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Effect of different phosphate content towards the surface morphology formation, chemical bond, crystallization, phase and compressive strength of sintered sol-gel bio-glass
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Synthesis and characterization of zirconia filled sol-gel derived bio-glass for load-bearing bone implant material
No full textAccess is limited to UniMAP community.At present, clinical applications of bioactive glasses are only limited to
those materials synthesized by the melting process. Glass melting process required
high processing temperature which contributes to several weaknesses. Sol gel
glass shows relatively low toughness and low compressive strength to be used
especially in load bearing bone implant materials. Metal oxides, such as MgO,TiO2
and Al2O3 are added to glass to improve their physical-chemical properties. In this
study we are using zirconia as the oxide phase. Potential used of zirconia in
bioglass have not been widely studied. Its need more research and investigations
before can be commercialized and accepted usage in clinical applications. In this
study, we synthesized the SiO2 – CaO – P2O5 bioglass system using sol-gel method
and compared their mechanical properties with effect addition of zirconia and
different sintering temperature. The microstructure features resulting glass-zirconia
was characterize by Field emission Scanning Electron Microscopy (FeSEM),
Energy Dispersive Spectroscopy (EDS), Fourier transform infrared spectroscopy
(FTIR). Compressive strength is measured as mechanical properties. The result
showed that increasing the temperature improved the shrinkage percentage of
sample, the densification between the grains increase, the crystallization natural
amorphous can be observed, the bond between zirconia and gel glass are detected
and the phase obtain diffraction peak can confirmed the phase induced. The
addition of zirconia can reduced the shrinkage percentage of the sample, the pores
is reduced because filled by zirconia particles, the Silicon oxygen bond (Si-O-Si)
formed and the compressive strength is increased as the addition of zirconia
increased at both temperatures. Thus all the result supports the mechanical
properties of the gel glass increase by increasing the addition amount of zirconia
and increased sintering temperature
Synthesis of Cordierite ceramic using solid state reaction technique
No full textIn this project work, cordierite/ indialite phase was synthesized from three different
ratios of powder mixture involved of kaolin, talc and alumina powder. The weight ratios
of powder mixtures used in this project were 1:1:2, 1:1:3 and 2:2:5 which refers to alumina: talc: kaolin based on cordierite chemical composition. These powder mixtures
were milled for two different milling time which are 6 h and 12 h using a planetary ball
mill. Then the powder mixtures were sintered at 1400°C with two different soaking times 3 h and 6 h using high temperature muffle furnace. Sintered samples of the powder mixture were characterized by X-ray diffraction (XRD) and Scanning Electron
Microscope (SEM). The XRD analysis showed α-cordierite (indialite) as a major phase
existed in the samples milled for 6 h which sintered at 1400°C for 6 h soaking time.
However, samples milled for 6 h sintered at 1400°C for 3 h soaking time the formation
of cordierite phase were not observed but only secondary phases were formed including
corundum, spinel, forsterite and cristobalite. Meanwhile, samples milled for 12 h sintered at the same temperature for 3 h and 6 h soaking time both showed α- cordierite (indialite) as a major phase existed. This experiment shows that, cordierite phase can be produced through simple milling and sintering method
The fabrication of porcelain ceramic via Wet casting technique
No full textPorcelain ceramic which composed of ball clay, kaolin, silica and feldspar were
fabricated and investigated to study the effect of sintering temperature on mechanical
properties. Two types of parameter were used in these projects which were different
composition of raw material and sintering temperature. Three different compositions of
raw materials were used which were composition A, B and C. The wet mixture then was sintered at 1200°C and 1300°C for 3 hours soaking time at 5°C/min for heating rate. The compression test and characterization of the sample such as the porosity, density, shrinkage and weight loss were carried out in order to determine the properties of the final product. The sample were also been analyzed using Scanning Electron Microscope (SEM) to capture the sample microstructure. From all experiment and testing, it is found that by increasing the sintering temperature, the compression strength, bulk density, and shrinkage were increased and at the same time reducing the percent of porosity of the porcelain ceramic
Fabrication and characterization of Ceramic Porcelain tiles
No full textFabrication of ceramic tiles requires detailed attention on the processing parameters such as raw material size and weight percentage, forming and drying process, and sintering temperature. The scope of the project is to study the final product properties with variation in the composition percentage and sintering temperature. This project employs hydraulic powder pressing as primary forming method of compound A, B and C where bar shaped green body was produced. Sintering were conducted in three different temperatures which were at 1200°C, 1300°C and 1400°C for 3 hours at heating rate 5°C/min. The resulting body then analyzed to study the final property of the compounds as function of sintering temperature. Morphology studies were conducted using image analyzer. Meanwhile, the mechanical and physical testing includes particle size analysis, density and porosity study, linear shrinkage study, energy dispersive spectrometry (SEM/EDX) analysis, and modulus of rupture and compression test were done. These analyses have provided the information that pores coarsening has occurred at 1300°C which in turn have produced low mechanical properties. From these studies, mostly all the samples has showed better physical and mechanical properties at 1200°C indicating that 1200°C as the optimum temperature for all the samples. This indicates the small variation of silica would change the properties of the tiles
Effect of sintering condition on the properties of Silicate ceramic materials
No full textThis study addresses the effects of fabrication techniques on the development of mechanical properties of sintered clay ceramics. The influence of thermal treatment, soaking time and firing temperature, were investigated in order to optimize the fabrication process and to obtain the enhanced mechanical properties. Single clay raw material such as kaolin, ball clay and silica were used for this study. Samples were uniaxially pressed in a rectangular shape and sintered to temperature ranging from 1000 °C to 1400 °C sintering temperature at various soaking time. The variation of flexural strength and compression strength starting from 1000 °C to 1400 °C temperature with heating rate 5 °C/min was also presented. In addition, the density, porosity and shrinkage of the sintered samples also have been determined. Mechanical properties characterization was performed by means of three-point bending tests and compression test. The sample were also been analyzed using Scanning Electron Microscope (SEM) to observe the microstructure of the sample. From all experiment and testing, it is found that by increasing of sintering temperature will decreased the percent of porosity in ceramic sintered sample and at the same the same time increased the bulk density and flexural strength of the ceramic sample. In this study, the results proved that high soaking time in the early stage of firing has influence on densification and the resulting mechanical properties of ceramic materials
Synthesis and characterization of ternary glass composition derived by sol-gel method
No full textAccess is limited to UniMAP community.This study was conducted in order to investigate the effect of different Si/Ca ratio (reduced in CaO content) to the properties of ternary glass (SiO2-CaO-P2O5). The glass powder with Si/Ca ratio of 50:45, 70:25 and 90:5 was synthesized by sol-gel method, compacted into pellets and finally sintered at 700°C. The increase in amount of CaO which act as network modifier in the glass system was figured out whether it influenced the physical, structural and bioactivity properties of bioglass. The physical, structural and bioactivity properties of these glasses were observed by using Archimedes test, XRF, BET, XRD, FTIR, SEM-EDX, and Pycnometer. Furthermore, glass pellet was immersed in the SBF solutions for 7 days and their in vitro bioactivity were evaluated. Basically, all compositions showed different level of bioactivity in SBF solutions and glass with the highest CaO content (Si:Ca = 50:45) showed the highest formation of carbonated apatite on its surface. As a conclusion, higher CaO content leads to the higher formation of non-bridging oxygen atom, higher crystalline calcium phosphate and reduced the silicate glass structural bonding which attributed to the increased in apatite forming ability of the glass
Preparation and properties of porous calcium phosphate
Get PDFLink to publisher's homepage at http://jere.unimap.edu.myIn this study, preparation of porous calcium phosphate was involved the addition of sodium di-hydrogen phosphate, NaH2PO4 and di-sodium hydrogen phosphate, Na2HPO4 into the raw calcium phosphate powder. The sodium hydrogen phosphates salt was act as the porosity agent for the bio-ceramic samples preparation. This method using sodium phosphates salt produced samples with 20-70% porosities. After sintering the sample above 700°C with 4 hours soaking time, results showed that open-pores structure in the range of 1 to 400μm in size were obtained. The pores structure and sizes were depending on the percent addition of the additive and the level of sintering temperature. The compressive strength of porous samples was approximately ranging between 14.38 to 103.42 MPa
Sol-gel synthesis and preliminary characterizations of novel silica hybrid xerogels
No full textLink to publisher's homepage at http://www.ttp.net/Hybrid silica xerogel mesoporous composite was synthesized by a mild temperature acid catalysed sol-gel route where a natural copolymer; sodium alginate (Na-COOH) together with calcium oxide (CaO) powder were incorporated into silica sol precursor prior to gel formation. For this study, bulk xerogels samples were prepared with the amount of silica precursor and the natural copolymer was fixed meanwhile the loading of calcium oxide was varied at 10 and 20 wt%. The monolith silica was also synthesized as control parameter. The preliminary properties were investigated using XRD, FTIR and SEM together with EDS for elemental analysis. The calcium oxide powder used in this study was prepared from calcium hydroxide, CaOH compound, which was previously calcined at 1000°C for 3 hours in normal air. The component of calcium oxide and sodium alginate were found to be uniformly dispersed in matrixes without affecting the cross-linked silica formation. As the presence of the components in the silica matrixes, the synthesized hybrid xerogels were found to be crack-free, structurally amorphous and physically opaque. Furthermore, the hybrid xerogels samples were found to have denser bodies, smoother surface, and decreased in particle sizes and thus might produced less brittleness in nature compared to the monolith xerogels
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