Effect of the firing temperature on the technical properties of clay ceramic added with blast furnace sludge waste

Effect of firing temperature on some physico-mechanical properties of ten brick samples, those were composed by feldspars, quartz, alumina-rich spinel, primary mullite and hematite phases, was investigated in accordance with ASTM standards. The brick samples fired between 700° to 1100° C showed 11-23 % water adsorptivity (WA), 19-37 % apparent porosity (AP) and 1.50-1.65 g/cm3 bulk density (BD) indicate good physical properties. The maximum compressive strength (CS) of the fired-bricks at 950° to 1000° C was found to be between 15.6 and 17.1 MPa. At 700°-1000° C firing temperatures, the CS of these bricks is found to be increased exponentially with decreasing of both WA and AP, however it is found to be increased with increasing the BD. Consequently, it can be said that there is good correlation between mechanical and physical properties of the fired-brick samples up to the firing temperature of 1000° C.
 Bangladesh J. Sci. Ind. Res.55(1), 43-52, 2020

It has been investigated the effect of firing temperature on water absorption and flexural strength in the manufacture of BL1P code stoneware ceramics. Ceramics are made in the form the test block bar with materials from of Borneo Clay Noodle, PRC Feldspar, Kaolin Belitung, Belitung Quartz, Ballclay Bantur, Bentonite, and Talk with a simple casting method. The block bar of the molds was burned at four temperature variations, i.e. 850, 900, 1000, and 1200 oC. From the results of measurements of it water absorption, it was found that the increase in firing temperature from 850 oC to 1200 oC showed a decrease in water absorption from 18.3% to 5.5%, while the measurement of it flexural strength showed an increase in flexural strength of 11.6 kg/cm2 to 19.8 kg/cm2.

Sintered wollastonite-plagioclase glass ceramics were prepared through crystallization of a parent glass generated by vitrification of pyrolysis residual glass fibers that had been pyrolytically recovered from waste composite materials. A vitrifiable mixture consisting of 95% by weight glass fiber and 5% by weight Na2O was melted at 1,450°C to obtain a glass frit. The glass-ceramic materials were produced by a sinter-crystallization process from the powdered glass frit. The effect of firing temperature on the properties of sintered-glass ceramics was investigated. The sintering behavior of glass-ceramic tiles was evaluated by means of water absorption, apparent porosity, and bulk density. In addition, the mineralogical and microstructural characterization of these tiles was carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results from experiments such as water absorption, bending strength, chemical resistance, and stain resistance have shown that the developed ...

A self-flowing low-cement bauxite castable was prepared from 64 wt.% rotary Chinese bauxite and 10 wt.% Eczacibasi calcined alumina aggregates with additives of 5 wt.% Lafarge cement Secar 71, 8 wt.% Elkem microsilica 971U, and 0.05 wt.% dispersant Darvan 7S (D7S). Optimum self-leveling flowability was achieved using 5.6% water addition. As a function of the firing temperature, the physicomechanical and refractory properties of the self-flowing low-cement bauxite castable were characterized in terms of densification parameters such as apparent porosity (AP), bulk density (BD), water absorption (WA), and cold crushing strength (CCS). Phase analysis and microstructural-based evaluation were performed using x-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The present bauxite-based refractory castable heat treated at 1500°C for 2 h exhibited the following properties: AP 13%, BD 2.93 g/cm3, WA 4.4%, and CCS 1365 kg/cm2.

Effect of firing temperature on the microstructure and performance of PrBaCo 2O 5+ δ cathodes on Sm 0.2Ce 0.8O 1.9 electrolytes fabricated by spray deposition-firing processes

This work studied the effects of firing temperatures on the refractory properties of insulating firebricks produced from a blend of hydrometallurgically purified clay, high alumina cement and sawdust. Twenty grams out of a bulk (1000 Kg) of clay obtained from Ipetumodu in Nigeria was analyzed for size range, consequent upon which the remaining bulk was sieved to 100 µm, being the average size. The bulk was there after leached under a predetermined condition (1.6 mol/dm3 of oxalic acid at 70˚C for 150 min and 200 rev/min agitation speed) and cylindrical samples (5 cm diameter by 5 cm high) containing different quantities of high alumina cement (5% - 20%) and sawdust (1% - 5%) were prepared, dried at 110˚C and subsequently fired at 900˚C, 1100˚C, 1300˚C and 1500˚C, at the rate of 4˚C/min and soaked for 2 hrs. These samples were subjected to different refractory tests (permanent linear change, modulus of rupture, bulk density, cold crushing str- ength and apparent porosity). Even though samples containing more than 20% alumina crumbled at elevated temperatures, it was still observed that the bricks performed to expectations at lower alumina contents, even at 1500˚C. The sample containing 3% sawdust and 10% alumina cement however, gave the desired requirement for preparing good insulating firebricks with reliable phase integrity, as revealed by scanning electron microscopy (SEM).

Porcelain balls as grinding media are produced by firing process of clay, quartz and feldspar mixtures. This application need high technological properties such as high compressive strength and hardness, wear resistance, low water absorption and excellent chemical resistance. These properties are associated with higher firing temperatures. The porcelain balls were prepared by mixing 30 wt.% clay, 40 wt.% feldspar and 30 wt.% quartz. The samples were sintered at 1200°C, 1230°C, 1250°C, 1270°C and 1300°C for 2 hours with heating rate of 3°C/min. Both green powder and fired samples were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM).The properties of the fired samples were evaluated by compressive strength, hardness, shrinkage, water absorption, bulk density, and porosity measurement. Increasing of compressive strength, hardness and density are associated with increasing of firing temperatures. Porcelain balls PB1 and PB2 can be produced as grinding media with optimum mechanical and physical properties at firing temperature 1270°C and 1250°C, respectively.

Effects of some processing factors on technical properties of a clay-based ceramic material

Effect of firing temperature on sintering of cordierite-mullite refractories from raw materials and Narathiwat clay in Thailand

Perovskite type complex oxide L0.8Sr0.2CoO3-δ symmetrical cells were prepared on Samaria doped ceria electrolyte Ce0.85Sm0.15O2-x by using the screen-printing method in a laboratory scale. The performance of the symmetrical cell was investigated by using electrochemical spectroscopy at frequency ranging from 0.1–300 kHz. Effect of firing temperature from 975–1,050 °C was investigated under the controlled oxygen pressure from 0.002–0.21 atm and controlled measuring temperature from 635–782 °C. The preliminary results indicated that, for all cells prepared at different firing temperatures, the SEM and XRD did not indicate any differences between them. By using EIS, however, two impedance arcs were obviously observed. This first arc was found at high frequency region ( 10 Hz). The high frequency arc corresponded to the impedance of electron-transfer and ion-transfer processes occurring at the current collector/electrode and electrode/electrolyte interfaces. The low frequency arc was the convoluted contribution of the diffusion processes (non-charge transfer processes). Changing firing temperature, measuring temperature and oxygen pressure leads to changing of symmetrical cell performances. The activation energy of these symmetrical cells was around 1.5–2.0 eV depending on the firing temperature and oxygen pressure.

Due to low water absorption, high bending strength and abrasion resistance, and excellent chemical and frost resistance, porcelain building ceramic tiles are the highest increase in production and sales over all other kind of building ceramic tiles materials. In this paper, porcelain building ceramic tiles was prepared by a fast firing process of rare earth tailings as the main raw material, low fused sand and Zhuji porcelain sand et al mixture. Effects of firing temperature and forming pressure on the sintering behavior and mechanical property of porcelain building ceramic tiles were studied. The sintering behavior of the fired samples was evaluated by linear shrinkage and water absorption. The fired samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and bending strength measurements. The sample is pressured at 15 MPa and sintered at 1180 °C and endowed with 0.04% of the water absorption and 51 MPa of the bending strength, due to denser microstructure. The obtained results would contribute to save natural resources and protect environment.

Manufacturing of ceramic products using calamine hydrometallurgical processing wastes

Utilization of marble waste as a sustainable replacement for calcareous in the manufacture of red-firing wall tiles

Effects of firing temperature and Al additive on the microstructures and properties of SiC-CA6 composite refractories

The rising demand for environmentally sustainable construction materials has encouraged research into alternative materials for lightweight brick production. In this context, this study investigates the potential of incorporating natural Moroccan pozzolan into clay bricks formulations to enhance their physical, mechanical and structural properties. It also seeks to optimize brick performance by exploring the combined effects of pozzolan content, firing temperature and firing duration using a statistical approach. Initial characterization of raw materials was performed using XRD, DTA-TGA, XRF and SEM-EDX analyses. Three initial mixtures were prepared: a control sample and two formulations containing 5 and 10% of weight pozzolan, respectively, all fired at 900°C. Results showed that bricks with 5% pozzolan exhibited the highest density (1.63 g/cm3) and flexural strength (7.07 MPa), outperforming both the control and 10 wt.% samples. To further understand and optimize the combined effects of firing temperature, duration and pozzolan content, response surface methodology (RSM) was employed. Seventeen formulations were tested, and statistical analysis identified the optimal conditions as 7.8wt.% pozzolan, a firing temperature of 901°C and a firing duration of 2.8 h. Under these conditions, the resulting lightweight-bricks showed improved properties that meet standard building requirements, confirming their potential for practical application in sustainable construction.