Crystallisation of processed nepheline syenite–magnesite glasses

Hamzawy, Esmat M. A.; Khater, G.A.

doi:10.1179/174367606x69870

Cited by 11 publications

(14 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, the residual glass would be located in the region of formation of gehlenite phase, which is a silicate belonging to the melilite group. Concerning to augite (pyroxene group) devitrification, several studies have shown that the incorporation of TiO 2 in the base glass not only facilitates early devitrification but it also enhances the development of crystalline phases belonging to the pyroxene group [17]. Both melilite and augite are common crystalline phases in glass ceramics prepared from wastes vitrification [23][24][25][26] and basalt glasses [27] and they lead to glass-ceramics with potential application in the building material industry [28].…”

Section: Discussionmentioning

confidence: 99%

Crystallisation of nepheline-based glass frits through fast-firing process

Guzmán-Carrillo

Pérez

Romero

2017

Journal of Non-Crystalline Solids

View full text Add to dashboard Cite

The aim of this research was to study the feasibility of producing sintered nepheline glass-ceramic through a fast firing route. The thermal behaviour of the original glass was analyzed by mean of differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). The microstructural analysis of glass-ceramic materials was carried out by field-emission scanning electron microscopy (FE-SEM). The results showed that the studied wastes are able to produce a glass and glass-ceramic materials through a sinter-crystallization process, 100 µm being the critical glass particle size.Glass-ceramics are composed of residual glassy phase and crystalline phases such as nepheline (NaAlSiO 4 ), augite (Ca, Na)(Mg, Fe, Al)( Si, Al) 2 O 4 and a solid solution belonging to the melilite group (Ca, Na)(Al, Mg, Fe,)( Si, Al) 2 O 7 . In a first evaluation, water absorption (0.02%) and bending strength (71MPa) of glass-ceramic achieved after thermal treatment at 1100ºC/5min suggest that sintered glass-ceramics can be easily produced from coal fly ash and metallurgical slag wastes by a fast-firing cycle and they are extremely serviceable for outdoor flooring and wall cladding.

show abstract

Section: Discussionmentioning

confidence: 99%

Crystallisation of nepheline-based glass frits through fast-firing process

Guzmán-Carrillo

Pérez

Romero

2017

Journal of Non-Crystalline Solids

View full text Add to dashboard Cite

show abstract

“…This behaviour indicates that the devitrification process of RHA glass will primarily occur through a surface crystallization mechanism. Normally, nepheline glass-ceramics are produced by controlled heat treatments in two steps (nucleation and crystal growth) from bulk glasses whose composition includes nucleating agents as TiO 2 [33,34]. If this surface crystallization mechanism will be confirmed, glass-ceramics at lower temperatures and without the use of nucleating agent could be obtained through a sintering route.…”

Section: Resultsmentioning

confidence: 99%

Thermal approach to evaluate the sintering–crystallization ability in a nepheline–forsterite-based glass-ceramics

Andreola

Barbieri

Lancellotti

et al. 2015

J Therm Anal Calorim

View full text Add to dashboard Cite

A glass in the SiO 2 -Al 2 O 3 -MgO-Na 2 O system was formulated using a non-conventional silica source and other pure raw materials. The thermal stability and crystallization mechanism have been studied by means of differential scanning calorimetry (DSC). Besides, the glass ability to sintering-crystallization has been examined by optical dilatometry, a non-contact technique allowing the acquisition of dilatometric data in the viscoelastic temperature region. The experimental data were confirmed with theoretical equations. X-ray diffraction and field emission scanning electron microscopy were used to verify the crystallization study and electron scanning microscopy to examine the fired sample microstructures. The prevalent crystallization mechanism has been evaluated from different parameters derived from characteristic temperatures of non-isothermal DSC curves, namely the working range (DT TS ), reduced glass transition temperature (T gr ), and the dissimilarity in crystallization temperature (DT p ) between fine (\63 lm) and coarse (fragment) glass samples.

show abstract

“…Researchers have been mostly focused on glass in systems like SiO2-Al2O3 , MgO-Al2O3-SiO2, and CaO-Al2O3-SiO2 [5]. In order to avoid uncontrolled crystallizing, controlled surface crystallizing has been performed on glasses in systems MgO-Al2O3-SiO2 and CaO-Al2O3-SiO2 [6]. The basic phases of crystalline have been found to be anorthite (CaAl2Si2O8), titanite (CaTiSiO5), wollastonite (CaSiO3), spinel (MgAl2O4) forsterite (Mg2SiO4), and cordierite ((Mg, Fe)2Al4Si5O18), [6].…”

Section: Introductionmentioning

confidence: 99%

“…In order to avoid uncontrolled crystallizing, controlled surface crystallizing has been performed on glasses in systems MgO-Al2O3-SiO2 and CaO-Al2O3-SiO2 [6]. The basic phases of crystalline have been found to be anorthite (CaAl2Si2O8), titanite (CaTiSiO5), wollastonite (CaSiO3), spinel (MgAl2O4) forsterite (Mg2SiO4), and cordierite ((Mg, Fe)2Al4Si5O18), [6]. Research on CaO-MgO-Al2O3-SiO2 system is significant as well in order to understand the reaction that occurs in the rocks, MgO refractories, and blast furnace slag [7].…”

Section: Introductionmentioning

confidence: 99%

Use of Bypass Cement Dust from Al-Kufa Cement Factory for Production of Glass Ceramic Material

Abid¹,

Yasse

Saleh

2019

QJES

View full text Add to dashboard Cite

Glass ceramicMain material Reinforcing materialsSintering process A B S T R A C T Bypass cement dust was supplied from the Alkufa cement factory, which has been used in preparing glass ceramic material. The percentage of bypass cement dust, which is included in the overall batch, is about 30 wt %. The bypass cement dust composition has been modified by adding other materials like marble, granite, and silica, to prepare glass ceramic material by powder technology. The prepared samples with different ratios ingredients were pressed under a load of 15 tons/cm 2 for 90 sec, in a steel mold of 30 mm in diameter, liquid phase sintering is carried out by using High-Temperature Furnace at 100 -1250 º C and 208/240 VAC. Techniques including SEM (Scanning electron microscopy) and XRD (X-ray diffraction) tests were then used to evaluate the produced material. The obtained glass ceramic material has high bulk and apparent density, low apparent porosity, high compression strength and hardness , low electrical and thermal conductivity. The XRD and SEM results showed that glass ceramic materials are formed. The phase transformation has happened and the titanite, wollastonite, diopside, periclase, and silica condense clusters phase are formed, which are the important phases of glass ceramic. Tests show that the sample A5 contains 38% bypass cement dust, 30%granite, and 32% silica; and the sample C5 contains 28% bypass, granite 30%, marble 10%, and silica 32%; and the sample B4 contains 59% bypass, 25% marble, and 16% silica. Showing properties A5 and C5 which conform to that of glass ceramic properties better than B4. The research is considered a pioneer work in the field of investment of dust of bypass cement for producing glass ceramic materials. It represents an important step and could be the basis for future researches leading to the achievement of glass ceramic production in Iraq.

show abstract

Crystallisation of processed nepheline syenite–magnesite glasses

Cited by 11 publications

References 10 publications

Crystallisation of nepheline-based glass frits through fast-firing process

Crystallisation of nepheline-based glass frits through fast-firing process

Thermal approach to evaluate the sintering–crystallization ability in a nepheline–forsterite-based glass-ceramics

Use of Bypass Cement Dust from Al-Kufa Cement Factory for Production of Glass Ceramic Material

Contact Info

Product

Resources

About