Sintering, physicomechanical, thermal expansion and microstructure properties of cordierite ceramics based on utilizing silica fume waste

Mullite-cordierite ceramics was prepared by the three composition of talc, kaolin (kaolin from Naratiwas in Thailand) (NT) and alumina. The different amounts of alumina (5, 10, 15 and 20 wt%) were added to produce various mullite-cordierite alumina mixtures which are denoted as NA, NB, NC and ND, respectively. The mixtures were pressed into rectangular shapes by hydraulic press with the pressure of 150 kg/cm2 then sintered at temperature of 1300 °C and 1350 °C for 2 hours. The morphology of the synthesized mullite-cordierite samples were characterized by x-ray diffraction spectroscopy (XRD), and physical-mechanical properties were investigated. Mullite-cordierite was successfully synthesized. The XRD result was represented phases of mullite and cordierite. The NA samples sintered at temperature of 1300 °C indicated the best physical-mechanical properties including bulk density (2.23 g/cm3), flexural strength (44.4 MPa) and thermal expansion coefficients (5.00x10-6). The other NA samples sintered at temperature of 1350 °C exhibited the bulk density, flexural strength and thermal expansion coefficients are 2.21 g/cm3, 47.8 MPa and 4.99 x10-6, respectively. The thermal expansion coefficient of the NT sintered samples have been plotted the length change relative to measuring temperature ranging of 30-1200 °C. The suitable condition of the synthesized mullite-cordierite ceramics is finally obtained the NA samples with 5 percent weight of alumina composition sintered at the temperature of 1350 °C.

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Effect of WO3 on the Performances of Cordierite Ceramics Synthesized by Using Kyanite as Raw Materials

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.281.99 ◽

2018 ◽

Vol 281 ◽

pp. 99-104

Author(s):

Meng Li Qin ◽

Xi Tang Wang ◽

Zhou Fu Wang ◽

Yan Ma ◽

Hao Liu

Keyword(s):

Thermal Expansion ◽

Phase Composition ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Intermediate Phase ◽

Raw Materials ◽

Low Thermal Expansion ◽

Cordierite Ceramics ◽

The Right

In order to synthesize cordierite ceramics with low thermal expansion coefficient and good properties, in our work, the cordierite ceramics were prepared by using talc, natural containing zirconium kyanite, common kyanite and industrial Al2O3 as raw materials, introducing the right amount of WO3 (introducing tungsten acid) as catalyst. The effects of the introduced WO3 on the phase composition, sintering characters, microstructure and thermal expansion coefficient of the cordierite ceramics were investigated. The results show that the introduction of WO3 can eliminate the intermediate phase magnesia-alumina spinel and promote the formation of cordierite; the as-prepared cordierite ceramics synthesized by using natural containing zirconium kyanite as raw materials have high densification degree and low thermal expansion coefficient (1.53×10-6/°C, Rt~1000 °C).

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Microstructures of La-Doped Low Thermal Expansion Cordierite Ceramics

Mechanical Properties and Performance of Engineering Ceramics and Composites VII - Ceramic Engineering and Science Proceedings ◽

10.1002/9781118217467.ch15 ◽

2012 ◽

pp. 153-162 ◽

Cited By ~ 1

Author(s):

Hiroto Unno ◽

Shoichi Toh ◽

Jun Sugawara ◽

Kensaku Hattori ◽

Seiichiro Uehara ◽

...

Keyword(s):

Thermal Expansion ◽

Low Thermal Expansion ◽

Cordierite Ceramics ◽

La Doped

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Influence of Additives on Performance of Silicon Carbide Refractory

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.2277 ◽

2012 ◽

Vol 538-541 ◽

pp. 2277-2280

Author(s):

You Fu Guo ◽

Ming Yue Zheng ◽

Jing Long Bu ◽

Yue Jun Chen ◽

Li Xue Yu ◽

...

Keyword(s):

Silicon Carbide ◽

Thermal Expansion ◽

Bulk Density ◽

Thermal Shock ◽

Silica Fume ◽

Thermal Shock Resistance ◽

Bending Strength ◽

Carbide Refractory ◽

Shock Resistance ◽

Silicon Carbide Refractory

Silicon carbide with diffierent granularity was used as raw material, quartz, silica fume, aluminum powder or alumina was used as additive with dosages of 1% (in mass, similarly hereinafter), 3% and 5%. Silicon carbide refractory material was prepared in oxidizing atmosphere at 1400 °C for 3 h. Performence of samples were researched by measurements of apparent porosity, bulk density, bending strength at room temperature, thermal shock resistance and thermal expansion rate, and analyzed by SEM. The results showed that samples added silica fume have low thermal expansion rate and apparent porosity, high bending strength and bulk density, good thermal shock resistance, compact texture as well. It can be deduced that 5% silica fume plays the excellent role to improve integrated performance of silicon carbide refractory material.

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