Slip Casting Method Research Articles

The Effect of Calcium Carbonate Added into Mambong Clay

Mambong clay is a traditional pottery that originally from Kampong Mambong, Kuala Krai, Kelantan, Malaysia. The new fabrication technique of this pottery is the slip casting technique. However, the innovation of Mambong pottery does not only limited to the fabrication technique, but also the materials used in the fabrication in order to improve its physical properties. Calcium carbonate (CaCO3) is one of the materials that can be used in this fabrication as an additive due to the ability to stabilize the clay soil and improves the clay physical properties. In this study, the various CaCO3 contents (0, 5, 10, and 15%) were investigated to get the optimum amount of CaCO3 to improve the physical properties of Mambong clay by using slip casting method. Mambong clay with different amount of CaCO3 addition was compared in term of microstructure, density, porosity, shrinkage, and flexural strength.

Slip-casting process of MgO–Y2O3 nanocomposite: Investigation of powder synthesis method

In this paper, yttria-magnesia composite nano-powders with a chloride and nitrate-acetate precursors were synthesized using the sol-gel method. The green body of MgO–Y2O3 nanocomposite was fabricated by the slip-casting method and the rheological properties were improved by adding Dolapix CE64 to the slurries as a dispersant agent. The Y2O3–MgO nanocomposite slurry with a solid loading of 60 wt% and the pH of 12 was obtained using 1 wt% Dolapix CE64.The X-ray diffraction (XRD), Field Emission Scanning Microscope (FESEM) and Brunaure-Emmett-Teller (BET) tests were used.Various slip/slurry characterization techniques such as sedimentation, viscosity measurements and porosimetry were used to optimize the slip casting parameters. The relative densities of the green and sintered body (1400 °C/2 h) were 50% and 86%, respectively. The FESEM results of the sintered yttria-magnesia composite with the chloride precursors showed the more uniform distribution of MgO and Y2O3 phases than the nitrate precursors.

Preparation of a Zirconia-Based Ceramic Membrane and Its Application for Drinking Water Treatment

This work concerns the preparation of a mineral membrane by the slip casting method based on zirconium oxide (ZrO2) and kaolin. The membrane support is produced from a mixture of clay (kaolin) and calcium carbonate (calcite) powders using heat treatment (sintering). Membrane and support characterization were performed by Scanning Electron Microscopy (SEM), X-ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Raman Spectroscopy. The prepared mineral membrane was tested to treat drinking water obtained from different zones of the El Athmania (Algeria) water station (raw, coagulated, decanted, and bio filtered water). Experimental parameters such as permeate flux, turbidity, and total coliforms were monitored. The results showed that the mineral membrane was mainly composed of SiO2 and Al2O3 and the outer surface, which represented the membrane support, was much more porous than the inner surface where the membrane was deposited. The permeate flux of the raw water decreased with filtration time, due to a rejection of the organic matters contained in the raw water. Moreover, the absence of total coliforms in the filtrate and the increase in concentration in the concentrate indicate that the prepared mineral membrane can be used for drinking water treatment.

Thermoanalytical and dilatometric studies of the Al2O3\u2013Cu\u2013Mo hybrid composite

The present research is focused on the characterization of the composites from Al2O3–Cu–Mo system. The composites were prepared by slip casting method and subsequent sintering of green bodies in a reduced atmosphere. Two series of samples with different volume content of metallic powders were produced in the work: 10 vol% and 15 vol% of metal content with respect to the total solid-phase content. The sintering process of the composites was analyzed in detail. The linear shrinkage of the composites was measured. The shrinkage curves were obtained by dilatometry test in a heating mode. The composites were characterized by DTA/TG analyses and thermal conductivity. The composites were characterized by XRD, SEM, and EDX. The hardness was measured by Vickers hardness tester. Moreover, the Brazilian test was performed to determine the tensile mechanical properties of the composites. Fractography investigation was carried out as well. Dilatometric tests showed that the increase of the metallic phase volume in the ceramic matrix causes a decrease in the starting temperature of densification. Simultaneously, dilatometric experiments indicated that an increasing amount of metallic particles into the ceramic matrix increases the temperature of maximum densification and decreases the total shrinkage of the composites during sintering. The DTA/TG showed the characteristics of the dispersant decomposition to the atmosphere during thermal treatment and increase of mass connected with the oxidation of metals. Fractography results revealed good adhesion between Al2O3 matrix and the metallic phase. The observation allowed to conclude that the Al2O3 matrix surface is characterized by the brittle fracture mechanism.

Synthesis of in-situ mullite foam using waste rice husk ash derived sol by slip-casting route

In this study, mullite foam ceramic is synthesized via a simple slip-casting method without using any pore producing additive or agent, in order to avoid the emission of greenhouse gases (mainly CO2) from the matrix. Waste rice husk ash (RHA) extracted sol (solid contain ~7.5 wt%) as an alternative of conventional silica sources along with active alumina is used for the preparation of slip-casting slurry. About 22 wt% solid containing slurry is casted in the plaster of paris (POP) mold. The casting mass is dried at 110 °C and fired at 1100 °C, 1200 °C, 1250 °C, 1300 °C, 1350 °C, and 1400 °C. Several properties like phases, microstructure, porosity, density, mechanical strength, and thermal conductivity are comprehensively investigated with the foam samples. At 1250 °C fired sample is retained mullite dominating phase in the matrix. The single-phase mullite is formed at 1300 °C fired sample with 75.99% total porosity, 11.07 MPa compressive strength, and thermal conductivity of 0.153 W/m·k. Furthermore, the strength value and thermal conductivity are increased and porosity is reduced with the increasing firing temperature. The obtained results exhibit that the waste RHA derived sol is capable to produce low-temperature in-situ mullite foam through slip-casting route without generating the pollutants (mainly CO2↑).

The influence of metal phase composition on microstructure and mechanical properties of Al2O3-Cu-Cr ceramic metal composites

Ceramic metal composites from the ternary Al2O3-Cu-Cr system were fabricated with the use of the slip casting method. Densities of the obtained composites with 15 vol.% of metal content and different percentage composition of Cu and Cr were examined by the Archimedes method. The samples’ microstructures, observed by scanning electron microscope, were analysed with image analysis program in order to determine size distribution of the metallic areas in the structure. Phase composition of the sintered samples was examined by X-ray diffraction analysis. Vickers hardness of the samples was tested along with their fracture toughness with the use of the Vickers indentation technique. The conducted research revealed the correlation between the microstructure and mechanical properties of the obtained specimens. It has demonstrated the possibility of manufacturing composites from ternary system with the use of the slip casting method. It was revealed that the addition of the chromium particles to the metallic phase enhances hardness of the composites. Also, the metallic phase composition of the samples affects mechanism of the crack propagation in the material. Although the mechanical properties have been improved, it was found that the density of the samples was not satisfying and the need for further analysis has been identified.

Microstructure and mechanical properties of Al2O3-Cu-Ni hybrid composites fabricated by slip casting

This work focuses on developing the fabrication method of hybrid composites based on Al2O3-Cu system with the addition of nickel phase. The composites were prepared by slip casting and the slurries with a high concentration of solid content were used. The sintered composites were characterized by XRD, SEM and EDX. Selected physical proprieties, namely hardness, fracture toughness and bending strength were also determined. The microstructure and its influence on the mechanical properties were investigated. XRD analyses revealed that the obtained composites contained Al2O3, Ni, Cu and solid solution CuNi phases. The use of slip casting method allowed the production of the composites characterized by relative density of _96%. An increase in metallic phase concentration caused a decrease in Vickers hardness and increased the fracture toughness of the Al2O3-Cu-Ni materials compared to the Al2O3 samples. The results with high cognitive value and application potential were obtained. This research enabled the foundations of an innovative method of forming hybrid composite structures, which combined the best features of ceramics (hardness, resistance to high temperature) with metal properties (crack resistance, good electrical conductivity). This type of composite can be used for temperature, conductivity and flow sensors.

The effect of kaolin and silica variation on the properties of porcelain insulators

Clay, Al2O3, feldspar and silica have been used to produce shackle-type porcelain insulators using slip casting method. The amounts of silica and kaolin were varied from 10 to 30 wt. % while keeping the amounts of other constituents constant. The samples were bisque fired at 900 °C, sintered at 1200 °C for 1 hour glazed using borax fritz. The results showed that as the amount of kaolin decreased, apparent porosity and water absorption increased from 9-19 % and 7-12 % respectively. The bulk density and linear shrinkage decreased from 1.94-1.12 g/cm3 and from 12.5 % - 7 % respectively. Breakdown voltages ranging from 23 kV to 35 kV were obtained while the highest insulation resistance value of 50GΩ was for the sample with 55 % clay, 15 % silica and 25 % feldspar and 5 % Al2O3. The results indicate that moderate variations in kaolin and silica content can be used to produce porcelain insulators for commercial applications. Keywords: Electrical porcelain, Shackle insulator, Kaolin, Feldspar, Processing.

Effect of additives on slip casting rheology, microstructure and mechanical properties of Si3N4/SiC composites

The SiC/Si3N4 composites were fabricated with sintering process. To produce SiC/Si3N4 composite components, slurry mixtures containing Si/SiC powders were used by the slip casting method. In order to investigate the effect of dispersants and additives on the rheological properties and the body casted, slurries with concentration of 70% solid weight were prepared. It included a mixture of silicon and silicon carbide with weight ratios of 30 wt% and 70 wt%, respectively, and various weight percentages of Ball clay as lubricant and Tiron (sodium salt of benzene disulfonic acid) as dispersant at pH value of 7. After preparing the green bodies by slip casting method by using plaster mold, the samples were sintered at 1450 °C inside an atmospheric-controlled furnace under a pressure of 0.12 MPa of nitrogen gas for 2 h. By examining the rheological properties of the slurry and the sintering properties, it was concluded that the best slurry was obtained in terms of viscosity, density, porosity and strength using 5 wt% Ball clay and 0.5 wt% Tiron. Phase transformations, microstructure and morphology of the sintered specimens were accomplished by Field Emission Scanning Electron Microscopy (FESEM) examination and X-ray diffraction experimental analysis. XRD and FESEM results demonstrated that the composite fabricated by slurry containing 5 wt% Ball clay and 0.5 wt% Tiron had the least porosity without SiO2 phase.

Segmented Phase of Ultraviolet (UV) Curable Thermoset Polyurethanes-Graphite (TPU-G) Composites

Segmented thermoset polymeric materials properties mainly classified through its carbonyl hydrogen bonding. The addition of graphite particle loading in polymeric materials tailored the functional characteristic of the composites. Therefore, the carbonyl hydrogen bonding in the hard segments of the synthesized segmented ultraviolet (UV) curable thermoset polyurethanes-graphite (TPU-G) composites was identified. This composites based green polymer incorporated with varying graphite particles loading were prepared through slip casting method which cure upon UV light. These result in an enhancement of the carbonyl hydrogen bonding which tribute to degree of phase separation (DPS %) in the TPU-G composites ranged from 10-20%, as compared to that in the pure TPU. In addition, the spectroscopy detects the formation of carbonyl hydrogen groups within the TPU-G composites although they are prone to chain scission and undergo photo oxidation subjected to ultraviolet (UV) curing. Upon UV curing, higher graphite weight loading (TPU-G20, TPU-G25 and TPU-G30 composites), shows higher and stable DPS% value, attribute to soft segment- soft segment and hard segment- hard segment establishment. Therefore, the graphite particles dominantly absorb the incident radiation instead of thermoset polyurethane without changing its based.

Characterization of alumina crucible made from aluminum industrial waste

The use of aluminum waste sludge as a raw material in the ceramic industry was studied due to its economical, energy, and environmental advantages. This study focused on preparation and characterization of alumina crucibles made from aluminum industrial waste for the purpose of glass melting. The main objective of this project was to reduce or replace both alumina powder and alumina crucibles imported from abroad. The trial formulas were composed mainly of calcined aluminum waste (CAW) from aluminum factory. Additionally, sodium silicate and sodium salts of polycarboxylic acid were used as deflocculants while polysaccharide was used as a binder. The crucibles were shaped by the slip casting method and then sintered at 1600 and 1700 °C. The water absorption, bulk density, apparent porosity, and 3-point bending strength were investigated. After sintering at 1600 and 1700 °C, the crucible with 75 wt% of aluminum waste (75AC formula) showed 0.18 and 0.06% water absorption, 3.41 and 3.36 g/cm3 bulk density, 0.61 and 0.20% apparent porosity, and 139.11 and 159.84 MPa bending strength, respectively. The coefficient of thermal expansion between 25 and 1000 °C of 75AC composition was 6.9807 × 10−6/°C and the crucibles passed three cycles of 20–200 °C thermal shock resistance testing. The resulting crucibles were successful in the trial for glass melting between 1450 and 1500 °C without either breaking or affecting the glass component. Calculation of the production costs for these lab-scale trials revealed that the crucible made from aluminum waste was about 70% cheaper than that made from commercial alumina. As a result, this study indicated that the alumina crucible made from aluminum industrial waste performed comparably with the commercial crucible being used for glass melting purposes.

Microstructure, physical and mechanical properties of kaolin–diatomite composite reinforced with CaCO3•

The present work reports the microstructure, physical and mechanical properties of a material composed of kaolin, diatomite and calcium carbonate reinforcement (CaCO3). The ceramic prototypes were shaped by the slip casting method and sintered at temperatures between 800 °C and 1100 °C. The morphology and average pore size was analyzed by Scanning Electron Microscopy (SEM) and the mineralogical phases were determined by X-Ray Diffraction (XRD). The apparent density was established by the mercury immersion method according to the E – 8B Standard of the Institute of Ceramic Technology (ITC); the percentage of absorption was determined by the boiling method according to ISO 10545-3 standard; linear contraction was studied in three directions: long, wide and high. The study of the mechanical resistance to compression followed the procedure established at ASTM C773–88 standard and the breaking modulus was calculated by the three-point bending test, according to ISO 10545–4. Results show that the material structure is affected with increasing temperature reporting a decrease in quartz phase from 51.16 % to 33.81 %. Percentage of absorption revealed its most significant variation between 950 °C and 1100 °C with a decrease of 21 % approximately. Mechanical resistance values showed wide dispersion which was attributed to the different orientations in which the material failed during each test. According to the pore diameters found, the compound is characterized by being macro and mesoporous facilitating its application in catalysis, photochemistry, microelectronics and other microfiltration media

Electrochemical synthesis of In2O3 nanoparticles for fabricating ITO ceramics

In2O3 nanoparticles approximately 50–100 nm in size were successfully synthesised using an electrochemical method utilising aqueous NH4Cl solution as electrolyte followed by calcination at 400 °C for 3 h. Scanning and transmission electron microscopy analyses revealed that the obtained In2O3 nanoparticles were uniform, monodisperse, and near-spherical. The optical performance of the In2O3 nanoparticles was investigated using UV–Vis and photoluminescence spectra. The In2O3 nanoparticles were used to fabricate tin-doped indium oxide (ITO) ceramics using the slip casting method, and the sintering behaviours and microstructures of the ITO ceramics were studied in detail. The results demonstrated that ITO ceramics sintered at 1600 °C for 8 h exhibited high density (7.135 g/cm3) and low resistivity (0.137 mΩ⋅cm), which indicated their great potential for fabricating ITO films featuring excellent properties.

Studying the influence of properties of initial ZrO2-(7 %)Y2O3 powders on properties of ceramic products

The paper focuses on the possibility of forming ceramic products by the method of slip casting without the stage of mechanical grinding of powders. We studied the influence of pH value of hydroxides precipitation and hydrothermal treatment on the properties of ZrO2-(7 %)Y2O3 powders, and on the mechanical properties of ceramic products made from synthesized ZrO2-(7 %)Y2O3 powders without a grinding stage. Findings of research show that the quality of ceramic products based on zirconium oxide is more influenced by the specific surface area, rather than the particle size of the initial powders

In-situ carbon coated manganese oxide nanorods (ISCC-MnO2NRs) as an electrode material for supercapacitors

The fabrication of energy storage devices with lowering the cost and improving the performance has always been the need for society. Therefore, supercapacitors with special features such as light-weight, easy portability and remarkable charging/discharging rate capability have widely been studied in the literature. In the present work, In-situ carbon coated manganese oxide nanorods (ISCC-MnO2NRs) have been studied for the supercapacitor application. ISCC-MnO2NRs were prepared by slip casting method followed by annealing at 1200 °C. During heat treatment, sucrose has transformed into conducting carbon and coated on the surface of MnO2. ISCC-MnO2NRs were examined by FEG-SEM, FEG-TEM, XRD, FT-IR, BET and Raman spectroscopy. The measurement of the electrochemical properties of the material was carried out in the two-electrode configuration using 1 M Na2SO4 aqueous solution as an electrolyte. The specific capacitance of ISCC-MnO2NRs was found to be 28.24 F/g at the current density of 1 A g−1 with energy density of 0.98 Wh/kg. This work suggests ISCC-MnO2NRs may be a promising electrode material for the supercapacitor.

DEVELOPMENT OF CERAMIC MICROFILTRATION SUPPORT FROM MOROCCAN SAHARA CLAY

<p>The new ceramic microfiltration support prepared from Moroccan clay (Laayoune region, South of Morocco) is reported in this paper. To optimize the support elaboration conditions, the powder clay is mixed with organic additives and water. The formed paste is shaped by using an extrusion processing and then sintered at 950 °C. The ceramic supports present a porosity and mechanical strength of 44 % and 12MPa respectively. The layer filtration deposition has been carried out by the slip casting method, in order to test its operation in textile effluents treatment.<strong></strong></p>

Production and Thermophysical Properties of BeO Ceramics with the Addition of Nanocrystalline Titanium Dioxide

A slip casting method was used to produce samples of BeO-based composite ceramics with additions of 5 – 30 wt.% of nanocrystalline TiO2 powder. It was established that slip casting does not provide the maximum density of ceramic samples. This may cause some effect on its thermophysical properties. A microstructure of (BeO + TiO2)-ceramics was studied, as well as variations in its specific heat capacity at constant pressure, thermal diffusivity and thermal conductivity depending on the amount of additive at room temperature and in the range of 300 – 800 K. The established patterns will help designing more powerful absorbers of scattered microwave radiation based on (BeO + TiO2 )-ceramics.

Production and thermophysical properties of BeO ceramics with the addition of nanocrystalline titanium dioxide

Samples of composite ceramics based on BeO with additions of 5‒30 wt. % of nanocrystalline powder TiO2were produced by slip casting method. It is established that slip casting does not provide the maximum density of ceramic samples. It can have some effect on its thermophysical properties. The microstructure of (BeO + TiO2)-ceramics, as well as the change of heat capacity at constant pressure, thermal diffusivity and thermal conductivity depending on the amount of additive at room temperature and in the range of 300‒800 K are investigated. The established patterns will help to design more powerful absorbers scattered microwave radiation based on (BeO + TiO2)-ceramics.Ill. 6. Ref. 17. Tab. 3.

DEVELOPMENT OF CERAMIC MICROFILTRATION SUPPORT FROM MOROCCAN SAHARA CLAY

The new ceramic microfiltration support prepared from Moroccan clay (Laayoune region, South of Morocco) is reported in this paper. To optimize the support elaboration conditions, the powder clay is mixed with organic additives and water. The formed paste is shaped by using an extrusion processing and then sintered at 950 °C. The ceramic supports present a porosity and mechanical strength of 44 % and 12MPa respectively. The layer filtration deposition has been carried out by the slip casting method, in order to test its operation in textile effluents treatment.

Characterization and production of slip casts mullite–zirconia composites

In this study, mullite–zirconia composites were prepared by reaction sintering of alumina, kaolinite zircon and colemanite powder. Slip casting method was also employed for production of these composites. Two different compositions were prepared with and without colemanite additive. The main purpose of this work was to determine the optimum conditions for mullite–zirconia synthesis in addition to the effects of starting composition, solid concentration of aqueous suspensions and sintering temperature. The resulting sintered materials were characterized in terms of bulk and relative density, firing shrinkage, XRD and SEM. XRD peaks suggested fully developed mullite and zirconia phases by reaction sintering of zircon, kaolinite, alumina and colemanite phases. Zircon usually dissociates at a temperature higher than 1650 °C. However, it has been shown in this study that zircon dissociates at about 1450 °C due to the presence of colemanite. The results of the study indicate that 90% of relative density was achieved as the solid concentration is increased up to 55% in case for slip-casted specimens with colemanite additive (MZC55 with 55% solid concentration). The microstructure of all composites is composed of irregularly shaped mullite grains and round-shaped zirconia grains which are distributed intragranularly and intergranularly.