Ceramic Raw Materials Research Articles

Technological choices and practices of Early Bronze Age pottery production in the Central Plains: Focusing on the sites of Xinzhai and Huadizui

Aspects of the Early Bronze Age (ca. 2050–1640 BCE) pottery production technology and knowledge transfer in the Central Plains of China (i.e., the Zhengzhou-Luoyang area) were studied. To this aim, 120 domestic pottery samples and ten geological samples from two central sites at Xinzhai and Huadizui were studied macroscopically and analysed with X-ray fluorescence spectrometry. Based on a discussion of macroscopical evidence and chemical composition, the results tentatively indicate the technological knowledge transfer between the potters in Xinzhai and Huadizui sites despite being located about 80 km apart. Pottery of the same category was manufactured with similar selection and preparation strategies of ceramic raw materials, decorated with similar patterns, and adopted similar forming techniques. More specifically, the cookware from the Xinzhai and Huadizui sites was hand-made and Ca-poor, while the storage- and drinking wares were wheel-made and Ca-rich. These results likely indicate the existence of one overarching community of practice, potters located at Xinzhai and Huadizui, who shared strategies for raw materials selection, paste preparation, and finishing.

Fine-grained concrete with the addition of highly dispersed brick scrap powder

The use of brick breakage in concretes and in binder compositions is a promising direction for the development of recycling ceramic bricks. The purpose of the present research was to evaluate the possibility of using mineral powders obtained from brick breakage as an effective dispersed component in the production of fine-grained concrete. In the work, mechanical grinding of ceramic raw material was carried out at different grinding times. It wasestablished that for brick-breakage powders, an increase in the grinding time does not lead to a proportional increase in the specific surface area of the powders.The maximum effective increase in the specific surface area of the obtained powders is fixed at a grinding duration of up to 5 minutes. Using differential thermal analysis, it is shown that crushed brick is not an active mineral additive, but can act as crystallization centers during the formation of hydrosilicates in the structure of composites. Samples of fine-grained concrete were produced, in which part of the cement was replaced with ceramic powders obtained at different grinding duration. It was determined that the replacement of cement in concrete mixtures with this highly dispersed additive in an amount of 20% (by weight), obtained at an optimal grinding time in a ball mill, does not lead to a change in the physico-chemical characteristics of the final concrete composite.

Additive Manufacturing of Ceramic Reference Spheres by Stereolithography (SLA)

Additive Manufacturing (AM) is advancing technologically towards the production of components for high-demand mechanical applications with stringent dimensional accuracy, leveraging metallic and ceramic raw materials. The AM process for ceramic components, known as Ultraviolet Laser Stereolithography (SLA), enables the fabrication of unique parts or small batches without substantial investments in molds and dies, and avoids the problems associated with traditional manufacturing, which involves multiple stages and final machining for precision. This study addresses the need to produce reference elements or targets for metrological applications, including verification, adjustment, or calibration of 3D scanners and mid- to high-range optical sensors. Precision spheres are a primary geometry in this context due to their straightforward mathematical definition, facilitating rapid and accurate error detection in equipment. Our objective is to exploit this novel SLA process along with the advantageous optical properties of technical ceramics (such as being white, matte, lightweight, and corrosion-resistant) to materialize these reference objects. Specifically, this work involves the fabrication of alumina hemispheres using SLA. The manufacturing process incorporates four design variables (wall thickness, support shape, fill type, and orientation) and one manufacturing variable (the arrangement of spheres on the printing tray). To evaluate the impact of the design variables, dimensional and geometric parameters (GD&T), including diameters, form errors, and their distribution on the surface of the sphere, have been characterized. These measurements are conducted with high accuracy using a Coordinate Measuring Machine (CMM). The study also examines the influence of these variables in the dimensional and geometric accuracy of the spheres. Correlations between various parameters were identified, specifically highlighting critical factors affecting process precision, such as the position of the piece on the print tray and the wall thickness value. The smallest diameter errors were recorded at the outermost positions of the tray (rear and front), while the smallest shape errors were found at the central position, in both cases with errors in the range of tens of micrometers. In any case, the smallest deformations were observed with the highest wall thickness (2 mm).

Physico-chemical characterization of feldspars for application as fluxing agents: Experimental and ab initio computational approaches

Feldspars are tectosilicates with unique composition and structural features employed to help develop the glassy phase while firing ceramic raw materials. This promotes vitrification by lowering sintering temperatures thereby making it more energy efficient and sustainable. This study examined the physico-chemical parameters of feldspars found in Marimanti, Tharaka Nithi county in Kenya with the aim of determining their fluxing capabilities. This was achieved through the use of ab-initio theoretical computations and experimental investigation into phases, morphology and thermal stability. Experimental results showed albite and anorthite mineral phases with dominant alumina and silica content, classifying it as a plagioclase type. Further experimental results revealed four predominant phases viz: Ca-feldspar, K-feldspar, Na-feldspar and quartz with mesoporous morphology and average particle sizes of 5 μm. Thermal stability studies showed a significant derived weight loss per °C in the 400–700 °C range with a peak at 497.67 °C. Three-dimensional atomistic simulations conducted on albite, anorthite and feldspar mineral phases were computed using the Cambridge Serial Total Energy Package (CASTEP) module of Material Studio software, using generalized gradient approximation (GGA) with Perde-Burke-Ernzerhof (-PBE) correction function. Accordingly, ab initio studies showed the minerals had a 3D triclinic lattice structure with predicted bulk moduli of 45.91 GPa and 88.86 GPa for albite and anorthite, respectively. In furtherance, the computed band gap energies were 2.644 eV for albite and 2.661 eV for anorthite, indicating high insulation capacity for both mineral phases. Overall, the experimental and computational results obtained were in agreement with literature on fluxing properties. Further, the outstanding properties reported indicated high quality feldspars which can be exploited sustainably for application as fluxing agents.

Slips, films, and material choice: Long-distance hydrothermal pigments on Middle Mississippian red ware

Using laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) and Raman spectroscopy, we investigate red pigment applied to ceramic vessels as a slip or film (pigment + liquid + binder mixture) in the midcontinental United States. We find that during the CE 1000–1200 period, potters at Cahokia and nearby sites in the American Bottom region of the Middle Mississippi Valley used pigments originating from hydrothermal deposits. The closest hydrothermal deposits are located over 50 km away in the Ozark Highlands and the pigments may have been collected from areas already exploited for other resources. Approaching slips or films as pigment + liquid + binder mixtures integrates ceramic raw materials research with pigment research and encourages us to consider a variety of pigment options, some of which require binders for use on ceramics.

Manufacture of zircon bulk parts and scaffolds by digital light processing

Zircon (ZrSiO4) is a low cost and widely available ceramic raw material used in thermal applications due to its low thermal conductivity and high thermal shock resistance. The aim of the present work was to obtain solid and reticular zircon pieces by digital light processing (DLP), scarcely reported in the literature. For this aim, the dispersion of zircon powders in two different solvents (benzyl alcohol and cyclohexanol) was studied using different UV-curable polymeric systems. The effect of different dispersant concentrations as well as different dispersion/homogenisation methods were evaluated by rheological characterisation. Bulk bodies and scaffolds were obtained by DLP, studying the effect of different printing parameters on the quality and resolution of the produced parts. Debinding and sintering steps were optimised using different thermal cycles. Dense zircon scaffolds (>96%TD) were obtained from the cyclohexanol based slurries. Finally, the obtained materials were characterised in terms of crystallographic composition and microstructure.

Fabrication of Vitrified Bond Diamond Grinding Wheel via LCD Photopolymerization

In this paper, a liquid crystal display (LCD) photopolymerization method is proposed, and a vitrified bond diamond grinding wheel is successfully prepared. A high-performance vitrified bond was obtained by melting SiO2-B2O3-Al2O3-Na2O ceramic raw materials and used for grinding wheel preparation. LCD photopolymerization technology is characterized by high precision in shaping, fast processing speed, and superior quality, making it a promising technology for fabricating vitrified bond diamond grinding wheels. The preparation of vitrified bond slurry with high solid content and low viscosity was extensively investigated to meet the fabrication requirements. The effects of dispersant, the particle size of the vitrified bond, and solid content on the viscosity of the slurry were systematically analyzed. The vitrified bond slurry with solid content up to 65 wt.% (approximately 45.5 vol.%) was successfully prepared and met the requirements for printing. Furthermore, we explored the optimal formulation of the grinding wheel, debinding and sintering conditions, sintering temperature, grit-to-bond ratio, and the evaluation of the grinding performance of the wheel on hard and brittle materials, such as silicon carbide ceramic. Vitrified bond and abrasive slurry systems with a solid content of 65 wt.% (approximately 42.8 vol.%) were prepared. The results show that the vitrified bond diamond grinding wheel exhibits optimal comprehensive performance, with a sintering temperature of 680 °C and a grit-to-bond ratio of 4:6. The minimum surface roughness of the workpiece after grinding was 1.767 μm, the material removal rate was 5.08 mg/s, the grinding ratio was 9.78, and the friction coefficient was stabilized at about 0.5 during grinding. This paper guides the manufacturing of vitrified bond diamond grinding wheels via LCD photopolymerization.

Potential clay from Bali to support clean production in the Bali ceramic industry

The challenges for the Bali ceramics industry come from the emission side of the materials, production, and waste processing. In the future, the Balinese ceramics industry must develop to be greener and more sustainable. One of the way is reducing emissions from raw materials process. This research was conducted with the aim of mapping the potential of clay that can be used as a raw material for making ceramics, especially those from Bali. The method used was to review the literature on ceramic raw materials and conducted a survey to compile flow diagrams of materials, energy, and emissions from ceramic production in Bali. Then calculated the carbon dioxide (CO2) emissions that arise with the clay scheme come from inside and outside Bali. The results of the study indicate that there is potential for the use of clay from Buleleng and Tabanan areas, which can reduce carbon dioxide (CO2) emissions of the Balinese ceramic industry. However, its use needs to be re-examined from a process perspective because it has a higher iron oxide (Fe2O3) composition.

Non-destructive detection for mosaic ceramic surface defects based on convolutional neural networks

Abstract Mosaic ceramic art pattern with noble, elegant features, it is a unique form of art creation in ancient Greece and the ancient Rome period has been loved by artists and created a lot of classic large-scale exterior mosaic ceramic art works. Small size square mosaic ceramic as the basic raw material for the creation of large exterior mosaic art, it directly affects the quality of the work created by the artist, so these ceramic mosaic ceramic materials need to undergo rigorous inspection to meet the needs of the artist’s high-quality art creation. However, small size multi-color square mosaic ceramics are different from ordinary large target ceramics, they have the characteristics of small size and easy reflection, currently mainly using manual inspection, the existing automatic inspection methods have the problem of low efficiency and accuracy, cannot meet the needs of artists for the quantity and quality of mosaic ceramics. To solve these problems, this paper proposes a new convolutional network-based fast nondestructive testing method for detecting square mosaic tiles. The detection method is based on the convolutional neural network YOLOv5s model, and by introducing the AF-FPN module and the data enhancement module, the method further improves the recognition performance of the model relative to the original YOLOv5s model and achieves the fast detection of surface defects on square mosaic ceramics. The experimental results show that the detection method for small size multicolor square mosaic ceramic tile surface minor defects detection rate of up to 94 % or more, a single square mosaic ceramic detection time of 0.41 s. The method takes into account the detection accuracy and speed, can be fast and accurate screening of high-quality, defect-free small size multicolor square mosaic ceramic, to meet the artist’s requirements for high-quality mosaic ceramic raw materials Quality and quantity requirements, to ensure the quality of the creation of mosaic art patterns, to better show the charm of the mosaic art patterns role. At the same time, the method can not only be applied to the detection of mosaic ceramics, the method can also be applied to have a similar small volume, easy to reflect the characteristics of small target object defect detection.

Study on sintering behavior and properties of lithium slag-based foamed ceramics

To research the value of lithium slag in the development of construction materials, foamed ceramics with different lithium slag/kaolin have been prepared using the conventional high-temperature foaming method. In this study, the effects of sintering temperature and formulation on the morphology and mechanical properties of foamed ceramics are investigated by relying on the formula scheme designed by the Na2O-Al2O3-SiO2 ternary phase diagram. The characterization of the ceramic raw materials and samples by XRF, XRD, SEM, and TGA-DSC reveals that the doping contents of lithium slag have a great influence on the densification of the sample. With the amount of lithium slag increases, the amount of liquid phase in the melt increases, which intensifies the liquid phase flow and accelerates the mass transfer process, promoting the sintering and densification of ceramics. However, too much lithium slag is easy to agglomerate, which is not conducive to the close bonding between the internal components of the ceramic, resulting in a decrease in bulk density. In addition, the doping of spodumene effectively reduces the sintering temperature of the mullite matrix, promotes the formation of mullite crystals, and enhances the mechanical properties of the ceramics. The lithium-slag ceramics sintered at high temperature in this experiment had a maximum compressive strength = 5.70 MPa. average porosity = 73.68%, average apparent density = 0.40 g/cm3 and average water absorption = 2.24%. Overall, the lithium slag foamed ceramics prepared by the high-temperature foaming method have good mechanical properties, which are essential for resource utilization and high value-added utilization of solid waste.

Customized copper/cobalt-rich ferrite spinel-based construction ceramic membrane incorporating gold tailings for enhanced treatment of industrial oily emulsion wastewater

New ceramic membranes (CM) using environment-oriented materials instead of rare materials are more attractive and easier to large-scale engineering and promotion. In this study, the feasibility of customizing low-cost and robust CM, is investigated by sintering typical available solid wastes (Fe-S-rich gold tailings and Si-rich marine shellfish powder) as the matrix with copper/cobalt-rich precursors. Analysis results indicate that the precursors (Cobaltate and Cuprate) with the proposed ratio (1:1 by mass, 1300 °C) can be chemically stable crystallized in the more durable structure of customized copper/cobalt-rich ferrite spinel-based construction CM (CM-(Cu-Co)Fe2O4). The composite membrane can operate stably and consumes no additional energy. After detailed characterization of the pore structure, the purification treatment of industrial oily wastewater (rejection rate > 99.9), emulsion oily wastewater (rejection rate > 97.9) and alizarin red wastewater (rejection rate > 99.3) was fully evaluated. Surprisingly, the waste-to-resource CM of CM-(Cu-Co)Fe2O4 exhibits significant heavy metal iron ion removal performance (>94%) due to electrostatic attraction and adsorption. The successful preparation and application of environment-oriented multifunctional CM from a typical solid waste matrix provide a promising strategy of resource recovery for beneficial utilization of ordinary solid wastes with stock as ceramic raw materials.

Porous Material Made from Non-Firing Ceramics

The establishment of a carbon-neutral society has reached a stage when it is economically and industrially realistic. Based on this background, research on "non-firing ceramics" has attracted attention from the perspective of environmentally friendly manufacturing, such as energy conservation, low cost, and reduction of greenhouse gas emissions, because high temperatures and high pressures are not required. This technology involves a method to grind the surface of a ceramic raw material powder to obtain a chemical activity and solidify it. This paper provides an overview of non-firing ceramics, the mechanism of the surface activation of ceramic raw materials, and its application to porous materials. Although this method is not a substitute for all sintered ceramics, I hope that it will contribute to providing a new direction of manufacturing.

Evaluation insight into Abu Zenima clay deposits as a prospective raw material source for ceramics industry: Remote Sensing and Characterization

The rapid development and mutations have heightened ceramic industrialization to supply the countries' requirements worldwide. Therefore, the continuous exploration for new reserves of possible ceramic-raw materials is needed to overwhelm the increased demand for ceramic industries. In this study, the suitability assessment of potential applications for Upper Cretaceous (Santonian) clay deposits at Abu Zenima area, as raw materials in ceramic industries, was extensively performed. Remote sensing data were employed to map the Kaolinite-bearing formation as well as determine the additional occurrences of clay reserves in the studied area. In this context, ten representative clayey materials from the Matulla Formation were sampled and examined for their mineralogical, geochemical, morphological, physical, thermal, and plasticity characteristics. The mineralogical and chemical compositions of starting clay materials were examined. The physicochemical surface properties of the studied clay were studied utilizing SEM–EDX and TEM. The particle-size analysis confirmed the adequate characteristics of samples for white ceramic stoneware and ceramic tiles manufacturing. The technological and suitability properties of investigated clay deposits proved the industrial appropriateness of Abu Zenima clay as a potential ceramic raw material for various ceramic products. The existence of high kaolin reserves in the studied area with reasonable quality and quantity has regional significance. It would significantly help reduce the manufacturing cost and overwhelm the high consumption rate. The ceramic manufacturers in the investigated areas are expected to bring steady producers into the industry in the long term to gain the advantage of low-cost raw materials, labor, and factory construction.

Research on the Sustainable Utilization of Ceramic Waste under the Green Development Model

China is a big ceramic country, and the production of ceramics has been the first in the world. With the development of the ceramic industry, there are also more and more waste materials. Such a large amount of ceramic waste is not a simple landfill that can solve the problem. Through the analysis of the current situation of solid waste in our ceramic industry, we see that the modern decoration and ceramic raw material regeneration technology to the life cycle of ceramic product design and arrangement make the resources and energy most effectively consumption configuration, so as to achieve the purpose of ceramic waste reduction, recycling, harmless, make ceramic industry production on the road of sustainable development.

Developing Recipe from Local Ceramic Raw Materials for Making Crucibles in Ghana

Developing Recipe from Local Ceramic Raw Materials for Making Crucibles in Ghana

Ceramic Raw Materials from the Pulsating Hot Gas Stream

Ceramic Raw Materials from the Pulsating Hot Gas Stream

Incorporation of Bentonite Mining Waste in Ceramic Formulations for the Manufacturing of Porcelain Stoneware

Mining processes produce a massive amount of waste which, if not treated properly, can cause significant environmental and social impacts. Recently, some studies have focused on the use of mining waste as an alternative raw material. This work developed new sustainable ceramic formulations based on bentonite mining waste (BMW) for applications in porcelain stoneware. The BMW was incorporated into the ceramic masses in different percentages (0, 2.5, 5, 10, 15, 20, 25, and 40 wt.%), in partial replacement to feldspar and total to quartz. X-ray diffraction (XRD), differential thermal calorimetry (DTA), and thermogravimetry analysis (TGA) techniques were used to characterize bentonite waste. Samples (50 mm × 20 mm × 5 mm) were obtained by uniaxial pressing. Such samples were dried and sintered at 1150, 1200, and 1250 °C. The physical–mechanical properties (apparent porosity, water absorption, linear shrinkage, apparent density, and flexural strength) were evaluated for sintered samples. The phases formed after sintering treatments were characterized by XDR and scanning electron microscopy (SEM). The BMW presented a mineralogical composition suitable for use as ceramic raw material. In summary, our results presented that the new sustainable ceramic formulations sintered at 1250 °C have the potential for use in stoneware and porcelain stoneware.

Influence of firing temperature on the ceramic properties of illite-chlorite-calcitic clays

The influence of firing temperature on the ceramic properties of illite-chlorite-calcitic clays has been investigated. Three samples of the same clay deposit have been selected. Weight loss, dimensional changes, water absorption, bulk density, open porosity, flexural and compressive strengths, initial capillary water absorption rate and thermal conductivity have been determined as a function of firing temperature in the range 900-1200 °C with 1 h of soaking time. The microstructures of the fired samples have been examined by SEM and the phase evolution studied by XRD. The water absorption capacity decreased from ∼ 22% at 900 °C/1 h to a maximum of 12% at 1200 °C/1 h with a maximum linear shrinkage of ∼ 2.7%. The open porosities decreased from ∼ 36% at 900 °C/1 h up to ∼ 20% at 1200 °C/1 h as an effect of progressive sintering with higher densification degree of the ceramic bodies. The flexural strength reached a maximum value of ∼ 34 MPa at 1200 °C/1 h. In contrast, the compressive strengths increased by firing up to a maximum of ∼ 114 MPa at 1200 °C/1 h. The thermal conductivity increased slightly as increasing firing temperature with a maximum value of 0.582 W/m·K in samples fired at 1200 °C/1 h. The Ryshkevitch-Duckworth equation was applied and the results indicated that compressive strength is related linearly with open porosity. A linear correlation was found between thermal conductivity and open porosity. The microstructural evolution by SEM indicated that there is a change of the fired samples at 1100 °C as compared to SEM observations at 900 and 1000 °C. There is an increase of contacts between particles and layered structures associated to dehydroxylated clay minerals (illite and chlorite), quartz particles and pores developed by firing. At 1200 °C/1 h, the microstructures have changed associated to the higher degree of vitrification in the fired sample, with consolidation of the material, interparticle and neck contacts with formation of vitrified bridges. The formation of closed and large open pores of several sizes has been achieved by firing. Small particles were observed as a fine precipitation of crystals in the vitrified structures associated to anorthite, hematite and quartz relicts. This change in microstructure allowed deduce that the compressive strength increased upon firing, with maximum values of this ceramic property at 1200 °C. The ceramic bodies were more sintered by firing and the open porosity decreased progressively. Brickmaking is the main application of these fired illite-chlorite calcitic clays. These clays fired at 900–1100 °C, with 1 h of soaking time, could be applied in the fabrication of clay roofing tiles, tiles and even porous ceramic supports with small variations on shrinkage and porosity, good flexural strengths and high compressive strengths. Samples fired at higher temperatures, 1100 °C/1 h, could be applied as ceramic bricks showing a medium porosity (∼ 20%). They show almost the same bulk density when they are fired at lower temperatures (900 °C). Samples fired at higher temperatures (1150–1200 °C/1 h) could be applied as dark ceramic products. This investigation was interesting because a better knowledge of illite-chlorite-calcitic clays applied as ceramic raw materials has been achieved.

The mullite nanofibers for electrotechnical applications

This paper is focused on the development and modification of inorganic refractory nanofibers for advanced applications, made from the most available ceramic raw materials (Al2O3 and SiO2) in the right proportion for crystallization of mullite, commonly used high-temperature material. The intention is to create a modifiable refractory material for use in electrotechnical applications as electrodes, separators, or a solid electrolyte in a new type of safe solid-state batteries. For these reasons, the nanofibers are modified with different conductive materials, for example different types of spinels. Spinels with the formula AB2O4, specifically CuCr2O4, have been studied due to their significant electrical and magnetic properties, that are suitable for their intended purposes.

Increasing the strength of building ceramics made on the basis of low-melting clays

The object of the study is the physical and chemical processes of formation of the structure and properties, intensification of sintering of ceramic masses based on local raw materials (Krynichanska low-melting clay raw materials of the Kyiv region, Ukraine) by regulating the chemical and mineralogical composition and technological regimes. When choosing clay raw materials for specific ceramic technologies, it is necessary to be guided by a comprehensive assessment of the physicochemical properties of clay rock. These can be the granulometric and material composition, including the chemical and mineralogical composition of the clay and impurity components, the presence of amorphous material. The state of order in the structure of clay-forming minerals is also important, the knowledge of which makes it possible to determine the ways of regulating the basic technological properties of clay rock in order to bring them to the required level. Among physical and mechanical parameters, mechanical strength is one of the main criteria for determining the suitability of raw materials for the production of building ceramics. The conducted studies have shown that with an increase in the amount of rotten stone additive introduced from 10 to 20 % of low-melting clay, the mechanical strength of ceramic samples in compression and bending increases. The introduction of rotten stone additive provides an increase in the coefficient of sensitivity to drying low-melting clay raw materials, which has a positive effect on the crack resistance of raw bricks when drying clay rock in order to bring them to the required level. The use of silica materials in the composition of ceramic masses based on low-melting clays as an additive to improve the physical and mechanical characteristics of the finished product has shown its effectiveness. This can be explained by the fact that the nature of the interaction of silica additives, which was used as rotten stone, differs from the interaction of clay minerals present in ceramic raw materials with water. Since silica exists in rotten stone in the form of amorphous silica gel, it helps to improve the structure of clay, makes it monolithic, increasing mechanical strength. The impurities of low-melting oxides, which are part of the rotten stone, contribute to the formation of low-melting eutectic, reducing the refractoriness of amorphous silica and have a positive effect on the sintering process, forming a glass phase.