Firing Temperature Research Articles

Pelatihan Pembuatan Kit Praktikum Fisika Berbasis Mikrokontroler Arduino Uno di SMK Negeri 9 Muaro Jambi

Arduino uno microcontroller is an open source based integrated circuit device that can be easily obtained, relatively cheap, accessible, and low power consumption. It can be applied to design practicum kits related to electronics and electricity. Our community service activity was holding a workshop on making practicum kits based on the Arduino Uno microcontroller for teachers at SMK Negeri 9 Muaro Jambi. The program was carried out through three stages, firstly, observation and survey, next was planning and preparation, and the last one was training. The themes of the chosen practicum kits were the LED turning-on program, distance measuring program, fire detection program, and temperature and humidity measurement. Each of the kits was equipped with the sets needed for practicum, such as Arduino Uno, jumper cables, LEDs, breadboard/protoboard, resistors, USB cables, sensors, etc. The practicum guide book contained the objectives of the practicum, tools and materials used, programming language commands to be uploaded, as well as work steps and evaluations. Workshop was carried out by a lecture about arduino uno microcontroller and demonstration of how to operate practicum kits. During the demonstration activity, the teachers were enthusiastically discussed and asked questions about Arduino Uno microcontroller as a practicum kit.

Ceramic Firing Temperature Trajectory Monitoring System on IoT-Based Gas Furnace

This study introduces a novel system where a conventional ceramic furnace is upgraded with IoT capabilities, specifically utilizing NodeMCU and a thermocouple sensor. The integrated system enables real-time temperature monitoring, facilitating the correction of firing trajectory errors in the ceramic firing process. The sensors reading minimizes errors by detecting temperature changes with a maximum deviation of -2.5 °C and a minimum deviation of -1 °C. The average error ranges from 1.81% to 3.79%. The collected data is seamlessly transmitted to Google Spreadsheet for online monitoring. This comprehensive solution not only minimizes recording errors but also ensures the quality of final ceramic products by preventing issues such as cracks, breaks, black cores, and non-uniform sizes. The incorporation of NodeMCU, thermocouple sensors, and online monitoring represents a significant technological leap in optimizing ceramic firing processes for heightened precision and efficiency.

Examining the properties, behaviour in firing and potential application of coal mine overburden for stoneware ceramics

Purpose. A binary mixture of a ceramic body was studied, incorporating overburden from a coal mine site in Bontang, East Kalimantan, Indonesia. This overburden material has been tested for the manufacture of stone-ceramic body. Methods. The initial characterization of overburden materials includes testing the chemical composition by XRF analysis and mineral content by XRD analysis on raw materials and overburden exposed to high temperature. The composition of ceramic specimens is a mixture of 85% overburden material and 15% fine sand. Firing temperatures in the range of 900-1100°C were applied to the ceramic body specimen. Then, ceramic properties, such as physical color, plasticity, shrinkage, water absorption and density were analyzed. Findings. The results show that the ceramic specimen experiences densification when exposed to high temperature in this range, which in turn contributes to low water absorption and high flexural strength. This ultimately results in low water absorption below 1.0% at 1100°C, which is favorable for stoneware type of ceramics. The mechanical properties of specimen at 1000°C is in accordance with stoneware body standard. In addition to this, it is believed to be more energy efficient, since the low firing temperature is sufficient to achieve the stoneware specification. Originality. The binary clay-based ceramic have been tested using coal mine overburden and river sand with a high Fe2O3 content. Together with the presence of alkali oxides and calcium in the raw materials, this can potentially reduce the use of fluxing agent. A comprehensive study has been conducted on the characteristics, firing effect and application of stoneware. Practical implications. Some ceramic prototypes from this result were also made using a rotary technique and heated in this temperature range. Since overburden is generally considered to be backfill material, the selective clay material application for ceramics can provide the potential to stimulate local product innovation by utilizing easily available overburden materials.

ОСОБЕННОСТИ ТЕХНОЛОГИИ ИЗГОТОВЛЕНИЯ КЕРАМИКИ НАВЕСА МЕШОКО

The article describes the findings of a petrographic research of the Meshoko shelter’s ceramics. A total of 32 fragments were studied, 22 fragments – from the 5th (Chalcolithic) layer, 10 fragments – from the upper part of the 6th layer (layer 6a). Based on the analysis, 4 groups of ceramics were identified. Group 1 consists of fragments with admixture of limestone, group 2 – with admixture of limestone and intrusive rocks, group 3 – with admixture of limestone and metamorphic rocks, group 4 – with admixture of intrusive rocks. The types of clays were also determined, among which lean clays of smectite and smectite-chlorite composition predominate. Based on the types of clays, firing options and admixture within the groups, subgroups were identified. Ceramics of all the selected groups are found in both the 5th and 6th layers, but their subgroups completely distinguish. This ceramics also differ in the duration of firing and the nature of surface treatment. The results of the ceramics study of the Meshoko shelter’s 5th and 6th strata were also compared with the results of the Meshoko settlement’s ceramics analysis. The ceramics of its lower layer turned out to differ completely from the ceramics of the shelter. But the upper part of the settle-ment deposits with a shelter is united by the presence of ceramics with an admixture of limestone. However, there are also differences in the temperature and duration of firing, the nature of surface treatment. The data obtained indicate a significant diversity of ceramic traditions in the Chalco-lithic of the Belaya River basin, which may also indicate a complex composition of the popula-tion.

ИНСТРУМЕНТАРИЙ ОПЕРАЦИОННОЙ ПОДДЕРЖКИ В ОЦЕНКЕ ИНТЕНСИВНОСТИ ТЕПЛОВОГО ИЗЛУЧЕНИЯ ПРИ ПОЖАРЕ В ЗДАНИИ УВЕЛИЧЕННОЙ ОКОННОЙ ПРОЕМНОСТИ

It is shown that the task of taking into account the impact of thermal radiation from a fire for determining safe distances for situating fire engines and choosing positions for firefighters during developing operational fire extinguishing plans for industrial buildings with enlarged window openings is not fully supported by the functionality of existing software systems. Since thermal radiation as one of the components of dangerous fire factors valuable only with a sufficient exposure, we analyze events tree branches associated with the process of diffusion combustion on the surface of a flammable liquid spill. Algorithms of the fire temperature regime module in the room of an industrial building with an enlarged window opening are presented based on an integral model and the module of the directional pattern of thermal radiation through window openings. The results of numerical modeling using the presented software product allow us to conclude that the effect of thermal radiation diaphragmization by window openings weakens with distance from the front of the heat-emitting surface and becomes negligible at distances of five meters and more.

THE INTERACTION BETWEEN A WHITE MATERIAL INSIDE AND OUTSIDE A POTTERY VESSEL FROM EASTERN EIN-SHAMS, EGYPT

This work aims to investigate a pottery vessel from eastern EIN-Shams, Egypt, lying in sandy soil from citizen lands, returning to the New Kingdom-Egypt. This pottery vessel was covered with white material from inside and outside. In terms of origin, this vessel is made of buff-colored clay; it has big pores, many cracks, and large missing areas filled with that material, with an uneven surface texture, that strongly bonds with the body pores, and shrinks away from the edges in some areas, in this way obscuring the original surface. In this respect, several physicochemical investigations in terms of chemical composition, physical properties, and nature of this white material were performed, to analyze the influence of it on the ancient pottery vessel. The analytical methods used in this research were USB digital microscopy, X-ray diffraction (XRD), scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX), and differential thermal analysis (DTA). The results of the USB digital microscopy showed the presence of gypsum crystals, large, flaked pottery surfaces, and quartz. SEM-EDX revealed the presence of organic fibers, chloride salts in a significant percentage, iron, and aluminum oxides. XRD investigation emphasizes the presence of gypsum and sodium chloride salts. DTA results revealed that the firing temperatures of the pottery vessel range between around 750-800°C.

Effect of Ceramic Thickness and Technician Variability on the Shade Duplication of Dental Ceramo-Metallic Restorations.

Ceramic thickness and technicians' manipulative variables are critical factors affecting the resultant shade of dental ceramo-metallic restorations. This study investigated the effect of the following variables on shade duplication of ceramo-metallic specimens: (a) ceramic thickness; (b) differences between several technicians (inter-technician variability); and (c) the ability of each technician to repeat the resultant shade (intra-technician variability). Ninety ceramo-metallic specimens were prepared and divided into three main groups (n = 30/gp) according to the different technicians who built up the veneering ceramic of the specimens. Each group was further subdivided into three subgroups (n = 10/subgroup) according to the thickness of the ceramic (1, 1.5, and 2 mm built over a 0.5 mm-thick metal substructure). Three different technicians were asked to follow the same protocol as regards the same ceramic batch (Shade 3M2, Vita VM13, Zahnfabrik, Germany), firing temperature, and number of firing cycles. Meanwhile, each technician followed his own protocol with regard to other ceramic manipulative variables. The duplicated shades of the specimens were investigated using the Vita Easyshade spectrophotometer by using the verify shade mode. Color difference (∆E) values were calculated between the target shade (3M2) and the duplicated shades of the specimens automatically by the Vita Easyshade spectrophotometer (Vita, Zahnfabrik, Germany). The effect of ceramic thickness and inter- and intra-technician variability on the duplication of the target shade was investigated. The results showed that the effect of ceramic thickness on the duplicated shades depended on inter-technician variability. High inter-technician variability (∆E = 2-6.4) was noticed in contrast to low intra-technician variability (∆E = 0.2-1.5). It could be concluded that proper shade-duplication of ceramo-metallic restoration was a cumulative technique intimately related to manipulative variables and ceramic thickness.

Study of the influence of mineralizer and firing mode on the properties of slavsonite­celsian ceramics

The effect of 0.7 % (more than 100 % of the batch) of a low­melting mineralizer (eutectic mixture of Li2O and SnO2 with a melting point of about 650 °C), as well as temperatures of 1350, 1400, and 1450 °C and holding time at the maximum temperature (2—6 hours) on the properties of slavsonite­celsian ceramics with a slavsonite : celsian ratio of 3 : 1 in comparison with the properties of the same ceramics without mineralizer, fired at 1250, 1350, and 1400 °C with a holding time at a maximum temperature of 2 hours, was studied.
 It was found that the mineralizer used in the amount of 0.7 % significantly inhibits the sintering of slavsonite­celsian ceramics with a slavsonite : celsian ratio of 3: 1. As a result, the obtained values of water absorption (10.2 and 8.18 %) and open porosity (22.93 and 19.9 %) of the samples with the mineralizer, fired at temperatures of 1350 and 1400 °C and a holding time of 2 hours, are almost 2 times higher (i.e., worse) than those without the mineralizer (5.8 and 4.7 %, and 14.7 and 12.0 %, respectively). Therefore, an introduction of the mineralizer (eutectic mixture of Li2O and SnO2) in the amount of 0.7 % into slavsonite­celsian ceramics with a slavsonite : celsian ratio of 3 : 1 is impractical under these conditions.
 Firing temperature in the range of 1350—1450 °C and holding time in the range of 2—6 hours have virtually no effect on the strength of samples with the mineralizer addition (eutectic mixture of Li2O and SnO2) in the amount of 0.7 %.

Fabrication of V1−x Ti x O2 microbolometers on Si3N4/SiO2 membranes

V1−x Ti x O2 thin films have been prepared on Si3N4/SiO2/Si substrates by the two-step process of (1) growth of VO2/TiO2 thin films by metal-organic decomposition with carbothermal reduction, and (2) the interdiffusion between V and Ti atoms at the interface between the VO2 and TiO2 thin films during the growth of the VO2 thin film. The abrupt resistance change and the thermal hysteresis due to the metal-insulator transition were gradually suppressed with increasing the firing temperature, and they completely disappeared for the V0.65Ti0.35O2 thin film prepared at 650 °C. A relatively high TCR of −4.2%/K was obtained from the film over a wide temperature range of 20 °C–90 °C. V0.65Ti0.35O2 microbolometers with a size of 5 μm × 15 μm were fabricated by photolithography and Ar ion milling, and a Si3N4/SiO2 membrane under the microbolometer was formed with an aqueous KOH solution. The DC sensitivity of the fabricated microbolometer on the membrane was estimated to be 9876 W−1 and 20 times higher than that of the microbolometer on the Si3N4/SiO2/Si substrate. The V0.65Ti0.35O2 microbolometer on the membrane is available for a terahertz detector operating over the wide temperature range.

One-Dimensional La0.2Sr0.8Cu0.4Co0.6O3-δ Nanostructures for Efficient Oxygen Evolution Reaction.

Producing oxygen and hydrogen via the electrolysis of water has the advantages of a simple operation, high efficiency, and environmental friendliness, making it the most promising hydrogen production method. In this study, La0.2Sr0.8Cu0.4Co0.6O3-δ (LSCC) nanofibers were prepared by electrospinning to utilize non-noble perovskite oxides instead of noble metal catalysts for the oxygen evolution reaction, and the performance and electrochemical properties of LSCC nanofibers synthesized at different firing temperatures were evaluated. In an alkaline environment (pH = 14, 6 M KOH), the nanofibers calcined at 650 °C showed an overpotential of 209 mV at a current density of 10 mA cm-2 as well as good long-term stability. Therefore, the prepared LSCC-650 NF catalyst shows excellent potential for electrocatalytic oxygen evolution.

Use of recycled carbon fibre as an additive in the manufacture of porous bricks more durable against salt crystallization

Within the framework of the Sustainable Development Goals of the Agenda 2030, the circular economy is being promoted as a means of ensuring a sustainable use of resources and a reduction in the amount of waste produced. The aim is to reduce the demand for often scarce raw materials through the continuous reuse, recycling and regeneration of materials and products. This paper explores the use of carbon fibre from wind turbine blades as an additive in the production of new efficient bricks. Clay mixes with 0, 5 and 10 wt% additive were fired at three temperatures (800, 950 and 1100 °C) and the fired bricks were analysed from mineralogical and physical points of view to determine their suitability for use in the construction industry. The results show that carbon fibre improves the durability of the bricks, which became 16 % more porous as the firing temperature increased. However, the compressive strength of the bricks with 10 wt% carbon fibre was about 50 % lower than that of the control bricks made without additive. It is interesting to note that the distribution of the carbon fibres within the brick varies considerably and that they are shorter and wider in the core of the samples. These results could offer an alternative line for new product development in the brick industry. The bricks tested here are an example of a circular economy in which waste from one industrial process (wind turbine blades) is reused as an input in another (brick manufacture). The environmental benefits achieved are twofold: reduced demand for clay and recycling of decommissioned turbine blades, which are currently amassed in wind turbine graveyards.

Enhancing the sustainable production of cost-effective ceramics with high strength using kaolin, sewage sludge and blast-furnace slag

Solid waste treatment remains an unavoidable environmental burden for modern cities. Currently, the multipurpose utilization of solid waste in construction and building materials is worth in-depth research as it furnishes high-value commercialization pathways with environmental and economic benefits for managing waste and addressing resource scarcity. This study explored the cost-effective ceramic fabrication from 40 % sewage sludge, 10 % blast-furnace slag and 50 % kaolin through in-situ sintering method, which enhanced the sustainable production of ceramic materials. The influences of firing temperature on the ceramic sintering effects, including mineral composition, micromorphology, pore structure and process performance, were systematically investigated. Results showed that the particle consolidation and sintering degrees of finished ceramics continuously increased as the firing temperature raised, presenting different surface, cross-sectional and pore structure characteristics. This was because increasing the firing temperature changed natures of the formed glass phase, such as content and viscosity. Moreover, variations in the ceramic structure would further affect its process performance. The ceramics prepared at 1250 °C were determined to have best firing effects with the densest structure and excellent performance, and the corresponding water absorption, bulk density, apparent porosity and compressive strength were 0.97 %, 2.32 g/cm3, 2 % and 70 MPa, respectively. Finally, comparisons with other researches confirmed that the developed ceramics possessed strong competitiveness in process performance. The presented study provided data support for the value-added application and sintering optimization of waste slag and sludge in ceramic production.

Realtime Monitoring and Analysis Based on Cloud Computing Internet of Things (CC-IoT) Technology in Detecting Forest and Land Fires in Riau Province

Forest and land fires in Riau are natural disasters that always repeat every time they enter the dry season. The solution of this research is to apply the leading technology of cloud computing internet of things (CC-IoT) to find out more quickly the existence of forest or land fires. This study uses Particle Argon (Photon) to connect to the internet and several IR Fire Detector sensors, DHT22 MQ2 and GPS Neo 6m. Particle Argon can receive input and perform processing so that it is connected using the CC-IoT concept to a web server so the users can monitor land conditions in real time. Based on the test results, it can be concluded that a fire detector using fire parameters (2000 = Normal and 2000 = Danger) , temperature (≤37 = Normal, 38 – 45 = Alert, and 46 = Danger), humidity (≤50 = Dry, 51 = Humid) , smoke (≤ 1700 = Normal, 1700 = Danger), and soil moisture can work well ( 3500 = Dry Moisture Content, 1500 to 3500 = Medium Moisture Content, and 1500 = High Moisture Content). The fire detection tool developed can detect fires in real time and also has a fire early detection function that is useful for anticipating land conditions to prevent fires. The results obtained from the test are that the sensor can read indications of fire, smoke, soil moisture with a success rate of 93% and send location data and sensor values to the website. The use of sensors has their respective roles so that if there is a problem with one of the sensors, the tool has an alternative sensor and can continue to function.

Charcoal morphologies and morphometrics of a Eurasian grass-dominated system for robust interpretation of past fuel and fire type

Abstract. Recent developments in morphological and morphometric analyses of charcoal particles have improved our ability to discern characteristics of burnt plant fuel and interpret fire-type changes. However, burning experiments linking known plants to these metrics are limited, particularly in open ecosystems. This study presents novel analyses of laboratory-produced charcoal of 22 plant species from the steppe regions of Eurasia (Romania and Russia), along with selected samples from three Holocene charcoal and pollen records from the same areas. We characterise charcoal production, morphologies and morphometrics in these grass-dominated environments, thereby enabling more robust interpretations of fuel sources and fire types for palaeofire research. Our experiments demonstrate that fire temperature can introduce biases in charcoal produced among species. Grass charcoal production was significantly lower and decreased more strongly with fire temperature compared to forbs. This suggests an underrepresentation of terrestrial graminoids in sedimentary charcoal assemblages. Morphometric analyses revealed that graminoid charcoal particles were more elongated (length-to-width ratio L/W=4) and narrower (width-to-length ratio W/L=0.38) than forbs (L/W=3.1 and W/L=0.42, respectively), in agreement with a global compilation for graminoids (L/W=4.3 for grass 5.4 grass and wetland graminoids) and forbs (L/W=2.9). However, overlapping L/W values present a challenge for establishing cut-off values for fuel type identification in charcoal assemblages with mixed fuel sources. Based on our analyses and compiled datasets from experimental burns, L/W values above 3.0 may indicate predominantly herbaceous morphologies in temperate grassland-dominated ecosystems, though values are likely to be higher for grass than forb-dominated grasslands. Notably, terrestrial grasses exhibit shorter aspect ratios (L/W=4.3) than wetland graminoids (L/W=6.4), highlighting that the aspect ratio needs tailoring to the specific environment of its application, i.e. wetland vs. terrestrial ecosystems. The long forms of graminoid charcoal particles also suggest their potential for atmospheric longer-distance transport compared to more spherical particles, meaning they likely provide insights into regional fire history. An important finding is that charcoal of herbaceous plants closely corresponded to the pollen record, highlighting a solid link between the dominant vegetation and fuel burnt in grassland-dominated environments. However, the relationship between woody charcoal and tree pollen may be more complex, as tree pollen can travel atmospherically longer distances compared to woody charcoal. Our results also highlight the complex interplay between local vegetation and charcoal composition with human fire use that needs to be considered when interpreting charcoal morphological records. A critical takeaway from this study is the importance of not assuming the universality of previous research findings and instead employing experimental approaches to characterise charcoal particles in new ecosystems prior to the application of these techniques. Furthermore, this study also highlights recommendations for further research in new geographical areas and proposes methodological adjustments to enhance the usefulness of charcoal analysis in fire research.

Thermodynamic simulations for optimizing the firing of traditional ceramic formulations using waste glass as a flux

The complex chemical reactions that occur between raw materials during the firing of traditional ceramics are still not fully understood, and no tool can accurately simulate what happens in this process. Thermodynamic data calculations, based on the minimization of the free energy of the system, have been used to deduce the nature of the phases (solid/liquid), the chemical composition and its viscosity, and to better understand the phenomena and reactions that occur in equilibrium conditions at elevated temperatures. In this work, quantifications of phases predicted through chemical thermodynamic simulations and experimental quantifications of the phases of ceramic formulations with the use of alternative flux (waste glass) sintered at 1200 °C are presented, in addition to the viscosity of a formulation with the integral replacement of the fluxing raw material from soda-lime glass waste. The data presented show that the use of the FactSage software can help in the study of raw material transformations and in determining the firing temperatures of ceramic materials, contributing to studies in which fluxing raw materials are replaced, partially or fully, by other sources. The thermodynamic study, despite some limitations, contributes to the optimization of a formulation for recycling industrial waste into ceramic materials.

Mechanical properties and strengthening mechanism of SiC particle reinforced porcelain

AbstractMechanical properties of porcelain based on feldspar porcelain as a matrix with SiC particles as a reinforcing phase were studied in terms of the effects of SiC content, firing temperature, and holding time. A maximum flexural strength of 122 ± 4 MPa was achieved for a sample with 8 wt% SiC content treated at 1260°C for 30 min, which is 90.6% as high as than that of the unmodified matrix (64 ± 5 MPa). The fracture toughness and elastic modulus of the former sample were 1.71 MPa · m1/2 and 89.975 GPa, respectively. Because the thermal expansion coefficient of SiC (4.40 × 10−6/°C) is smaller than that of the glass phase (6.60 × 10−6/°C), the SiC particles remain in a state of compressive stress after the porcelain cooling. This characteristic restricts crack growth and offsets the tensile stress of the glass phase, restraining crystal growth owing to the tensile stress pinning the grains, such that the mechanical properties are improved.

Experiment study on the mechanical properties and constitutive model of grade 1960 steel wires under and after elevated temperatures

To investigate the effects of different temperatures and cooling patterns on the surface characteristics, failure modes and mechanical properties of steel wires, a total of 52 steel wires of grade 1960 under and after elevated temperatures were tested. Then, the influence mechanism of temperatures on mechanical properties was further revealed with the help of SEM fracture scanning. Furthermore, the laws of reduction coefficient of mechanical properties of steel wires under and after elevated temperatures were proposed. Finally, the equation of high temperature stress-strain curve of steel wires was constructed. The results showed that the surface colors of steel wires gradually deepened with the increase of temperature, and a mass of zinc oxide particles appeared on the surface of steel wires at 500 °C, when the galvanized layer began shedding a lot. Meanwhile, the fracture shape of the specimens became obvious cup-cone, especially when the temperature exceeded 600 °C, the shape turned conical. In addition, the elastic modulus, yield strength and tensile strength of steel wires at 300 °C accounted for 85 %, 68 % and 74 % of the corresponding mechanical properties at room temperature, respectively. When the temperature exceeded 300 °C, the mechanical properties of steel wires would decrease significantly. For example, the ultimate strength of steel wire at 400 °C was only 53 % of that at room temperature. Nevertheless, the mechanical properties of steel wires after high temperature were basically unchanged before 300 °C. Similarly, the mechanical properties of steel wires gradually decreased after cooling by temperature action above 300 °C. For example, when the heating temperature was 600 °C, the ultimate strength was only 46 % of that at room temperature. Ultimately, comparing with the result of experimental and previous literature, the accuracy of the proposed formula for the reduction coefficient of high temperature mechanical properties and constitutive model of steel wire was verified. It is recommended to set the fire resistance temperature of steel wire inside the bridge cable at around 300 °C.

SrTiO3-SrVO3 Ceramics for Solid Oxide Fuel Cell Anodes: A Route from Oxidized Precursors.

Perovskite-type Sr(Ti,V)O3-δ ceramics are promising anode materials for natural gas- and biogas-fueled solid oxide fuel cells, but the instability of these phases under oxidizing conditions complicates their practical application. The present work explores approaches to the fabrication of strontium titanate-vanadate electrodes from oxidized precursors. Porous ceramics with the nominal composition SrTi1-yVyOz (y = 0.1-0.3) were prepared in air via a solid state reaction route. Thermal processing at temperatures not exceeding 1100 °C yielded composite ceramics comprising perovskite-type SrTiO3, pyrovanadate Sr2V2O7 and orthovanadate Sr3(VO4)2 phases, while increasing firing temperatures to 1250-1440 °C enabled the formation of SrTi1-yVyO3 perovskites. Vanadium was found to substitute into the titanium sublattice predominantly as V4+, even under oxidizing conditions at elevated temperatures. Both perovskite and composite oxidized ceramics exhibit moderate thermal expansion coefficients in air, 11.1-12.1 ppm/K at 30-1000 °C, and insignificant dimensional changes induced by reduction in a 10%H2-N2 atmosphere. The electrical conductivity of reduced perovskite samples remains comparatively low, ~10-1 S/cm at 900 °C, whereas the transformation of oxidized vanadate phases into high-conducting SrVO3-δ perovskites upon reduction results in enhancement in conductivity, which reaches ~3 S/cm at 900 °C in porous composite ceramics with nominal composition SrTi0.7V0.3Oz. The electrical performance of the composite is expected to be further improved by optimization of the processing route and microstructure to facilitate the reduction of the oxidized precursor and attain better percolation of the SrVO3 phase.

Assessing the Effects of Refuse-Derived Fuel (RDF) Incorporation on the Extrusion and Drying Behavior of Brick Mixtures

This study explores the potential benefits of incorporating Recycled Demolition Waste (RDF) as an additive in ceramic mass for the brick industry, with a focus on applications such as thermoblocks. The research underscores the significance of sustainable waste management practices and environmental conservation by diverting waste from landfills. RDF, exhibiting combustion properties above 550 °C, emerges as a valuable candidate for enhancing clay-based materials, particularly in the brick production process where firing temperatures exceed 850 °C. Conducted in two phases, the research initially concentrated on RDF preparation, RDF integration with clay materials, and its influence on extrusion and drying phases. Employing innovative techniques involving brick and tile industry machinery coupled with sand incorporation yielded promising results. The grounding of RDF particles to less than 1 mm not only facilitated the mixing process but also ensured stable grinding temperatures within the hammer mill, reducing operational costs. During extrusion, challenges associated with unprocessed RDF material were addressed by utilizing ground RDF, leading to a more efficient and cost-effective process with enhanced plasticity and reduced water requirements. Practical implications for brick plant operations were identified, promoting resource and energy savings. Drying behavior analysis revealed the positive impact of RDF integration, showcasing reduced sensitivity, decreased drying linear shrinkage, and improved density properties. RDF’s role as an inert additive resulted in a 5% reduction in density, enhancing porosity and thermal insulation properties, particularly in thermoblock applications. In the brick industry, where durability, thermal performance, and cost-efficiency are paramount, this study emphasizes the potential benefits of incorporating RDF into clay-based materials. While further research is needed to address the firing procedure of RDF as a brick mass additive, the initial findings underscore the promise of this approach for sustainable and environmentally responsible brick production. This study contributes to the literature by shedding light on the advantages and challenges of integrating RDF into clay-based products, supporting sustainability and waste reduction in construction and manufacturing. The findings provide valuable insights into the performance and feasibility of these mixtures, offering crucial information for industries striving to adopt eco-conscious production methods. This article not only outlines the applied methodology and experimental setup but also presents results related to the behavior of RDF-inclusive clay block mixtures in the production environment. Anticipated to exert considerable influence on future practices and policies, this research contributes to the growing body of knowledge concerning eco-friendly and sustainable manufacturing processes.

PHYSICAL AND THERMAL CHARACTERISTICS OF EXPANDED FOAM GLASSES USING CRUDE GLYCEROL AS A FOAMING AGENT

Expanded foam glasses were fabricated from a clear color soda-lime silicate glass. Crude glycerol was used as an effective foaming agent which promoted small closed cell pores. This research studied the effect of crude glycerol content on the expanding characteristics and thermal properties. The expanding behavior relied on the thermal decomposition mechanism of the foaming agent as well as the sintereing temperature. Expanded foam glasses fabricated at 850°C showed uniform pore size compared to those fabricated at other temperatures (800°C and 900°C). Pore size of the synthesized foam glasses generally increased with increasing firing temperature. The evidence of black color in some areas for samples fabricated at 800°C occurred due to incomplete combustion of crude glycerol within the bulk structure. Samples produced at 850°C and 900°C showed white color shading associated with complete combustion of carbonaceous compound. Foam glasses sintered at 900°C showed structural distortion due to glass melting during the foaming process. Large holes or gaps within the structures occured due to the sweeping and combining of gas bubbles during sintering.