER FSE T2WI were in Au–Pd alloy, Ti, and Co–Cr alloy order. PROPELLER FSE T2WI was superior to conventional FSE T2WI in improving image quality and reducing artifact area for Co-Cr alloy (17.0 ± 0.2% smaller artifact area, p < 0.001) and Ti (11.6 ± 0.7% smaller artifact area, p = 0.005), but had similar performance compared to FSE T2WI for Au–Pd alloy. The SNRs of the tongue and masseter muscle were significantly higher on PROPELLER FSE T2WI compared with conventional FSE T2WI (tongue: 29.76 ± 8.45 vs. 21.54 ± 9.31, p = 0.007; masseter muscle: 19.11 ± 8.24 vs. 15.26 ± 6.08, p = 0.016). Therefore, the different PFM crown generate varying degrees of metal artifacts in MRI, and the PROPELLER can effectively reduce metal artifacts especially in the PFM crown of Co-Cr alloy. [ABSTRACT FROM AUTHOR]

The mechanical behavior and failure mode of multilayered bonded and non-bonded glass-ceramic structures after long-term water-aging is relevant considering how widely used these ceramics are in many fields. This work is focused on ceramic structures used in dentistry. The objective here was to determine the fracture load of ceramic structures not bonded and bonded to a dentin analog material (G10) using low (L) and high-viscosity (UH) dual-cured resin cements (C). Porcelain (P) disks were tested whether bonded or not bonded to G10, as follows: a) P – control group, b) PHF – acid etched, c) P·CL – HF and coated with CL, d) P·CUH – HF and coated with CUH, e) P·CL·G10 – HF and bonded to G10 using CL, and f) P·CUH·G10 – HF and bonded to G10 using CUH. The groups bonded to G10 were stored in deionized water for 24 h, 1, 3, and 6 months. The fracture load was examined using Weibull statistics. The Weibull modulus (m) for group P was similar to that of PHF and significantly higher than for P·CL and P·CUH. P·CL showed higher m than P·CUH. As for the characteristic fracture loads (F0), P and PHF showed statistically similar values that were significantly higher than those obtained for P·CL and P·CUH. For P·CUH·G10, there was no effect of storage time on both the F0 and m. For P·CL·G10, storage time only caused significant changes in F0. After aging, there was no change in the mechanical behavior of the porcelain structures bonded to G10 using CUH. There was a decrease in F0 over time when CL was used. These results reveal that the viscosity of the resin cement plays an important role in the mechanical behavior of the bonded porcelain structures. Overall, ceramic structures bonded using a high-viscosity dual-cured resin cement seems to present better performance over time. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this in vitro study was to evaluate the efficacy of double veneering, low-temperature porcelain, and total glaze application methods to overcome failures of zirconia-based restorations. Materials and methods: Ninety yttrium-stabilized tetragonal zirconia materials with 1.2 × 5 × 24 mm dimensions were cut from pre-sintered blocks. According to the fabrication process of the samples, 3 main groups were formed in the beginning. Low-temperature porcelain and press-on ceramic were used for veneering. First, the samples were divided into 9 sub-groups. Then they were arranged to form triple groups. Triple groups were arranged according to the sample preparation and applied test methods, respectively. After three-point bending tests, marked samples were oriented for stereomicroscope and scanning electron microscope to evaluate and identify the fracture types. Data were statistically analyzed (p < 0.05). Results: Delamination counts were higher than the chipping counts at all the samples with press layer. Chipping count was higher than the delamination count at low-temperature porcelain-veneered triple group. Delamination count was the highest at double-layered triple group. Scatter sample count was the least at ceramic-veneered triple group. Standard triple group was found to be more fracture-resistant. Accelerated aging increased delamination and/or scatter counts at all sub-groups and significantly (p = 0.01 < 0.05) degreased the mean fracture strength values. Total glaze application significantly (p = 0.01 < 0.05) improved the fracture strength values. Conclusion: All-round thinking is very important considering fracture strength, fracture type, delamination, chipping, normal fracture, and scattering. Applying low-temperature porcelain on zirconia substructure is more efficient than a transition material. Press-on material alone as a superstructure is not sufficient for successful restoration. Double veneering method is highly questionable. Clinical relevance: Zirconia-based all-ceramic restorations meet many criteria, especially durability and esthetics, which are necessary for a successful restoration. However, the harmony/integrity of substructure and superstructure is still an issue. Therefore, choosing of the veneering and/or protective method used during the fabrication of the restoration is very determinative for long-term success. [ABSTRACT FROM AUTHOR]

In this study, the possibility of using calcined-colemanite as an alternative fluxing agent in a body mixture used for porcelain tile was investigated. For this aim, a part of industrial spray-dried powders was replaced with the colemanite calcined by microwave-assisted heating (MACC) in varying amounts (up to 3 wt. %). The tile compositions prepared with different proportions of MACC addition were pressed uniaxially at 15 MPa, and the shaped tiles were then fired at 1220 °C for 50 min in an industrial roller kiln. Physical and mechanical tests, X-ray diffractometer (XRD), and scanning electron microscopy (SEM) analyses were performed to examine the effects of MACC addition on porcelain tile's technical properties and phase development. The results revealed that the porcelain tiles having 0.5 wt. % of MACC had better technical properties, i.e., lower water absorption (0.09%) and porosity (0.22% for apparent porosity and 7.25% for closed porosity), and higher bending strength (66.04 MPa) than that of others. Consequently, the MACC addition promoted a low-viscosity liquid phase during firing, resulting in a significant microstructural improvement by decreasing the closed porosity and increasing the bulk density and flexural strength. [ABSTRACT FROM AUTHOR]

Eleven celadons with different degrees of degradation excavated from the Dalian Island shipwreck of the Yuan Dynasty (1271–1368 AD) were selected, and the degradation mechanism of the ancient porcelain at marine environment was investigated. The chemical composition, microstructure, and corrosion morphology of the samples were characterized. The results showed that these celadons can be divided into two types: transparent glazes and matt-opaque glazes. The glazes are subject to the combined effects of physical damage and chemical corrosion. The glaze surface became rougher through physical impact, and the increased surface area may also promote chemical corrosion. The mutual promotion of the two effects usually leads to more serious degradation. There are two possible corrosion mechanisms, depending on the glaze microstructure. Transparent glazes may experience the process of dissolution and reprecipitation. The crystallization-phase-separation structure in the matte glaze has lower chemical stability, which can contribute to more extensive corrosion. [ABSTRACT FROM AUTHOR]

Porcelain wares containing calcined bone ash and gypsum in their pastes were some of the most commercially successful high-fired wares produced in Britain and America during the third quarter of the 18th century. They were produced by the two earliest porcelain manufactories in America (the Bartlam and the Bonnin & Morris factories) and by several British manufactories, including the largest such enterprise (Bow) and another London factory (Isleworth). Owing to the influence that London manufacturers had on contemporary and later porcelain producers elsewhere in Britain and in America, major, minor, and high-precision trace-element data were determined for pastes and glazes of potsherds from the sites of these factories so that compositional commonalities and differences could be ascertained. Multidimensional scaling of major- and minor-element data for 34 samples of these wares generates diagrams on which the products of the four factories under consideration cluster relatively tightly as compared with diagrams created using only trace elements and all analytical data (major, minor, and trace elements). The coupling of geochemically unaffiliated components (or ratios thereof), including trace elements, however, tends to generate the best field separation on discrimination diagrams for these wares. The American and British phosphatic porcelains described here can readily be distinguished based on the concentrations of various paste components; rubidium vs. arsenic and tin, for example, best distinguishes Bartlam from Bonnin & Morris and their London counterparts. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the effects of porcelain veneering methods on the marginal and internal fit of a three-unit zirconia framework. A zirconia master model, in which the lower-left second premolar and the second left molar were used as the abutment, was obtained using an intraoral scanner. Based on the data, three-unit zirconia frameworks for fabricating all-ceramic bridges were designed and milled (FW group). Two types of all-ceramic bridge were fabricated by veneering porcelain onto these frameworks using the press-over technique (P group) and the layering technique (L group). The replica technique was used to measure the gap size between the abutments and the bridges. Measurements were taken in the marginal opening area (MO), chamfer area (CH), axial area (AX), and occlusal area (OC). Statistical analysis was performed using the Mann–Whitney U-test. There was no significant difference in MO and CH between the P and L groups. However, in AX, the L group had a significantly larger gap size than that of the P group (p = 0.003). In addition, compared with the FW group, the P group showed a significantly larger gap size in MO (p < 0.000), CH (p = 0.008), and OC (p < 0.000). These results indicate that the gap size increased after porcelain veneering using the press-over and layering techniques. In addition, the all-ceramic bridges fabricated using the press-over and layering techniques had approximately equal gap sizes in MO. [ABSTRACT FROM AUTHOR]

The effect of zirconium oxide nanoparticles (NZ) addition on the electrical and physical properties of porcelain insulators over high different sintering temperatures was investigated. Different amount of zirconia nanoparticles (0–8 wt%) was added to porcelain sample that obtained from local raw materials found in large quantities and excellent quality in the Sinai and Aswan (Egypt). Samples were produced by powder technology with compositions of 50% kaolin, 25% feldspar and 25% quartz. The prepared samples admixed with different amounts of zirconia were sintered at different temperatures (1100, 1200, 1300 and 1400 °C) for 2 h. The microstructures of some selected samples were characterized by scanning electron microscopy (SEM). Phase composition of some nanocomposites samples was identified using X-ray diffraction (XRD), to evaluate the thermal, structural and microstructural changes by increasing the concentration of zirconia. The electrical properties of different samples were evaluated by measuring the AC breakdown strength, the relative permittivity (εr) and dielectric loss (tan δ) at different frequencies at room temperature. A finite element method (FEM) axisymmetrical model of the samples is used to evaluate their breakdown strength. The results obtained revealed that, samples sintered at 1300 °C give the best electrical and physical properties. Also, nanocomposite porcelain sample admixed with 4 wt% zirconia nanoparticles and sintered at 1300 °C present the maximum density (3.678 g/cm3), minimum water absorption (0.031%) and minimum porosity (0.049%) values as well as good insulating characteristics and confirm the electro technical porcelain production feasibility. [ABSTRACT FROM AUTHOR]

The effect of diopside on the sintering temperature, structure, and properties of low-temperature electrotechnical porcelain was investigated. Diopside concentrate in the amount 12.5 wt.%, which is 10% diopside CaMgSi2O6, was introduced into a porcelain body, excluding quartz (7.2%) and decreasing the content of clay components by 5.3%. It was determined that the firing temperature was lowered by 100°C to 1220°C and the bending strength increased by 30% to 73 MPa due to reactive sintering on the interaction of diopside with the decomposition products of the clay components and anorthite and cordierite were formed. [ABSTRACT FROM AUTHOR]

In the present study, total quartz content (30 wt%) of a standard porcelain body was progressively substituted with two different kinds of aluminas (active alumina and calcined alumina) keeping active alumina constant at 5 wt% and varying calcined alumina content to the extent of 5–25 wt%. The alumina incorporated compositions (AP1 to AP7), along with the standard quartz containing porcelain body (SP0), were processed following common ceramic processing techniques. Two types of forming techniques were used to make samples, namely extrusion of plastic mass to get cylinder of desired dimensions and the other one was hydraulic compaction to produce rectangular bars. The extruded and compacted samples were properly dried and then heated in an electrically operated furnace in the temperature range of 1170–1260 °C. The fully densified samples heated at 1260 °C were subjected to various tests, namely phase identification by X-ray diffraction (XRD) pattern studies; scanning electron microscopic (SEM) analysis; and measurement for electrical properties such as dielectric strength (kV/mm), dielectric loss (tanδ), electrical resistivity (ohm-cm), and dielectric constant to confirm suitability of the samples for application in high-tension power transmission system. The results revealed that the body AP6, wherein 25 wt% quartz was substituted by 5 wt% active alumina and 20 wt% calcined alumina and heated at 1260 °C, may be considered the most suitable sample for porcelain insulator. [ABSTRACT FROM AUTHOR]

Limestone was used to modify the fluxing action of two potash feldspars (a pure potash feldspar and a soda-potash feldspar) labeled P and C, respectively, in the formulation of porcelain stoneware based on Cameroonian raw materials. The effect of limestone addition (0–10 mass%) was investigated in the range of sintering temperature between 1125 and 1300 °C. Characterization of sintered samples including thermal behavior (DTA, TG and dilatometry test), phase evolution, densification parameters, flexural strength, morphology as well as pores structure was investigated in details. The maximum flexural strength (138 MPa) was obtained at 1175 °C with P series (7 mass% addition of limestone) and at 1200 °C (122 MPa) for C series. The maximum density (≈ 3.1 g cm−3) and lower water absorption (≈ 0%) were obtained at 1200 °C. Mullite and anorthite were identified as main crystalline phases. Starting from 1175 °C and mostly at 1200 °C, the two series compositions (with 7 mass% addition) presented a self-glazing phenomenon which gave them significant brightness and high aesthetic quality; these properties were accomplished only at 1300 °C for reference samples with no lime addition (P0 and C0). A proper addition of limestone (3–7 mass%) with potash feldspar significantly reduced the sintering temperature (~ 150 °C) and permits the production of high strength (122–138 MPa), low energy and sustainable porcelain stoneware. [ABSTRACT FROM AUTHOR]

Evaluating the species-specific effects of multiple predators on shared prey helps to identify the mechanisms regulating predator impacts. Here, we investigate the trophic impact of two predators of the Chilean rocky subtidal, the fish Graus nigra [F] and the octopus Robsonella fontaniana [O] on their shared prey, the porcelain crab, Petrolisthes violaceus. Manipulative laboratory experiments were performed to evaluate mortality and behavior of porcelain crab in different treatments, including prey alone; prey with single predator ([O] or [F]); and prey with combined predators ([F + F], [O + O], and [O + F]). Different prey densities (N = 3, 9, and 12 individuals) were used to explore density-dependent predation mortality for single and combined predators using an orthogonal (crossed) design that allows to tease apart the effects of predator taxonomic identity from prey density. Behavioral responses of interacting species were registered every 4 h for 2 consecutive days, and were used to identify predator foraging strategies and prey refuge use. Mortality values (proportional prey mortality and predator per capita consumption) were compared among treatments. Results indicated differences in mortality among treatments. The cause of increase of prey proportional mortality was due to an increase in prey availability outside the refuge in fish treatments at high initial prey densities, while it was density independent in octopus' treatments. Changes in predator per capita consumption were registered depending on the predator combination and the initial prey density. These patterns may reflect contrasting predator foraging strategies and changes in refuge use by porcelain crabs, suggesting effects on prey mortality and predator impacts. [ABSTRACT FROM AUTHOR]

The results of a study of the use of non-destructive contact-free optical spectroscopy — registration of UV-VIS-NIR-range diffuse reflection spectra and photoluminescence spectra — for the identification of porcelain products are reported. Based on the color characteristics and a list of optically active centers of luminescence (OALC) porcelain products were graded according to the composition and state of the redox medium during firing. It is shown that the chromaticity of porcelain can be controlled by means of a combination of color and luminescence centers and their intensity ratio. A decrease in the intensity of the OALC Fe3+ band is mainly related to a change in the coordination of iron Fe3+O4 → Fe3+O6 in bone china. [ABSTRACT FROM AUTHOR]

This study discusses the local production, electrical characteristics and performance in service of porcelain insulators for outdoor low-voltage apparatus. Concern was given to the identification, beneficiation, characterization and utilization of locally available raw materials in Nigeria for the production of electrical porcelain insulators, taking benefits of the availability of these raw materials. The process control presents figures, tables, simulations. The basic raw materials were separately prepared using a 200-µm sieve. The composition of the triaxial constituents was varied to produce samples for testing. Altering the percentage content of silica and the alumina recorded a change in the mechanical strength and the sintering temperature; this was handled by adding fluxes suitable for improving tensile strength without increasing sintering temperature of the paste. Porcelain slab samples of different triaxial composition were formed. Tests on mechanical resistance, porosity and water absorption were carried out. Sample A, with specific percentage composition of 38% feldspar, 18% quartz, 32% kaolin and 12% ball clay, was used to produce porcelain suitable for the 480 V pin insulators. The produced sample possess an electrical dielectric constant of 9.80, a dissipating factor of 0.060, flashover voltage of above 5 kV all at 50 Hz of supply voltage frequency and a mechanical load support of 13.85 kN. [ABSTRACT FROM AUTHOR]

This chapter provides insights into Chinese ceramic technologies of both bodies and glazes as well as provenance by using isotopes applied to a number of case studies. The use of Sr isotopes to investigate Chinese high-fired Celadon wares and blue-and-white Jingdezhen porcelain (Jiangxi province) has revealed a clear distinction associated with the fluxes used in the glazes: plant ash in celadons and limestone in Jingdezhen glazes, something that is not clear from major element analysis. Furthermore, the technique is able to suggest by implication the nature of the silica source used in the glazes—normally weathered granitic rocks or metamorphic rocks (porcelain stone) which also contains Sr. This leads to an isotopic mixing line of the 2 Sr-rich components and is proof that 2 Sr-rich components were mixed in the manufacture of limestone glaze. This is not the case for plant ash glazes. Eventually, the technique may be used in provenance studies. Like Sr isotope analysis, lead isotope analysis relies on there being a lack of or a minimal change in the isotope ratios when the raw materials are heated. Lead isotope analysis links the use of lead in glazes to the original metal ore and if a kiln uses a distinctive lead source in its glazes, it can provide a provenance for the pottery. This has been very successful in distinguishing Chinese Tang sancai wares made in the Huangye, Huangbao, Liquanfang and Qionglai kilns. [ABSTRACT FROM AUTHOR]

The high-voltage electrical porcelain insulator plays an important role in the electrical power industry. The effect of silica nanoparticles (NS) addition on the electrical and physical properties of porcelain insulators sintered at different temperatures was investigated in the present study. Kaolin, feldspar, and quartz (in the form of silica sand) were used as economical raw materials to prepare porcelain insulator samples. Different additions of silica nanoparticles (0–15 wt%) were used. The porcelain specimens were compressed under 50 MPa pressure and treated at different sintering temperature (from 1100 to 1400 °C). The morphology and microstructure of the raw materials and some selected specimens were investigated using scanning electron microscope. Phase composition of some selected samples was identified using X-ray diffraction, to evaluate the thermal, structural, and microstructural changes by increasing the concentration of silica (0–15 wt%). The dielectric properties were evaluated by measuring the AC breakdown strength, the relative permittivity (εr) and dielectric loss (tan δ) at different frequencies at room temperature. A finite element method axi-symmetrical model of the samples with the help of FEMM 4.2 package is used to evaluate their breakdown strength. The results revealed that the physical and dielectric properties of porcelain samples enhanced by increasing the sintering temperature. The porcelain samples admixed with 10 wt% silica nanoparticles and sintered at 1300 °C present the maximal density (3.57 g/cm3), minimal water absorption (0.0173%) and minimal porosity values (0.043%) as well as a good insulating characteristic. [ABSTRACT FROM AUTHOR]

Wear resistance is of great importance for many industries related with minerals. The particles seen in these industries may cause erosion. These particles may have various sizes, shapes, and hardness, and may also impact the surface at various angles and speeds. Wear resistance is also important for the ceramic tile industry because the materials, which are also used in building facades, must withstand all kinds of weather conditions. In this study, the wear resistance of the porcelain tile bodies was investigated by solid particle impingement using alumina particles. The effects of technological, mechanical, and microstructural properties on wear resistance were also investigated. It was determined that the technological, mechanical, and microstructural properties were improved with the addition of spodumene, which also caused that the wear rates were reduced. [ABSTRACT FROM AUTHOR]

The production of Japanese enamels for porcelain decoration was thought to have originated from the direct and exclusive influence of Chinese potters who moved to Japan during the chaotic Ming to Qing dynastic change in 1644. Recent systematic studies have identified, for the first time, the crucial influence of Jesuit missionaries on pigment and enamel production in Japan from the late 16th-century. In particular, such first encounter laid the foundation for the continued influence exerted by European technology on Japanese art throughout the centuries. The present study has further identified European enamels used for the decoration of polychrome wares fired in Arita, the porcelain production center of Japan. This continued exchange not only marked the Edo period, but also extended into the twentieth century. For the first time, the lack of written records regarding the use of western pigments for enamel production caused by the persecutions of European and Japanese Christians has been overcome in the work herein presented. The nature of the imported materials has been firmly identified and characterized. The analytical results (EDXRF and Raman) have finally revealed how western technology and materials not only kept influencing Japanese art during the isolation (sakoku) period, but also accompanied the strong westernization process that marked Japanese history from the late nineteenth century. Moreover, the significant reverse influence of Japanese-made enamels on Chinese polychrome porcelain production in the late Qing and twentieth century has been fully identified for the first time. Furthermore, results show that the shift of the Pb mode of lead antimonate (Naples Yellow) is affected by the firing temperature for enamel decoration, and that this characteristic, along with the chemical composition, enables the identification of the origin and manufacture period of the yellow enamel. [ABSTRACT FROM AUTHOR]

The influence of wollastonites and marshallites on phase transformations and the processes leading to the formation of the mineral composition and structure of electrotechnical porcelain were determined. A positive dynamics of changes in the amount and ratios of crystalline and glassy phases as well as mullitization in bodies was established. Samples corresponding to the standards were obtained under laboratory conditions. The results will serve as a criterion for adoption in industry. [ABSTRACT FROM AUTHOR]

This research was aimed to investigate the leaching behavior of zinc and copper from a porcelain stone tailings sample using RSM-CCD modeling. The synergetic and individual effects of five main factors including liquid/solid ratio, sulfuric acid concentration, agitation speed, leaching time, and temperature were examined on the recoveries of zinc and copper. For this purpose, two 2F1 models with R2 values of 0.9341 and 0.8693 were developed for the relationship between the leaching efficiencies of copper and zinc and effective terms, respectively. The results indicated that the leaching process was significantly influenced by the interactive effects between factors. The leaching recoveries increased by increasing all factors in the range studied. However, the recoveries were nearly independent of the agitation rate, indicating surface chemical reaction as the leaching kinetics controlling step. It was also found that the linear effect of temperature, the interaction effect of leaching time with liquid/solid ratio, and the interactive effect between sulfuric acid concentration and agitation rate had the greatest impact on the leaching rate of copper. Additionally, the linear effect of temperature and the interactive effect of temperature with agitation speed and liquid/solid ratio were distinguished to be the most effective factors on the recoveries of zinc. Moreover, the optimization was performed using desirability function approach, and the highest recoveries of copper (73.95%) and zinc (81.02%) were obtained at an acid concentration of 10%, 300 rpm agitation rate, 10 mL/g liquid/solid ratio, 35 °C temperature, and 75 min leaching time. [ABSTRACT FROM AUTHOR]