Sintering and Crystallization of Glass-Ceramics for Optical Fiber Ferrule

2007 ◽  
Vol 336-338 ◽  
pp. 1840-1842
Author(s):  
Y.M. Zhu ◽  
Xia Wan Wu ◽  
Zhi Hong Li
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Glass Powder ◽  
Treatment Time ◽  
Glass Ceramics ◽  
Treatment Temperature ◽  
Residual Glass ◽  
Sio2 Glass ◽  
Powder Compacts ◽  
Crystallization Of Glass

The crystallization and sintering of the Li2O-Al2O3-SiO2 glass powder compacts were studied. Results showed the relative densities of the sintered compacts with lower crystallization temperatures were higher than those with higher crystallization temperatures. A small amount of residual glass in the crystallized compact was good for sintering and densification. Compared with the heat treatment time, the heat treatment temperature was an important factor for the crystallization and sintering of glass powder compacts. The crystallized compacts with a small amount of residual glass should be sintered at a relatively higher heating rate under the prerequisite of keeping sintered compacts from deformation.

Bulk Crystallization of Ceramic Whiskers from Borate-Based Glass

2012 ◽  
Vol 488-489 ◽  
pp. 291-294
Author(s):  
P. Sooksaen ◽  
S. Kannasute ◽  
K. Larbmark ◽  
C. Maneelada
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Glass Matrix ◽  
Surface Hardness ◽  
Glass Ceramics ◽  
Phase Evolution ◽  
Treatment Temperature ◽  
Residual Glass ◽  
Bulk Crystallization ◽  
Hardness Tester

Bulk crystallization of B2O3-SiO2-Al2O3-BaO-MgO glass system was investigated. Controlled heat treatment process was carried out between 900 and 1200°C to form glass-ceramics. Phase evolution in the crystallized glasses was studied by X-ray diffraction. Microstructures of the chemically etched surfaces were revealed by scanning electron microscope and micro-hardness was measured by Vickers hardness tester. High aspect ratio of aluminium borate whiskers were in the nano to micro regime and dispersed within the residual glass matrix. Whiskers had different sizes and compositions depending on the heat treatment temperature, which affected the surface hardness of the glass-ceramics. In general, increasing heat treatment temperature led to an increase in crystal size and length as well as the surface hardness (4.8 to 5.5 GPa). The whisker crystals oriented uniformly within the residual glass matrix leading to interlocking microstructure. The synthesized glass-ceramics in this study can be applied as machinable materials in various industries because their microstructures can resist microcracking and hence increase fracture toughness.

Lead titanate glass-ceramics derived from a silicate-based melt

2005 ◽  
Vol 20 (5) ◽  
pp. 1316-1323 ◽  
Author(s):  
P. Sooksaen ◽  
I.M. Reaney ◽  
D.C. Sinclair
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Crystal Size ◽  
Finite Size ◽  
Glass Ceramics ◽  
Treatment Temperature ◽  
Finite Size Effects ◽  
Peak Broadening ◽  
Permittivity Measurements ◽  
Nano Size

Glass composition 39PbO–1BaO–25TiO2–9.8Al2O3–24.2SiO2–1B2O3 (mol%) crystallized on heat treatment at ≥600 °C to form glass-ceramics whose majority phase was PbTiO3 (PT). At 600 °C, nano-size PT crystals (∼20–50 nm) with a c/a ratio of 1.000(1) were observed, but as heat-treatment temperature increased to 1000 °C, the crystal size and c/a ratio increased to ∼1.2 μm and 1.056(4), respectively. Permittivity measurements as a function of temperature revealed a broad peak at ∼400 °C associated with the nanocrystalline PT crystals, but it sharpened and increased in temperature as heat treatment temperature increased to 1000 °C. The causes of peak broadening and shift of Tc are believed to be due to either clamping of PT crystals by glass matrix, finite size effects due to their intrinsically small size, or the incorporation of dopant impurities such as Al, Si, or Ba ions in the PT phase.

Low-temperature thermal pretreatment process for recycling inner core of spent lithium iron phosphate batteries

2020 ◽  
pp. 0734242X2095740
Author(s):  
Haijun Bi ◽  
Huabing Zhu ◽  
Lei Zu ◽  
Yong Gao ◽  
Song Gao ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Low Temperature ◽  
Heat Treatment Temperature ◽  
Lithium Iron Phosphate ◽  
Inner Core ◽  
Treatment Time ◽  
Iron Phosphate ◽  
Treatment Temperature ◽  
Heat Treatment Time ◽  
Physicochemical Changes

Spent lithium iron phosphate (LFP) batteries contain abundant strategic lithium resources and are thus considered attractive secondary lithium sources. However, these batteries may contaminate the environment because they contain hazardous materials. In this work, a novel process involving low-temperature heat treatment is used as an alternative pretreatment method for recycling spent LFP batteries. When the temperature reaches 300°C, the dissociation effect of the anode material gradually improves with heat treatment time. At the heat treatment time of 120 minutes, an electrode material can be dissociated. The extension of heat treatment time has a minimal effect on quality loss. The physicochemical changes in thermally treated solid cathode and anode materials are examined through scanning electron microscopy with energy-dispersive X-ray spectroscopy. The heat treatment results in the complete separation of the materials from aluminium foil without contamination. The change in heat treatment temperature has a small effect on the quality of LFP material shedding. When the heat treatment temperature reaches 300°C and the time reaches 120 minutes, heat treatment time increases, and the yield of each particle size is stable and basically unchanged. The method can be scaled up and may reduce environmental pollution due to waste LFP batteries.

Microstructure of Semi-Solid Extruded Copper Alloy after Heat Treatment

2019 ◽  
Vol 285 ◽  
pp. 146-152
Author(s):  
Nai Yong Li ◽  
Han Xiao ◽  
Chi Xiong ◽  
De Hong Lu ◽  
Rong Feng Zhou
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Copper Alloy ◽  
Treatment Time ◽  
Solid Phase ◽  
Treatment Temperature ◽  
Primary Phase ◽  
Holding Time ◽  
Average Grain Size ◽  
Semi Solid

The semi-solid extruded ZCuSn10P1 copper alloy were annealed at different temperatures and time. The influences of heat treatment temperature and holding time on the microstructure of semi-solid ZCuSn10P1 copper alloy were investigated. The results show that with the increase of heat treatment temperature, the morphology of the semi-solid microstructure was improved, the sharp angle around the primary phase α-Cu and the liquid droplets were reduced. With the increase of heat treatment time, the solid-liquid segregation of the semi-solid structure was improved. The average grain size of the solid phase increased with the increasing of the holding time. After heat treatment, the solid solubility of the primary phase α-Cu increased, and the Sn and P elements in the liquid phase continued to diffuse to the primary phase α-Cu. The microstructure of semi-solid copper alloy was the most uniform after heat treatment at 350°C for 120 min.

Effect of Heat Treatment on the Reactivity and Crystallinity of Coal-Char

2005 ◽  
Author(s):  
Shouyu Zhang ◽  
Junfu Lu ◽  
Jianmin Zhang ◽  
Qing Liu ◽  
Guangxi Yue
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Treatment Time ◽  
Treatment Temperature ◽  
Coal Char ◽  
Heat Treatment Time ◽  
Heat Treat ◽  
Heat Treated ◽  
Layer Stacking ◽  
Crystalline Growth

The effect of heat treatment on the reactivity and crystallinity of char prepared from the vitrinite of two coals (YX, JJ) was investigated by using XRD and TGA in this paper. The results from TGA show that the reactivity of the chars from YXV and JJV decreases with the increase of heat treatment temperature. The reactivity of YXV char decreases quickly and significantly as heat treatment time increases. However, after heat treatment time of 60 min, it decreases slowly. The effect of heat treatment time on the reactivity of JJV char is small. The results from XRD show that the crystallinity of coal-char is determined by the intensity of heat treatment. When heat treatment time is more than 60 minutes, the turbostratic crystallite of YXV char prepared under 900°C changes remarkably and becomes more orderly. The aromatic layer stacking heights (Lc) of YXV Char when heat treated above 900°C increased with the increase of heat treatment time. The effect of heat treat time on Lc of JJV char is small, but under heat treatment temperature of 1200°C, the crystalline of JJV char grows distinctly. There is a good parallel relationship between the crystalline growth and deactivation of the chars. It can be concluded that the growth of the crystalline is the main reason for the deactivation of coal-char.

Load TiO2 or TiO2-N on the Porous Carbon

2012 ◽  
Vol 512-515 ◽  
pp. 1686-1689
Author(s):  
Jie Chen ◽  
Le Fu Mei ◽  
Li Bing Liao
Keyword(s):  
Heat Treatment ◽  
Porous Carbon ◽  
Heat Treatment Temperature ◽  
Treatment Time ◽  
Sol Gel ◽  
Treatment Temperature ◽  
Heat Treatment Time ◽  
Sem Images ◽  
Soaking Time ◽  
Sol Gel Process

In this paper, porous carbon has been used to carry TiO2 and TiO2-N by a sol-gel process. The effect of soaking time, heat treatment temperature, and heat treatment time on the carrying efficiency have been studied. XRD experiments indicated that TiO2 and TiO2-N crystallized in anatase and rutile with the ratio of 3∶2. SEM images showed that island-like TiO2 and TiO2-N particles with diameters in the range of 1-5um, the biggest size is about 10um, were evenly coated on the surface of the porous carbon.

Diopside–Ca-Tschermak clinopyroxene based glass–ceramics processed via sintering and crystallization of glass powder compacts

2007 ◽  
Vol 27 (5) ◽  
pp. 2325-2331 ◽  
Author(s):  
A. Goel ◽  
D.U. Tulyaganov ◽  
S. Agathopoulos ◽  
M.J. Ribeiro ◽  
R.N. Basu ◽  
...  
Keyword(s):  
Glass Powder ◽  
Glass Ceramics ◽  
Powder Compacts ◽  
Crystallization Of Glass

scholarly journals Effect of heat treatment temperature to the crystal growth and optical performance of Mn3O4 doped α-Zn2SiO4 based glass-ceramics

2019 ◽  
Vol 15 ◽  
pp. 102569
Author(s):  
Mohd Hafiz Mohd Zaid ◽  
Khamirul Amin Matori ◽  
Sidek Hj Ab Aziz ◽  
Halimah Mohamed Kamari ◽  
Yap Wing Fen ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Crystal Growth ◽  
Heat Treatment Temperature ◽  
Glass Ceramics ◽  
Treatment Temperature ◽  
Optical Performance
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