Ceramic Technique Research Articles

Exploring pottery origin by composition and technique comparison: a case study at the Daqu burial site, Beijing, China

Scientific analysis of excavated pottery reveals critical archaeological insights, yet data on Han Dynasty pottery remains limited. This study focuses on pottery artifacts excavated from the Daqu burial site in Beijing, renowned for their polychrome decorations and size. Utilizing optical microscopy (OM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray Fluorescence (XRF), this study examined five substrate samples sourced from fragments of pottery towers and ellipse-shaped dishes. All samples exhibited similar inclusions and the same firing atmosphere. The mineralogical analysis indicated that quartz and feldspar are predominant components, with minor constituents like chlorite and kaolinite observed in the coarse pottery of the ellipse-shaped dish. Minor mineral variations suggest differences in firing temperatures. The resemblance between low-value pottery cups and delicate polychrome towers suggests they were crafted locally. These findings advance our understanding of ceramic materials and techniques in late Eastern Han Dynasty Beijing, providing crucial insights for future studies on ancient Chinese economy and society.

Maximization of the blue-white contrast of ancient porcelain decorations from Jingdezhen imperial kiln by Co-spinel formation

By analyzing the chromaticity values of the ancient blue-and-white porcelain combined with the imitated experiment, the color information is quantified and ‘color dispersion’ mechanism is clarified. Energy Dispersive X-Ray Fluorescence (EDXRF), field emission scanning electron microscopy (FE-SEM), the advanced focused ion beam transmission electron microscopy (FIB-TEM) technique, etc, were used to study the characteristics and the ‘color dispersion’ mechanism of the blue-and-white porcelain in Jingdezhen imperial kiln. The ‘color dispersion’ of the blue-and-white porcelain is mainly caused by Co-element structure stability, which is verified by the archaeological experiment results. Blue-and-white decoration lines diffusion length (named as ‘color dispersion’) are long (i.e. fuzzy) which has few or no spinel crystals in the body-glaze interaction layer of the blue-and-white porcelain. However, the blue and white porcelain with the clear lines has a large number of spinel crystals. The experimental results enrich the literature on the history of ceramic manufacturing techniques in Jingdezhen.

Optimizing Interfaces in Laser-Brazed Ceramic-Stainless Steel Joints for Hydrothermal Sensors through Finite-Element Modeling

The development of reliable joining techniques for ceramics and metals is crucial for energy applications, such as fuel cells, nuclear reactors, and high-temperature sensors, most especially for the sealing of hydrothermal sensors to study multiphase flows. However, during one-step active laser brazing it is a serious problem that a high thermal stress concentration can occur at the joint interfaces or on the ceramic side of the joint due to mismatches between the CTEs (coefficients of thermal expansion) and/or elastic constants. The uncontrolled thermal residual stress can lead to cracks and defects in the brazement. In the present work, an elastoplastic finite element method/numerical model was formulated to study the thermal residual stresses developed in the brazement between ceramics and austenitic stainless steel during cooling in active laser brazing. Calculations and comparison experiments were conducted to validate the simulated stress distribution in un-patterned ceramics. Stress analyses were conducted for planar and cylindrical specimen geometries (lab joints) relevant for miniaturized energy sensors. Laser interface patterning was employed to create micro-scale features on ceramic interfaces that reduce thermal stress concentrations. The optimization of the interface designing parameters including hatch size, structure width, pattern depth and metal/ceramic thickness ratio was performed using the Taguchi method with orthogonal arrays. The study suggests that laser interface structuring can modify thermal residual stresses in ceramic-to-metal brazements, thereby increasing the reliability of active brazing joints.

Micro milling of different workpiece materials with all-ceramic Y-TZP and cemented carbide micro end mills

Micro milling is a very flexible micro cutting process widely deployed to manufacture miniaturized parts. However, size effects occur when downscaling the cutting processes. They lead to higher mechanical loads on the tools and therefore increased tool wear. Micro milling tools are usually made of cemented carbides due to their mechanical strength and fine grain structure. Technical ceramics as alternative tool materials offer very good mechanical properties as well, with grain sizes well below 1 μ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\upmu$$\\end{document}m. In conventional machining, they have proven to be able to reduce tool wear. To transfer these wear improvements to the micro scale, we manufactured all-ceramic micro end mills in previous studies (∅\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\varnothing$$\\end{document} 50 and ∅\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\varnothing$$\\end{document} 100 μ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\upmu$$\\end{document}m). Tools made from zirconia (Y-TZP) showed the sharpest cutting edges, and were the best performing in micro milling trials amongst the substrates tested. However, the advantages of the ceramic substrate could not be utilized for the brass and titanium materials tested in those studies. Therefore, in this study the capabilities of all-ceramic micro end mills (∅\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\varnothing$$\\end{document} 50 μ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\upmu$$\\end{document}m) in different workpiece materials (1.4404, 1.7225, 3.1325 and PMMA GS) were researched. For the two steels and the aluminum alloy, the ceramic tools did not offer an improvement over the cemented carbide tools used as reference. For the thermoplastic PMMA however, significant improvements could be achieved by utilizing the Y-TZP ceramic tools: Less tool wear, less and more stable cutting forces, and higher surface qualities.

IDEX enhances its material science expertise by acquiring STC Material Solutions

IDEX Corp has enhanced its expertise in material science by acquiring STC Material Solutions, a US company that designs and manufactures technical ceramics and hermetic sealing products for the most extreme, mission-critical applications.

Effects of processing conditions on flash sintering of commercial ZrN

AbstractFlash sintering (FS) is a potentially rapid and low‐cost manufacturing technique for advanced ceramics. There are still many unknowns about ceramic FS, especially for highly conductive high‐temperature ceramics (HTC), which often display decreased bulk conductivity with increasing temperature. This study qualitatively characterizes the flash behavior of highly conductive HTC materials using zirconium nitride (ZrN) as an example. The effects of processing parameters (e.g., DC voltage/electrical field strength, voltage ramp rate, post‐flash holding time, mechanical pressure, sample milling, and choice of electrode materials) on ZrN flash behavior are also qualitatively studied and linked to samples microstructure and hardness. It is observed that best densification was achieved using 5 min Spex‐milled ZrN powder under 25 MPa of applied pressure and constant 8 V DC. The potential mechanism for ZrN FS and the similarity and difference from FS of conventional oxides like YSZ have been proposed based on experimental observations, and the directions for future research are also pointed out.

Food Memories and Diaspora of Culinary Traditions: Echoes from Voices of Displacement in the Rural Scape of Dholavira, India

ABSTRACT This article considers the food memories and diaspora of culinary traditions among the communities residing in present-day Dholavira village, Gujarat, India. Dholavira village, located near the Dholavira Harappan World Heritage site, is home to several ethnic communities. Over the last few decades, there has been a proliferation of the idea of food archaeology in the subcontinent’s culinary research, but most studies conducted so far have highlighted the regionality of culinary landscapes and are grounded in archaeometric techniques. This study moves in a new direction and applies ethnoarchaeology to explore food memories disseminated through the use of simple cooking tools and heirloom recipes. Additionally, the study documents the ceramic production techniques and associated memories of the one local potter, who is based in Janan village near Dholavira.

Exploring the Mpemba effect: a universal ice pressing enables porous ceramics.

Piezoceramics with global porosity and local compaction are highly desired to exploit the combination of mechanical and electrical properties. However, achieving such a functional combination is challenging because of the lack of techniques for applying uniform pressure inside porous ceramic green parts. Nature provides many examples of generating strong forces inside the macro and micro channels via the state transformation of water. Inspired by these phenomena, we present a technique of "ice and fire", that is, water freezing (ice pressing) and high-temperature sintering (fire), to produce ideal porous piezoceramics. We introduce a new compaction method called the "ice pressing method", which manipulates liquid phase transition for compaction. This method has several advantages, including uniform pressure distribution, a wide pressure range, high effectiveness, and selective freezing. It can generate an ultrahigh pressure of up to 180 MPa on the piezoceramic green skeletons in minutes while retaining their functional pore structures. By exploiting the Mpemba phenomenon, we further accelerate the compaction procedure by 11%. The first ice-pressed and second fire-consolidated lead zirconate titanate (PZT) ceramics are highly densified and exhibit an outstanding piezoelectric response (d33 = 531 pC N-1), comparable to conventional pressed bulk counterparts and 10-20 times higher than those of unpressed materials. The novel ice pressing method breaks the limitation of lacking a compaction technique for porous ceramics. The versatile and effective ice pressing method is a green and low-cost route promoting applications in sensors, acoustics, water filtration, catalyst substrates, and energy harvesting.

Analysis of production routes for silicon carbide using air as carbon source empowering negative emissions

A rapid defossilisation of the industry sector is required to stop further greenhouse gas emissions and to curb global warming. Additionally, to avoid irreversible consequences caused by climate change, the deployment of negative emission technologies is required to reduce the carbon dioxide (CO2) concentration in Earth’s atmosphere to a sustainable level. A novel approach to store gaseous CO2 from direct air capture facilities in solid silicon carbide (SiC) is presented. A chain of established processes to produce SiC from renewable electricity and air is evaluated in terms of energy and mass balances. Furthermore, possible fields of SiC utilisation are considered. Electricity-based SiC (e-SiC) can serve the growing global market for technical ceramics and can possibly be used to tackle increasing construction sand shortages in the construction industry by partially substituting sand. Calculations of the levelised cost of carbon dioxide removal show that storing ambient CO2 in solid SiC that can be subsequently sold on the world market can eventually create profit. In 2050, a net benefit of 259 €/tCO2 or 631 €/tSiC can be realised if the SiC product is sold at the world market with additional carbon compensation. Therefore, the proposed SiC production chain might be able to challenge conventionally produced SiC, while empowering negative emissions. In 2050, the net CO2 emission potential is limited to about 290 MtCO2/a for technical ceramics, but may reach up to 13.6 GtCO2/a for construction sand. Results show that e-SiC production is economically feasible for technical ceramics but not for construction sand without further process cost decrease. Alternative processes to produce e-SiC are described and evaluated. Future research opportunities are discussed.

Tailored Synergy: Synthesis and In-Depth Structural Analysis of x[Ni0.2Cu0.3Co0.5Fe2O4] + (1-x)[Ba0.7Sr0.3TiO3] Composites

M E Composites with composition x[Ni0.2 Cu0.3 CO0.5 Fe2 O4 ] + (1-x)[Ba0.7Sr0.3TiO3 ], Where x varying from 0.1 to 0.4 in molar ratio, were prepared by standard double sintering ceramic technique. The presence of ferrites phase, namely [Ni0.2 Cu0.3 CO0.5 Fe2 O4 ] and ferroelectric phase, namely [Ba0.7Sr0.3TiO3 ], were confirmed by X-Ray Diffraction analysis, whereas SEM micrographs were obtained to study the morphology of samples. The x ray diffraction patterns exhibit a set of well-defined ferrites and ferroelectric peaks. The tetragonality ratio c/a, of the ferroelectric phase remains the same in all the samples, the porosity varies from 20% to30% while the average grain diameter lies in the range of 0.5µm to 2 µm.

The pre-coated photocatalytic ceramic membrane with Bi2O3–TiO2/powdered activated carbon nanoparticles to alleviate ultrafiltration fouling caused by intracellular organic matter of Microcystis aeruginosa

Algal intracellular organic matter (IOM), released during algae's normal growth phase and water treatment processes, has long been a source of significant membrane fouling, considerably limiting the effective use of ultrafiltration(UF) technology. In this study, a Bi-doped TiO2 composite with powdered activated carbon (Bi2O3–TiO2/PAC) was loaded on ceramic UF membranes by vacuum filtration, and the prepared photocatalytic modified ceramic membranes (MCMs) were investigated for the removal of IOM and the mitigation of membrane fouling at different loading levels and under three operating conditions: Dark, Dark-UV, and UV. The results showed that the photocatalytic MCMs were able to remove the protein and humic acid fluorescent components of IOM and decompose or mineralize organic matter with molecular weights of 10–50 kDa. Under the Dark, Dark-UV, and UV conditions, the final normalized flux of MCM-2.88 was significantly increased by 22.6 %, 82.1 %, and 108.0 %, respectively. The hydrophilicity of MCMs not only transformed the interactions between IOM and the membrane into repulsive forces, but also the composite material on the membrane surface transforms the membrane fouling mechanism from intermediate blocking model to cake layer formation. Furthermore, the application of photocatalytic oxidation under the Dark-UV and UV conditions yielded a reduction in both reversible and irreversible fouling. This action led to an increased hydrophilicity and elevated free energy of adhesion with IOM during the filtration process. Moreover, the main fouling mechanism changed into complete or intermediate blocking. These outcomes collectively underscore the capability of MCMs to alleviate membrane fouling induced by IOM. This advancement holds substantial promise for the advancement and widespread implementation of photocatalytic ceramic membrane filtration techniques.

Crosslinking and pyrolysis of a methyl-silsesquioxane: Effect of heating rate on fabrication of polymer derived mullite ceramics using thermoplastic shaping

Poly-silsesquioxanes have been numerously used to produce SiO2 or SixOyCz ceramics through pyrolysis under different atmospheres. In this study, crosslinking and pyrolysis behavior of a commercial methyl-silsesquioxane, was examined using thermogravimetry analysis and a lower SiO2 yield was observed after pyrolysis at low heating rates of 0.3 and 0.6 K/min under air atmosphere, namely 69.1 and 75.0 wt%, respectively. Using ceramic thermoplastic shaping techniques, a low heating rate, below 2 K/min, is usually required to remove processing additive (e.g., binders) gradually and avoid failures like blisters, pores, and cracks. A mixture of SILRES® MK and γ-Al2O3 was prepared to produce a mullite ceramic with Al2O3/ SiO2 ratio of 60/40 wt%. As expected, the stoichiometric ratio of alumina to silica was altered using a heating rate of 0.6 K/min and mullite ceramic with 61.70/37.70 wt% of Al2O3/ SiO2 ratio was obtained. By mixing above the crosslinking temperature of SILRES® MK, a constant ratio of alumina to silica could be achieved successfully, even at low heating rates. In addition, microstructure indicated the growth of needle-like mullite crystals with some amount of SiO2-rich ternary amorphous phase (MgO–Al2O3–SiO2) between the needle grains. Elemental analysis revealed that MgO sintering additive was mainly in the amorphous SiO2-rich phase.

Composition of technical ceramics of low-temperature sintering for grinding bodies

Optimal material and charge compositions of technical ceramics for grinding media have been developed. It has been established that the best indicators of the material composition and technological properties have prototypes of ceramic masses with alumina content from 55,25 to 64,93 wt. % for obtaining mullite ceramics, as well as 65,79 to 74,21 wt. % for obtaining mullite-corundum ceramics. The possibilities of using kaolins of various grades for the development of new compositions of grinding media for low-temperature sintering are shown.

Research on the Discrepancy and blending of Lacquer Ceramic Art

The rich historical use of lacquer in China and the enduring tradition of Oriental pottery have laid the foundation for preserving traditional handicrafts. This research seeks to uncover the cultural significance of lacquer items and innovative pottery, delving into their artistic elements to preserve their cultural essence. By examining the interaction between lacquer and pottery within an artistic framework and exploring the expert fusion of lacquer craftsmanship, this study provides valuable insights to foster the contemporary growth of traditional craft design. The research findings demonstrate that a precise integration of design elements inspired by the aesthetic qualities of lacquer artifacts into lacquer products effectively conveys cultural heritage in the present era. The design process for creative products evolves through the innovative amalgamation of lacquer and ceramic techniques, resulting in the creation of unique lacquer and ceramic pieces. The primary goal of this study is to inspire emerging designers to contribute to the ongoing innovative development of lacquer pottery products.

Machine learning-based design for additive manufacturing in biomedical engineering

While ceramic additive manufacturing (AM) technologies have shown great promise to create functional scaffolds with tailored biomechanical properties, the true potential of these advanced techniques has not been fully exploited yet due to lack of practical design optimisation approaches. To address this challenge, a machine learning (ML)-based design approach is proposed herein where ceramic 3D printing techniques are combined to fabricate functionally graded tissue scaffolds composed of Triply Periodic Minimal Surfaces (TPMS), aiming to fulfil the anticipated biomechanical requirements for the target bone regeneration outcomes. The proposed ML based design strategy couples a Bayesian optimisation (BO) algorithm to enable time-dependent mechano-biological optimisation of the 3D printed ceramic scaffolds at a reasonably low computational cost. For a representative example relating to bone scaffolding in a segmental defect of sheep tibia, the simulated results demonstrate that the optimised functionally graded scaffolds significantly enhance bone ingrowth outcomes. Furthermore, a Lithography-based Ceramic Manufacturing (LCM) technique is employed to fabricate the optimised scaffolds based on the proposed ML-based design framework, followed by micro-CT analyses of the additively manufactured ceramic scaffolds to assess their geometric qualities. This study is expected to gain new insights into mechanical sciences on design for varying material conditions and provide an effective design tool for ceramic additive manufacturing.

Reducing High Temperature System Development Cycle Time and Cost with Additively Manufactured Connectors

Connectors are a fundamental part of Ozark IC’s high temperature modules from characterization and test packages to Ozark IC’s XNode® data acquisition and single-board computing modules. Development of rugged high temperature electronic systems requires the co-development of similarly rugged high temperature connectors. The design and development of connector solutions enable test and evaluation of high temperature systems which would otherwise require fulfillment of a commercial connector order. There is a nascent supply chain of rugged, high temperature-rated connector designs but manufacturer lead times for such commercial products can exceed an entire design, prototype, and test cycle. Such delays are incompatible with rapid design iterations and fail-fast strategies employed in the development of extreme environment electronics – especially when the design and test cycles can change the requirements or specifications of the connectors. Polymer and ceramic additive manufacturing techniques enable in-house connector fabrication and support a connector co-development cycle that complements the pace and interdependent requirements of high temperature system development. These solutions are simple and reliable under laboratory conditions, operating for thousands of hours at 200 °C [1] and hundreds of hours at 800 °C [2]. The use of proprietary connectors manufactured with additive techniques and digital tooling lends an extra degree of freedom to system design and enables the trade-off of connector with system design specifications that greatly accelerates system ruggedization. Electrical connectors represent the final interface between an electronics module and the outside world. A failure of a connector is a failure of packaging that makes the module opaque to the tester and renders the power and robustness of any electronic system moot.

Delamination mitigation in additively manufactured Al2O3 via enhanced thermal postprocessing

AbstractManufacturing thick (>10 mm) alumina (Al2O3) parts through the ceramic additive manufacturing technique of digital light processing (DLP) is difficult due to the large amount of polymer that must be removed. Nearly 35–65 vol% of a fugitive UV‐curable polymer is used in commercial ceramic slurries in order to maintain shape through the DLP process. During the thermal debind, gases form and escape quickly due to pressure build‐up, leading to defects in the form of print layer delamination. Here, we analyze the polymer decomposition through thermogravimetric analysis in order to design a less aggressive thermal debind schedule through strategic thermal holds and decreased heating rates. The new schedule led to a 83% reduction in average delaminations per sample (from 6.9 delaminations per sample to 1.2 delaminations per sample) and up to a 100% increase in wall thickness (from nominally 10–20 mm). A complex, Al2O3 turbine rotor (with maximum wall thickness of 5 mm in the center hub section) of a JetCat P400 engine was fabricated to compare the new schedule to the manufacturer provided one. The improved thermal debind schedule produced a turbine rotor with no observable delamination defects.

Comparison of different 3Y-TZP substrates for the manufacture of all-ceramic micro end mills with respect to the cutting edge radius and the tool wear

In micro milling, size effects such as the ratio of uncut chip thickness to cutting edge radius result to high mechanical stresses. The tools need to be able to withstand these, with as little tool wear as possible. Cemented carbides are currently the tool substrates of choice. Technical ceramics are highly wear resistant as well, but they are not yet used in micro milling. To utilize their potential in micro cutting processes, we previously identified Y-TZP as the best ceramic for this purpose. Compared to cemented carbide, they exhibit only marginal tool wear when micro milling PMMA.To investigate whether the 3Y-TZP characteristics influence the performance of all-ceramic micro end mills, three different substrate materials were used to manufacture tools that were tested by micro milling of PMMA. Further varied factors were the feed per tooth and the spindle speed. The initial cutting edge sharpness of the tools and the tool wear were used to quantify the results. One substrate was found to result in lower cutting edge radii and a more stable manufacturing process than the others. Also, a feed per tooth dependent wear behavior was observed.

Interface adhesion on layered zirconia: Effects of the veneering ceramic material and veneering technique.

To evaluate the effect of different veneering ceramics and veneering techniques on the bond strength to zirconia. 3Y-TZP zirconia blocks were sliced into 60 slabs, polished, and sintered. Each slab received one ceramic cylinder (Ø = 3.4mm, 5mm-high), according to the veneering ceramic type (feldspathic-FEL or lithium disilicate-based-LD) and the veneering technique (file-splitting with resin-based luting agent-RC, file-splitting with fusion ceramic-FC, or heat-pressing-HT), which resulted in six groups: FEL-RC, FEL-FC, FEL-HT, LD-RC, LD-FC, LD-HT. After preparation, the samples were immersed in distilled water for 24h before the shear bond strength (SBS) test. The failure modes were classified as adhesive, predominantly adhesive, or cohesive. Representative failure mode images were taken in a Scanning Electron Microscope. The SBS data were analyzed by two-way ANOVA and Tukey's test. Both type of veneering ceramic and technique affected the bond strength. FC led to the highest SBS values. RC and HP provided similar results when compared within each veneering ceramic. Lithium disilicate achieved lower bond strength than feldspathic ceramic when the heat-pressing technique was applied. The most frequent failure modes were predominantly adhesive and adhesive for FEL and LD, respectively. File-splitting with fusion ceramic provided the highest adhesion to zirconia when feldspathic or lithium disilicate-based ceramics were used. The heat-pressing technique for veneering with lithium disilicate significantly decreased the bond strength when compared to the feldspathic ceramic.

About the problems and results of obtaining products from technical ceramics for metallurgical production. Message 2

The article presents the results of research in the field of synthesis of multifunctional ceramic materials for metallurgical, machine‑tool and other industries related to the processing of metals, their alloys and products from them; current trends and trends associated with the production of products from such materials; provides information on expanding the domestic raw material base for the production of ceramics with the involvement of domestic enterprises, and also, the prospects for the development of industrial potential for the organization of the production of such products.