Preparation of Sialon from Solid Wastes by Colloidal Process

Based on the slip casting and the preparation of sialon synthesized from clay, fly ash and gangue by the carbothermal reduction nitridation, the influences of compositions, dispersant additive and sintering process on the properties of materials have been investigated in present work. The experimental results indicate that disposal of fly ash via a pickling process can greatly reduce the content of iron, and the effect is obvious with increasing the concentrations of hydrochloric acid and pickling temperature. Therefore the component of the final product can be purified. It is also noted that the final density of the sintered body using colloidal process is superior to that of using conventional dry pressing, although the slightly higher green density is observed in dry pressing body because of high compaction pressure.

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Colloidal Process of Magnesia-Carbon Refractory and Its Sintering Characteristic

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.280-283.1675 ◽

2007 ◽

Vol 280-283 ◽

pp. 1675-1678 ◽

Cited By ~ 2

Author(s):

Li Hua Xu ◽

Zhi Fei Cheng ◽

Fang Lian ◽

Ti Zhuang Wang ◽

Yun Yao

Keyword(s):

High Performance ◽

Ph Value ◽

Compaction Pressure ◽

Slip Casting ◽

Metallurgical Industry ◽

Green Density ◽

Structural Ceramics ◽

Dry Pressing ◽

Excellent Thermal Property ◽

Selection Of

Carbon-containing refractories are widely used in metallurgical industry due to their excellent thermal property and resistance to corrosion by molten iron. In the present work, slip casting colloidal process, which is used to fabricate high performance structural ceramics, has been introduced into the preparation for magnesia-carbon refractory with selection of suitable dispersant. The results indicated that the curve of zeta-potential of magnesia was similar with that of carbon just containing dispersant and the homogenized mixtures were attained under a controlling of low pH value. Three kinds of preparing routes for green bodies were designed, and all of the final densities and the resultant hardness of sintered bodies using colloidal process were superior to these of the specimen using conventional dry pressing, whereas its high green density can be plausibly observed in dry pressing body because of high compaction pressure used.

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Study on Preparation and Property of Carbon Fiber/HA Composites by Centrifugal Slip Casting Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1058.180 ◽

2014 ◽

Vol 1058 ◽

pp. 180-184

Author(s):

Qiang Li ◽

Jing Yuan Yu ◽

Xiu Juan Meng

Keyword(s):

Fracture Toughness ◽

Carbon Fiber ◽

Carbon Fibers ◽

Bending Strength ◽

Slip Casting ◽

Rheological Characteristic ◽

Green Density ◽

Aminobenzoic Acid ◽

Casting Method ◽

Dry Pressing

In this paper, centrifugal slip casting method was use to prepare carbon fiber/HA composites using the nanoHA particles and carbon fibers as initial materials. The morphology of the carbon fiber after modification of p-aminobenzoic acid was observed. The rheological characteristic of the carbon fibers/HA slurries was studied. The effects of the centrifugal acceleration on green density uniformity of carbon fiber/HA composites were analyzed. The bending strength and fracture toughness of carbon fiber/HA composites were measured. The results show the roughness of carbon fibers treated by p-aminobenzoic acid increases. At the pH of 10 and 5 wt% dispersant, the HA slurries with 3 vol% carbon fibers have good fluidity. After centrifuged at 2860 G for 30 min, the green compacts of HA composites have high and uniform the green density. After sintered at 1100°C for 1h, compared with carbon fiber/HA composites prepared by dry pressing, the modified carbon fiber/HA composites prepared by centrifugal slip casting have higher bending strength and fracture toughness of 89.4 MPa and 1.92MPa1/2, respectively.

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The Preparation of Red Mud Foam Lightweight Thermal Insulation Material

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.541-542.104 ◽

2014 ◽

Vol 541-542 ◽

pp. 104-107

Author(s):

Long Ma ◽

Guo Zhong Li

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Thermal Insulation ◽

Red Mud ◽

Raw Materials ◽

Insulation Material ◽

Test Results ◽

Sintering Process ◽

Thermal Insulation Material ◽

Properties Of Materials

Red mud foam lightweight thermal insulation material was prepared by red mud, fly ash, cement as main raw materials, adding a certain amount of adhesive, through ingredients, mixing, molding, foam, sintering process. The influence of the ratio of red mud and fly ash on the properties of materials was studied and the mechanism of influence was analyzed. The test results show that performances of the samples were best when the ratio of red mud and fly ash is 5:4 and its flexural strength is 0.44MPa, compressive strength is 1.23MPa, density is 481kg/m3.

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Sintering Process and Characteristics of Glass-Ceramics from Coal Fly Ash

Advances in Powder and Ceramic Materials Science - The Minerals, Metals & Materials Series ◽

10.1007/978-3-030-36552-3_1 ◽

2020 ◽

pp. 3-13

Author(s):

Li Zeng ◽

Hongjuan Sun ◽

Tongjiang Peng ◽

Wenmiao Zheng

Keyword(s):

Fly Ash ◽

Coal Fly Ash ◽

Glass Ceramics ◽

Sintering Process

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Influence of prolonged sintering time on density and electrical properties of isothermally sintered cordierite-based ceramics

Science of Sintering ◽

10.2298/sos1302157p ◽

2013 ◽

Vol 45 (2) ◽

pp. 157-164 ◽

Cited By ~ 4

Author(s):

A. Peles ◽

N. Djordjevic ◽

N. Obradovic ◽

N. Tadic ◽

V.B. Pavlovic

Keyword(s):

Electrical Properties ◽

Mechanical Activation ◽

Compaction Pressure ◽

High Energy ◽

Sintering Process ◽

X Ray Diffraction ◽

Air Atmosphere ◽

Atomic Force ◽

Sintering Time ◽

High Energy Ball Mill

Mechanical activation is a commonly used and relatively fast and inexpensive procedure for sample preparation before the sintering process. Cordierite, a stoichiometric mixture of three different oxides (2MgO?2Al2O3?5SiO2) is a very attractive, widely used high-temperature ceramic material. The mechanical activation of the starting mixtures with 5.00 mass% TiO2 was performed in a high energy ball mill during 10-80 min. The applied compaction pressure before the sintering process was 2t/cm2, based on our recent investigation. The sintering process was performed at 1350oC for 2h and 4h in air atmosphere. X-ray diffraction was used to analyze the phase composition of non-activated and 80 min activated samples, sintered for 2 and 4h, respectively. Scanning electron microscopy was performed to analyze the microstructure of both compacted and sintered samples. Atomic force microscope was used to investigate the surface of the sintered samples. This paper investigates the influence of prolonged sintering time on the densities of the sintered samples, along with electrical properties.

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Effect of Sintering Temperature on the Mechanical Properties of Nanostructured Ceria-Zirconia Prepared by Colloidal Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1125.401 ◽

2015 ◽

Vol 1125 ◽

pp. 401-405

Author(s):

Mohamed M. Aboras ◽

Andanastuti Muchtar ◽

Noor Faeizah Amat ◽

Che Husna Azhari ◽

Norziha Yahaya

Keyword(s):

Mechanical Properties ◽

Sintering Temperature ◽

Slip Casting ◽

Tetragonal Zirconia ◽

Cold Isostatic Pressing ◽

Sintering Process ◽

Colloidal Processing ◽

Tooth Color ◽

Biological Compatibility ◽

Nanostructured Ceria

The demand for tetragonal zirconia as a dental restorative material has been increasing because of its excellent mechanical properties and resemblance to natural tooth color, as well as its excellent biological compatibility. Cerium oxide (CeO2) has been added to yttria-stabilized zirconia (Y-TZP), and studies have demonstrated that the stability of the tetragonal phase can be significantly improved. Y-TZP with 5wt% CeO2 as a second stabilizer was developed via colloidal process, followed by a suitable sintering process. According to the literature, the sintering process is the most crucial stage in ceramic processing to obtain the most homogeneous structure with high density and hardness. This study aims to investigate the effect of sintering temperature on the mechanical properties of nanostructured ceria–zirconia fabricated via colloidal processing and slip casting process with cold isostatic pressing (CIP). Twenty-five pellet specimens were prepared from ceria–zirconia with 20 nm particle size. CeO2 nanopowder was mixed with Y-TZP nanopowder via colloidal processing. The consolidation of the powder was done via slip casting followed by CIP. The samples were divided into five different sintering temperatures with. Results from FESEM, density and hardness analyses demonstrated statistically significant increase in density and hardness as the sintering temperature increased. The hardness increased from 4.65 GPa to 14.14 GPa, and the density increased from 4.70 to 5.97 (g/cm3) as the sintering temperature increased without changing the holding time. Sintering Ce-Y-TZP at 1600 °C produced samples with homogenous structures, high hardness (14.14 GPa), and full densification with 98% of the theoretical density.

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Dense, bubble-free ceramic deposits from aqueous suspensions by electrophoretic deposition

Journal of Materials Research ◽

10.1557/jmr.2001.0048 ◽

2001 ◽

Vol 16 (2) ◽

pp. 321-324 ◽

Cited By ~ 75

Author(s):

Tetsuo Uchikoshi ◽

Kiyoshi Ozawa ◽

Benjamin D. Hatton ◽

Yoshio Sakka

Keyword(s):

Electrophoretic Deposition ◽

Current Density ◽

Bubble Formation ◽

Slip Casting ◽

Green Density ◽

Laminate Composites ◽

Aqueous Suspensions ◽

Sintering Properties ◽

Current Densities ◽

Positively Charged

The characteristics of electrophoretic deposition (EPD) of positively charged particles onto a cathode were investigated using aqueous alumina and zirconia suspensions. The deposition was performed using several kinds of metal substrates at different current densities. For most substrate materials, a large number of macropores appeared in the deposit, and their size increased with the current density due to gas bubble formation. However, no macropores were formed in the deposit on a palladium substrate, regardless of the current density. The green density and sintering properties of the EPD deposits on a palladium substrate from aqueous suspensions were the same as from slip casting. Bubble-free zirconia/alumina laminate composites were also fabricated by EPD from aqueous suspensions.

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Comparison of Different Alumina Powders for Aqueous Tape Casting Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.820.172 ◽

2015 ◽

Vol 820 ◽

pp. 172-177

Author(s):

Fernanda P. Santos ◽

Ediana Gambin ◽

Cristina Moniz A. Lopes ◽

Rosa Maria Rocha

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Tape Casting ◽

Casting Process ◽

Aqueous System ◽

Solid Concentration ◽

Green Density ◽

Commercial Alumina ◽

Acrylic Latex ◽

Final Density

Tape casting process was used to produce Al2O3 substrates in an aqueous system with acrylic latex emulsion as binder. The present work studied the slurry formulations in aqueous medium of Al2O3 powders with different particle size distribution and made correlation to the green and sintered tapes. Two commercial alumina powders, one sub-micrometric and other micrometric were used. Compositions of Al2O3 slurries with 80 and 83 wt% of solids were prepared by dispersing the powders in water with a dispersant with subsequently additions of 7 and 10 wt% of binder. Sub-micrometric Al2O3 resulted in a high densification tapes regardless solid concentration and binder amount in the slurry, though green density was affected. For micrometric alumina, increasing the solid concentration resulted in a little higher final density.

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