Effect of MgO/Al2O3 Ratio on Properties and Crystallization of Glass-Ceramics

2014 ◽  
Vol 1065-1069 ◽  
pp. 1879-1883
Author(s):  
Jun Jie Hou ◽  
Yan Bing Zong ◽  
Zhao Bo Liu ◽  
Da Qiang Cang
Keyword(s):  
Bending Strength ◽  
Raw Materials ◽  
Glass Ceramics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Slag Glass ◽  
Higher Temperature ◽  
Dta Curves ◽  
Furnace Slag ◽  
Crystallization Of Glass

Reduction electric furnace slag, quartz sand and soapstone were used as the raw materials for preparation of glass-ceramics according to their compositions and characteristics. Differential thermal analysis, X-ray diffraction, scanning electron microscopy were used to investigate the crystallization mechanism, microstructure and main mechanical properties of slag glass-ceramics with different mass ratios of MgO/Al2O3. The exothermic peaks of the DTA curves shift to higher temperature with the decrease of MgO/Al2O3ratio. And along with the decreasing of the MgO/Al2O3, the crystallization of the glass-ceramics also decreased. The bending strength can reach 153.09MPa when the MgO/Al2O3ratio is 3.03.

Structure Characterization of Sintered CaO-Al2O3-SiO2 Glass-Ceramic Reinforced with Spodumene

2013 ◽  
Vol 834-836 ◽  
pp. 309-314
Author(s):  
Zi Fan Xiao ◽  
Jin Shu Cheng ◽  
Jun Xie
Keyword(s):  
Glass Ceramic ◽  
Energy Dispersive Spectrometry ◽  
Crystal Size ◽  
Bending Strength ◽  
Glass Ceramics ◽  
Structure Characterization ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray

A glass-ceramic belonging to the CaO-Al2O3-SiO2(CAS) system with different composition of spodumene and doping the Li2O with amount between 0~2.5 % (mass fraction) were prepared by onestage heat treatment, under sintering and crystallization temperature at 1120 °C for two hours. In this paper, differential thermal analysis, X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry and bending strength test were employed to investigate the microstructure and properties of all samples. β-wollastonite crystals were identified as the major crystalline phases, and increasing Li2O was found to be benefit for the crystallization and tiny crystalline phases remelting, resulting in the content of major crystalline phases increased first and then decreased with increasing the expense of spodumene. Meanwhile, the crystal size can be positively related with the content of Li2O. The preferable admixed dosage of spodumene can be obtained, besides the strength of glass-ceramics can be more than 90 MPa.

scholarly journals Application of Isothermal and Isoperibolic Calorimetry to Assess the Effect of Zinc on Hydration of Cement Blended with Slag

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 2930 ◽  
Author(s):  
Šiler ◽  
Kolářová ◽  
Novotný ◽  
Másilko ◽  
Bednárek ◽  
...  
Keyword(s):  
Cement Hydration ◽  
Raw Materials ◽  
Isothermal Calorimetry ◽  
Real Life ◽  
Diffraction Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Isoperibolic Calorimetry ◽  
Poorly Soluble ◽  
Furnace Slag

This work deals with the influence of zinc on cement hydration. The amount of zinc in cement has increased over recent years. This is mainly due to the utilization of solid waste and tires, which are widely used as a fuel in a rotary kiln. Zinc can also be introduced to cement through such secondary raw materials as slag, due to increased recycling of galvanized materials. The aim of this work was to determine the effect of zinc on the hydration of Portland cement, blended with ground blast furnace slag (GBFS). This effect was studied by isothermal and isoperibolic calorimetry. Both calorimetry methods are suitable for measurements during the first days of hydration. Isoperibolic calorimetry monitors the hydration process in real-life conditions, while isothermal calorimetry does so at a defined chosen temperature. Zinc was added to the cement in the form of two soluble salts, namely Zn(NO3)2, ZnCl2, and a poorly soluble compound, ZnO. The concentration of added zinc was chosen to be 0.05, 0.1, 0.5, and 1mass percent. The amount of GBFS replacement was 15% of cement dosage. The newly formed hydration products were identified by X-ray diffraction method (XRD).

scholarly journals Mutual Influence of Special Components in Baotou Steel Blast Furnace Slag on the Crystallization Behavior of Glass

2012 ◽  
Vol 2012 ◽  
pp. 1-6
Author(s):  
Yici Wang ◽  
Qi Jiang ◽  
Guoping Luo ◽  
Wenwu Yu ◽  
Yan Ban
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Crystallization Behavior ◽  
Mutual Influence ◽  
Raw Materials ◽  
Glass Ceramics ◽  
Nucleating Agent ◽  
Crystal Phase ◽  
Furnace Slag ◽  
Crystallization Of Glass

In the process of glass-ceramics prepared with Baotou steel blast furnace slag, quartz sand, and other raw materials by melting method, the mutual influence of the special components such as CaF2, REXOY, TiO2, K2O, and Na2O in the blast furnace slag on the crystallization behavior of parent glass was investigated using differential thermal analysis (DTA) and X-ray diffraction (XRD). The results show that the special components in slag can reduce the crystallization temperature and promote crystallization of glass phase, which belongs to surface crystallization of glass, and they cannot play the role of the nucleating agent; the major crystal phase composed of diopside, diopside containing aluminum and anorthite, is slightly different from the expected main crystal phase of diopside. Therefore, the nucleating agents of proper species and quantity must be added into the raw materials in order to obtain glass-ceramics. The results have important theoretical guidance meaning for realizing industrial production of Baotou steel blast furnace slag glass-ceramics preparation.

Preparation of A14SiC4 by Solid-State Reaction

2011 ◽  
Vol 399-401 ◽  
pp. 817-821
Author(s):  
Xiao Hong Liu ◽  
Hui Wang ◽  
Ling Ke Zeng ◽  
Cheng Ji Deng
Keyword(s):  
Carbon Black ◽  
Raw Materials ◽  
Heating Temperature ◽  
Argon Atmosphere ◽  
Mass Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Higher Temperature ◽  
Flake Structure ◽  
Scanning Electron

In this paper, A14SiC4 was synthesized by using flint, aluminum and carbon black as raw materials，and they mass ratio was 28:50:22. The samples were fired at 1500°C、1600°C and 1700°C in an argon atmosphere. The phase compositions were determined by X-ray diffraction (XRD), the microstructures were examined by scanning electron microscope (SEM) and the elemental and quantitative compositions were determined by the energy dispersive X-ray spectroscopy (EDX). The results showed that the flint reacted with the carbon black, and produced Al2O3 and SiC firstly; meanwhile Al4C3 as intermediate product formed by the reaction between Al and C. Then a certain Al4C3 reacted with SiC, and produced A14SiC4; most Al4C3 reacted with the Al2O3, and produced Al4O4C at higher temperature. Subsequently, the Al4O4C and the SiC reacted with carbon black, and produced A14SiC4. The formed quantity of A14SiC4 increased as the heating temperature was raised, and crystal structure was the flake structure of 1-2μm thickness and about 10μm length. The formation mechanism of A14SiC4 was also discussed.

Development and Characterization of Cementing Composites with Blast Furnace Slag Replacement

2014 ◽  
Vol 976 ◽  
pp. 246-250
Author(s):  
Reyna Sánchez-Ramírez ◽  
Manuela Diaz-Cruz ◽  
Sebastían Díaz de La Torre ◽  
Enrique Rocha-Rangel
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Bending Strength ◽  
Isothermal Calorimetry ◽  
Oil Wells ◽  
X Ray Diffraction ◽  
Hydration Kinetics ◽  
X Ray ◽  
Furnace Slag

In this work, they were produced and characterized cementing composites made with blast furnace slag replacement, for their use in the construction of oil wells. To this, slurries were prepared with a replacement of 20 and 30% slag, as well as a slurry with 100 % slag and a slurry with 100% H-cement were prepared. Starting materials were characterized by chemical analysis, X-ray diffraction and Fourier Transformed Infra Red. Slurries also were activated with sodium silicate in order to study theirs hydration kinetics, driving by isothermal calorimetry. These studies were complemented by the preparation of specimens of 4 X 4 X 16 cm to which they determine its compressive and bending strength during 2 and 28 days of curing. From the results it can be concluded that it was obtained a product that can be effectively used in the construction of oil wells.

scholarly journals Effect of Al2O3/SiO2 on the structure and properties of blast furnace slag glass-ceramics

2020 ◽  
Author(s):  
Zuhao Li ◽  
Feng He ◽  
Wentao Zhang ◽  
Junlin Xie
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Bending Strength ◽  
Glass Ceramics ◽  
Glass Network ◽  
Volume Density ◽  
Mas Nmr ◽  
Structure And Properties ◽  
Slag Glass ◽  
Furnace Slag

Abstract Different Al2O3/SiO2 glass-ceramics were prepared from blast furnace slag by traditional sintering method. The structure and properties of glasses or glass-ceramics were investigated by DSC, XRD, SEM, FTIR, 27Al MAS NMR. The DSC results showed that with the increase of Al2O3/SiO2, the glass transition temperature (Tg) first increased and then decreased, reached the minimum when Al2O3/SiO2 was 0.34. The volume density, bending strength and microhardness of glass-ceramics also showed the same variation rule. The FTIR and 27Al MAS NMR spectra results revealed this phenomenon. When Al2O3/SiO2 was 0.19, a large amount of Si4+ was added to the glass network to make the structure dense. With Al2O3/SiO2 increased from 0.24 to 0.34, the amount of [AlO6] in the glass increased while [AlO4] decreased, and the degree of network polymerization of the glass decreased; as Al2O3/SiO2 further increased from 0.34 to 0.39, [AlO4] increased and [AlO6] decreased in the glass, and the degree of network polymerization of the glass increased. The XRD results showed that the crystal phase of the glass-ceramics was composed of gehlenite, diopside and hyalophane. Moreover, with the increase of Al2O3/SiO2, the gehlenite content in the glass-ceramics increased, while the content of diopside and hyalophane decreased.

Effect of CaO/SiO2 Ratio and TiO2 on Glass-Ceramics Made from Steel Slag and Fly Ash

2012 ◽  
Vol 217-219 ◽  
pp. 119-123 ◽  
Author(s):  
Bao Wei Li ◽  
Hua Chen ◽  
Ming Zhao ◽  
Xue Feng Zhang ◽  
Yong Sheng Du ◽  
...  
Keyword(s):  
Fly Ash ◽  
Bending Strength ◽  
Steel Slag ◽  
Glass Ceramics ◽  
Nucleating Agent ◽  
Spherical Particles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Main Crystalline Phase ◽  
Average Size

Glass ceramics of the CaO-MgO-Al2O3-SiO2 system were fabricated by adopting the melting-casting procedure. Steel slag and fly ash were used as the major starting materials. The influence of CaO/SiO2 Ratio variations on the microstructure and mechanical properties were investigated using X-ray diffraction, scanning electron microscopy and property measurements. Augite is identified as the main crystalline phase of the as studied glass ceramics. The average size of augite grains in form of spherical particles is found within the range of 100-250nm. The bending strength of the glass-ceramics could reach as high as 170.74MPa. Increasing CaO/SiO2 show a beneficial influence on the crystallization of glass ceramics, and its effectiveness is inferior compared with that of increasing addition of nucleating agent, TiO2.

The Occurrence of Special Components in Blast Furnace Slag of Baotou Iron and Steel Company

2012 ◽  
Vol 220-223 ◽  
pp. 117-122
Author(s):  
Guo Ping Luo ◽  
Yan Ban ◽  
Yi Ci Wang ◽  
Wen Wu Yu ◽  
Qi Jiang
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Glass Ceramics ◽  
Optical Microscope ◽  
Aluminum Silicate ◽  
X Ray Diffraction ◽  
Silicate Mineral ◽  
Iron And Steel ◽  
X Ray ◽  
Furnace Slag

The mineral composition of the solidified blast furnace slag and the occurrence of special components CaF2, K2O, Na2O, RexOy and ThO2 were researched by optical microscope analysis, X-ray diffraction analysis and scanning electron microscopy and energy spectrum analysis. The results showed that the major minerals in solidified furnace slag are akermanite and gehlenite; the special component CaF2 is not hosted in the cuspidine (3CaO•2SiO2•CaF2), but in the magnesium and aluminum silicate mineral; the special components K2O，Na2O is hosted in akermanite, magnesium and aluminum silicate mineral and perovskite; the element thorium cannot form an independent mineral, but coexist with the rare earth element Ce in the perovskite. The results will lay a foundation for further study on the influence of these special components on the crystallization behavior of glass-ceramics.

Use of Angang Slag for the Production of Glass-Ceramic Materials

2008 ◽  
Vol 368-372 ◽  
pp. 1426-1428
Author(s):  
Hong Xia Lu ◽  
Tie Cui Hou ◽  
Zhang Wei ◽  
Li Jian Li ◽  
Rui Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Glass Ceramics ◽  
Ceramic Materials ◽  
Clay Brick ◽  
X Ray Diffraction ◽  
X Ray ◽  
Glass Ceramic Materials ◽  
Furnace Slag

The characteristic of Angang blast furnace slag was studied by X-ray fluorescence spectrometry, DSC, X-ray diffraction and SEM. SiO2-Al2O3-CaO system glass-ceramics have been obtained successfully from slag with other additives. The properties of slag-based glass-ceramics were analyzed in this paper. It has been found that nucleation temperature is in the range of 600~700 °C, and crystallization temperature is in the range of 850~950 °C. The crystals phase is 2 CaO⋅ Al2O3⋅ SiO2. The chemical and mechanical properties of slag-based glass-ceramics are superior to the properties of clay brick.

Effects of Phosphorus and Fluorine on the Crystallization and Structure of CaO-A12O3-SiO2 System Glass-Ceramic

2008 ◽  
Vol 368-372 ◽  
pp. 1412-1414 ◽  
Author(s):  
Jin Shu Cheng ◽  
Hui Guang Qiu ◽  
Hong Li ◽  
Jun Xie
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Glass Ceramic ◽  
Glass Ceramics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Yellow Phosphorus ◽  
Crystallization Of Glass ◽  
Scanning Electron

CaO-A12O3-SiO2 (CAS) system glass-ceramics were prepared by sintering with certain amount of yellow phosphorus slag. The effects of phosphorus and fluorine on the nucleation, crystallization and structure of CAS system glass-ceramics were investigated by differential thermal analysis, X-ray diffraction, scanning electron microscopy and other measuring methods. Glass-ceramics of CAS system with 42.32wt% yellow phosphorus slag were obtained by nucleating at 615°C for 1 hour and crystallizing at 926°C for 2 hours. The results showed that the introduction of phosphorus and fluorine promoted the nucleation and crystallization of glass-ceramics, lowering the crystallizing temperature. The main crystal phase of glass-ceramics was β-wollastonite. The density of the glass-ceramic was 2.695g/cm3.

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