Sealing Glass‐Ceramics with Near Linear Thermal Strain, Part I: Process Development and Phase Identification

Dielectric glass and glass-ceramics were derived from Na2O-Nb2O5-Al2O3-SiO2 system. Small amount of TiO2 were also introduced into glass compositions to study crystallization behavior of the glass with present of this nucleating agent. Conventional melt-quenching technique was employed for a glass production and the selected bulk glass samples were subjected to the heat-treatment process at appropriate temperature. After six different glass compositions were produced, and by observation with necked eyes, all obtained glass samples are in light brown color and some samples were opaque due to crystallization took place during quenching. Phase identification through XRD patterns show that there were 3 phases, NaNbO3, NaNbO8 and a sodium aluminum silicate compound, found in those opaque glass samples. NaNbO3 is a predominant phase in all samples. Fortunately, clear transparent glass was obtained from the composition with no TiO2 addition. Heat treatment of this glass did not induce phase change, three aforementioned phases still present. Increasing heat treatment time promoted a higher of observed intensity of NaNbO3. But the NaNbO3 crystalline size was not significantly developed with time. The dielectric response of the NaNbO3 crystals in the glass-ceramics samples are influenced by presence of other crystalline phases.

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Interaction between gadolinia-doped ceria electrolyte and sealing glass–ceramics

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2015.01.020 ◽

2015 ◽

Vol 35 (7) ◽

pp. 2201-2207 ◽

Cited By ~ 7

Author(s):

Lihua Fang ◽

Qi Zhang ◽

Fen Lin ◽

Dian Tang ◽

Teng Zhang

Keyword(s):

Glass Ceramics ◽

Doped Ceria ◽

Sealing Glass ◽

Ceria Electrolyte

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Study on process development and property evaluation of sol-gel derived magnesia stabilized zirconia minispheres

Materials Science-Poland ◽

10.2478/s13536-013-0190-9 ◽

2014 ◽

Vol 32 (2) ◽

pp. 145-156 ◽

Cited By ~ 2

Author(s):

J. Judes ◽

V. Kamaraj

Keyword(s):

Mechanical Properties ◽

Process Development ◽

Sintering Temperature ◽

Sol Gel ◽

Processing Parameters ◽

Processing Technique ◽

Density Variation ◽

Phase Identification ◽

Stabilized Zirconia ◽

Grinding Media

AbstractIn order to overcome limitations in the processing parameters of powder compaction method, a novel processing technique based on sol-gel route has been developed to produce near-net-shaped prototype fine zirconia minispheres with required properties that could potentially be used as grinding media. Impact of magnesia concentration and sintering temperature on the final product has been analyzed in detail. Zirconia minispheres have been characterized to establish a correlation between physical, structural and mechanical properties. Sintering temperature, soaking period, heating rate and viscosity of the sol apparently influence the characteristics of the magnesia stabilized zirconia minispheres. The phase identification, density variation, chemical decomposition, functional group specification, surface area, porosity, shrinkage and microstructural features of the dried and sintered final product have been studied. It has been observed that magnesia content, sintering temperature, density and the grain size of the sintered minispheres have a significant impact on the mechanical properties of the final product.

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Characteristics of 45S5 Bioglass-Ceramics Using Natural Raw Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.506.174 ◽

2012 ◽

Vol 506 ◽

pp. 174-177

Author(s):

W. Leenakul ◽

N. Pisitpipathsin ◽

P. Kantha ◽

N. Tawichai ◽

S. Tigunta ◽

...

Keyword(s):

Raw Materials ◽

Glass Ceramics ◽

Treatment Temperature ◽

Phase Identification ◽

Bovine Bone ◽

In Vitro Test ◽

Phase Form ◽

Different Temperatures ◽

Optimum Heat

The aim of this work was to analyze the effect of using rice husk ash (RHA) and bovine bone as raw materials of glass-ceramics based on the SiO2-Na2O-CaO-P2O5system on their physical, mechanical properties and bioactivity. All of the investigated compositions were prepared by melting the glass mixtures at 1300°C for 3 h. The resulting glass samples were heated at different temperatures ranging from 600 to 1000°C with fixed dwell-time for 2 h for crystallization. Phase identification of the prepared glass ceramics was carried out by X-Ray diffraction (XRD) and scanning electron microscope (SEM) techniques. In addition, in vitro test was carried out in stimulated body fluid (SBF). Differential thermal analysis (DTA) showed that the glass transition occurred at 505°C and crystallization at 700°C. The main crystalline phase form in most glass ceramics is a sodium calcium silicate. The optimum heat treatment temperature, at which the maximum mechanical value (620 HV) could be obtained, is around 1000°C. After incubation in SBF for 7 days, all of the samples show good bioactivity in vitro, as evident by the formation of bone like apatite phase.

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