scholarly journals Investigation on Structural and Optical Properties of Willemite Doped Mn2+Based Glass-Ceramics Prepared by Conventional Solid-State Method

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Nur Farhana Samsudin ◽  
Khamirul Amin Matori ◽  
Josephine Ying Chi Liew ◽  
Yap Wing Fen ◽  
Mohd Hafiz Mohd Zaid ◽  
...  
Keyword(s):  
Glass Ceramic ◽  
Glass Ceramics ◽  
Structural Evolution ◽  
Emission Spectra ◽  
Soda Lime ◽  
X Ray Diffraction ◽  
Glass Waste ◽  
Solid State Method ◽  
Ceramic Samples ◽  
Zno Crystal

Mn-doped willemite (Zn2SiO4:Mn2+) glass-ceramics derived from ZnO-SLS glass system were prepared by a conventional melt-quenching technique followed by a controlled crystallization step employing the heat treatment process. Soda lime silica (SLS) glass waste, ZnO, and MnO were used as sources of silicon, zinc, and manganese, respectively. The obtained glass-ceramic samples were characterized using the X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared (FTIR), UV-Visible (UV-Vis), and photoluminescence (PL) spectroscopy. The results of XRD revealed that ZnO crystal and willemite (β-Zn2SiO4) were presented as major embedded crystalline phases. This observation was consistent with the result of FESEM which showed the presence of irregularity in shape and size of willemite crystallites. FTIR spectroscopy exhibits the structural evolution of willemite based glass-ceramics. The optical band gap shows a decreasing trend as the Mn-doping content increased. Photoluminescent technique was applied to characterize the role of Mn2+ions when entering the willemite glass-ceramic structure. By measuring the excitation and emission spectra, the main emission peak of the glass-ceramic samples located at a wavelength of 585 nm after subjecting to 260 nm excitations. The following results indicate that the obtained glass-ceramics can be applied as phosphor materials.

scholarly journals Bone bonding ability of some borate bio-glasses and their corresponding glass-ceramic derivatives

2012 ◽  
Vol 6 (4) ◽  
pp. 183-192 ◽  
Author(s):  
Fatma Margha ◽  
Amr Abdelghany
Keyword(s):  
Heat Treatment ◽  
Fourier Transform ◽  
Glass Ceramic ◽  
Glass Composition ◽  
Glass Ceramics ◽  
Soda Lime ◽  
Phosphate Solution ◽  
Borate Glasses ◽  
X Ray Diffraction ◽  
X Ray

Ternary borate glasses from the system Na2O?CaO?B2O3 together with soda-lime-borate samples containing 5 wt.% of MgO, Al2O3, SiO2 or P2O5 were prepared. The obtained glasses were converted to their glass-ceramic derivatives by controlled heat treatment. X-ray diffraction was employed to investigate the separated crys?talline phases in glass-ceramics after heat treatment of the glassy samples. The glasses and corresponding glass-ceramics after immersion in water or diluted phosphate solution for extended times were characterized by the grain method (adopted by several authors and recommended by ASTM) and Fourier-transform infrared spectra to justify the formation of hydroxyapatite as an indication of the bone bonding ability. The influence of glass composition on bioactivity potential was discussed too.

scholarly journals Fabrication and Crystallization of ZnO-SLS Glass Derived Willemite Glass-Ceramics as a Potential Material for Optics Applications

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Mohd Hafiz Mohd Zaid ◽  
Khamirul Amin Matori ◽  
Sidek Hj. Abdul Aziz ◽  
Halimah Mohamed Kamari ◽  
Wan Mahmood Mat Yunus ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Glass Ceramic ◽  
Glass Ceramics ◽  
Structural Evolution ◽  
Linear Shrinkage ◽  
Treatment Temperature ◽  
Isothermal Heat Treatment ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zinc Orthosilicate

Willemite glass-ceramics were successfully derived from conventional melt-quench ZnO-SLS precursor glass by an isothermal heat treatment process. The effect of heat treatment temperatures on the physical properties was investigated by Archimedes principle and linear shrinkage. The generation of willemite crystal phase and morphology with increase in heat treatment temperature was examined by X-ray diffraction (XRD), Fourier transform infrared (FTIR), and field emission scanning electron microscopy (FESEM) techniques. X-ray diffraction revealed that the metastableβ-Zn2SiO4and thermodynamically stable zinc orthosilicateα-Zn2SiO4phases can be observed at temperatures above 700°C. The experimental results indicated that the density and shrinkage of the glass-ceramic vary with increasing the sintering temperature. FTIR studies showed that the structure of glass-ceramic consists of SiO2and ZnO4units and exhibits the structural evolution of willemite glass-ceramics. The characteristic of strong vibrational bands can be related to theSiO44-tetrahedron corresponding to reference spectra of willemite.

IN-VITRO BIOACTIVITY EVALUATION OF K2O-SUBSTITUTED Na2O-CaO-P2O5-SiO2 GLASS BIOCERAMICS

2018 ◽  
Vol 25 (05) ◽  
pp. 1850104
Author(s):  
REHANA ZIA ◽  
MADEEHA RIAZ ◽  
AYESHA ASGHAR ◽  
TOUSIF HUSSAIN
Keyword(s):  
Body Fluid ◽  
Glass Ceramics ◽  
Proper Function ◽  
Processing Temperature ◽  
In Vitro Bioactivity ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
X Ray ◽  
Ceramic Samples

In the present work, the effect of K2O/Na2O substitution on the bioactivity of Na2O-CaO-P2O5-SiO2 ceramics prepared by solid-state method was studied. Ceramics-based bioactive implants are economical; they require low processing temperature and are more bioactive when compared with glasses, glass ceramics and composites. K2O is known to control proper function of cells and stimulate bone formation process. The hydroxyapatite layer developed on the surface of samples after soaking in stimulated body fluid solution was studied by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and atomic absorption spectroscopy. The results showed an increase in the bioactivity of the samples as Na2O was partially replaced with K2O. The addition of K2O enhanced the apatite-forming ability of the ceramic samples and makes it suitable for filling defects and fracture in bones.

Crystallization Behavior of Ferroelectric Glass-Ceramics of the Na2O-Nb2O5-Al2O3-SiO2 System Contained TiO2

2009 ◽  
Vol 421-422 ◽  
pp. 189-192 ◽  
Author(s):  
Anuson Niyompan ◽  
Kanita Srisurat ◽  
Rungnapa Tipakontitikul
Keyword(s):  
Glass Ceramic ◽  
Crystallization Behavior ◽  
Volume Fraction ◽  
Treatment Time ◽  
Glass Ceramics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ceramic Samples ◽  
Alumino Silicate ◽  
Quenched Glass

The ferroelectric glass-ceramic of the composition Na2O-Nb2O5-Al2O3-SiO2 was prepared by controlling crystallization of the glass that added with small amount of TiO2. The effect of TiO2 content on crystallization behavior and the dielectric property were determined. X-ray diffraction studied indicated that NaNbO3, NaNbO8 and a compound of alkali alumino silicate composition were readily formed in the as-quenched glass as the product of phase separation. After treatment at 700oC for various times, NaNbO3 volume fraction was found to increase with time. Crystalline size of the NaNbO3 was lower than 300 nm and it was developed with treatment time. Presence of TiO2 had considerably effect on NaNbO3 volume fraction when treatment time shorter than 1.0 h. The dielectric response of the glass-ceramic samples was found to arise from all contributions of crystalline phases and glass matrix responds.

scholarly journals Zinc containing borate glasses and glass-ceramics: Search for biomedical applications

2014 ◽  
Vol 8 (4) ◽  
pp. 185-193 ◽  
Author(s):  
Amr Abdelghany ◽  
Fatema Elbatal ◽  
Hatem Elbatal
Keyword(s):  
Glass Ceramic ◽  
Corrosion Behaviour ◽  
Glass Ceramics ◽  
Soda Lime ◽  
Dissolution Mechanism ◽  
Borate Glasses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Before And After ◽  
Diffraction Patterns

Ternary soda lime borate glass and samples with ZnO replacing CaO up to 10mol%were prepared and studied for their bone bonding ability. Fourier transform infrared (FTIR) absorption spectra of the prepared glasses before and after immersion in simulated body fluid (SBF), for one or two weeks, showed the appearance of calcium phosphate (hydroxyapatite (HA)) which is an indication of bone bonding ability. X-ray diffraction patterns were measured for the glasses and indicated the presence of small peaks related to hydroxyapatite in the samples immersed in SBF. The glasses were heat treated with controlled two-step regime to convert them to their corresponding glass-ceramic derivatives. FTIR and X-ray diffraction measurements of the glass-ceramic samples (before and after immersion in SBF) confirmed the appearance of HA which is influenced by ZnO content. The overall data are explained on the basis of current views about the corrosion behaviour of borate glasses including hydrolysis and direct dissolution mechanism.

Effect of Gradual Substitution of CaO by SrO in Glass-Ceramic Materials of the System SiO2 - Al2O3 - CaF2 - RO (R = Ca, Mg, Sr)

2012 ◽  
Vol 1373 ◽  
Author(s):  
M. Garza-García ◽  
J. López-Cuevas ◽  
C.A. Gutiérrez-Chavarría ◽  
N. Piedad-Sánchez ◽  
E. Camporredondo-Saucedo ◽  
...  
Keyword(s):  
Glass Ceramic ◽  
Vickers Microhardness ◽  
Glass Ceramics ◽  
Ceramic Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Substitution Level ◽  
Glass Ceramic Materials ◽  
Ceramic Samples ◽  
Crystallization Fraction

ABSTRACTThe density, Vickers microhardness and crystallization fraction of glass-ceramic materials synthesized from parent glasses are determined in which CaO is gradually substituted by SrO. The chemical composition (in mol.%) of the parent glasses is 54SiO2-(23-X)CaO-12MgO-5Al2O3-6CaF2-XSrO, where X is the employed CaO substitution level (X = 0, 3, 6 and 9 mol.%, with X = 0 corresponding to the reference material). In order to determine the type of crystallization occurring in the glass-ceramic samples, as well as the crystalline phases formed in them, these are characterized by both Scanning Electron Microscopy (SEM/EDS) and X-Ray Diffraction (XRD). Independently of the CaO substitution level employed, the glass-ceramics show the formation of a solid solution corresponding to diopside-type pyroxene, with chemical formula Ca(Mg,Al)(Al,Si)2O6, as a single crystalline phase. The synthesized glass-ceramic materials with the reference composition show the highest Vickers microhardness and crystallization fraction, as well as the lowest density.

scholarly journals Crystallization Behavior and Microstructure of Bio Glass-Ceramic System

2013 ◽  
Vol 19 ◽  
pp. 58-68 ◽  
Author(s):  
Behzad Mehdikhani ◽  
Gholam Hossein Borhani
Keyword(s):  
Glass Ceramic ◽  
Crystallization Behavior ◽  
Glass Ceramics ◽  
Al2o3 Content ◽  
Sintering Behavior ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ceramic Samples ◽  
Molar Percent ◽  
Glass Compositions

The effects of Al2O3 on the crystallization behavior of glass compositions in the Na2O-CaO-SiO2 system were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Effect of Al2O3 content on the mechanical, density, phase formation and microstructures of Na2O-CaO–P2O5–Al2O3-SiO2 glass ceramics were studied. Thermal parameters of each glass were studied by DTA. The density of the glass ceramic samples was measured by Archimedes’ method. It was found that the glass–ceramic containing 2.0 molar percent Al2O3 had desirable sintering behavior and reached to an acceptable density. Phase investigation and micro structural study were performed by XRD and SEM, respectively.

Development of Glass-Ceramics from Soda Lime Silica Glass Waste by Direct Sintering Method for Opal Imitation

2017 ◽  
Vol 751 ◽  
pp. 397-402
Author(s):  
Duangkhae Bootkul ◽  
Sawet Intarasiri
Keyword(s):  
Silica Glass ◽  
Glass Ceramics ◽  
Soda Lime ◽  
X Ray Diffraction ◽  
Glass Waste ◽  
X Ray ◽  
Sintered Glass ◽  
Soda Lime Silica Glass ◽  
Common Opal

Natural opal, an amorphous, hydrous form of silica (SiO2-n-H2O), has been one of the favored precious gemstones for many centuries. Though beautiful, opal is very fragile and is damaged quite easily. Thus, opals of all varieties have been synthesized experimentally and commercially. The objective of this project was to synthesize and to compare crystalline opals. In this work, the development of powder sintered glass ceramics process based on soda lime silica glass waste with metal oxide powder enable jewelry applications. The substantial viscous flow of the glass led to dense products for rapid treatments at relatively low temperatures (900–1,000°C), whereas glass/metal powder interactions resulted in the formation of color agent crystals, provide enhancing optical properties. Several techniques were applied for characterization of the ingots. The chemical analysis was performed by Energy Dispersive X-ray Fluorescence (ED-XRF). The mineralogical compositions of the samples were determined by X-ray diffraction analysis. Raman spectroscopy was applied for optical characterization. The results were compared with a natural common opal. The present investigation demonstrated that the common opal with both color and colorless appearance can be synthesized by the technique, as the crystalline phase of opal structure was identified by XRD measurement. There is a great potential for such materials with novel functionalities for artificial gemstone application, i.e. opal forming.

scholarly journals Transformation Mechanism of Fluormica to Fluoramphibole in Fluoramphibole Glass Ceramics

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Wei Si ◽  
Hua-Shen Xu ◽  
Ming Sun ◽  
Chao Ding ◽  
Wei-Yi Zhang
Keyword(s):  
Glass Ceramics ◽  
Soda Lime ◽  
Relative Displacement ◽  
Soda Lime Glass ◽  
X Ray Diffraction ◽  
Isothermal Heating ◽  
Transformation Mechanism ◽  
Infrared Reflection ◽  
Bridge Oxygen ◽  
Powder Compacts

During isothermal sintering at 820°C, the transformation mechanism of fluormica to fluoramphibole in powder compacts of fluormica and soda-lime glass was investigated using differential thermal analysis, infrared reflection spectrometry, X-ray diffraction, scanning electron microscopy, and so forth. Results show that an interaction between fluormica and glass occurred during isothermal heating; O2−, Na+, and Ca2+ions were diffused from glass to fluormica. This diffusion facilitates the transformation of the sheet structures of fluormica crystals to double-chain structures by the breakage of bridge oxygen bonds in the sheet. Subsequently, the broken two parallel double chains were rearranged by relative displacement along thec-axis direction of the fluormica crystal and were linked by Na+and Ca2+ions to form fluoramphibole. A crystallography model of fluormica-fluoramphibole transformation was established in this study.

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