Pressure assisted sintering of Al2O3–Y2O3 glass microspheres: sintering conditions, grain size, and mechanical properties of sintered ceramics

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Anna Prnová ◽  
Jana Valúchová ◽  
Monika Michálková ◽  
Beáta Pecušová ◽  
Milan Parchovianský ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Hot Pressing ◽  
Pechini Method ◽  
Sol Gel ◽  
Applied Pressure ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Glass Microspheres ◽  
Amorphous Powders

Abstract Glass microspheres with yttria-alumina eutectic composition (76.8 mol % Al2O3 and 23.2 mol % Y2O3) were prepared by sol-gel Pechini method and flame synthesis with or without subsequent milling. Prepared amorphous powders were studied by X-ray powder diffraction (XRD), particle size analysis (PSA), scanning electron microscopy (SEM) and differential thermal analysis (DTA). Hot pressing (HP), rapid hot pressing (RHP) and spark plasma sintering (SPS) were used to sinter amorphous precursor powders at 1600 °C without holding time (0 min). The preparation process including milling step resulted in amorphous powders with narrower particle size distribution and smaller particle size. All applied pressure assisted sintering techniques resulted in dense bulk samples with fine grained microstructure consisting of irregular α-Al2O3 and Y3Al5O12 (YAG) grains. Milling was beneficial in terms of final microstructure refinement and mechanical properties of sintered materials. A material with the Vickers hardness of HV = (17.1 ± 0.3) GPa and indentation fracture resistance of (4.2 ± 0.2) MPa.m1/2 was prepared from the powder milled for 12 h.

The Influence of Aggregates on the Properties of Concrete

2014 ◽  
Vol 1000 ◽  
pp. 277-280 ◽  
Author(s):  
Pavel Šiler ◽  
Ondřej Bezděk ◽  
Iva Kolářová ◽  
Eva Bartoníčková ◽  
Tomáš Opravil ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Portland Cement ◽  
Particle Size Analysis ◽  
Hydration Process ◽  
Silica Sand ◽  
Size Analysis ◽  
Isoperibolic Calorimetry

This work is focused on the influence of aggregates on the mechanical properties of concrete and hydration process. The flexural strength and compressive strength were observed after 1, 7 and 28 days of curing. The process of hydration was monitored using isoperibolic calorimetry. Laser particle size analysis of aggregates was also performed. The following materials were used: Portland cement CEM I 42,5 R-Sc, finely ground silica sand, calcinated bauxite, fine, medium and rough testing sand (defined in ČSN EN 196-1).

scholarly journals Synthesis of ZnO-CdO Nanocomposites

2013 ◽  
Vol 1 (1) ◽  
pp. 11-14
Author(s):  
N. Sahu ◽  
◽  
R. K. Duchaniya ◽  
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Low Cost ◽  
Sol Gel ◽  
Particle Size Analysis ◽  
Synthesis Process ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

The ZnO-CdO nanocomposite was prepared by sol-gel method by using their respective nitrates. It is a simple and low cost method to prepare nanocomposites. The drying temperature and drying period of prepared gel was varied during the synthesis process. The prepared samples were characterized by using scanning electron microscope (SEM), particle size analysis (PSA), X-ray diffraction (XRD) and photoluminescence spectroscopy (PL) to get surface morphology, idea of getting particle of nanosized range so that further characterizations can be done, to study the optical property of synthesized nanocomposite and measure the band gap . The grain size determined by Scherrer’s formula was found to be between 30-50 nm.

Preparation and Characterization of Bone Cements Incorporated with Montmorillonite

2007 ◽  
Vol 342-343 ◽  
pp. 753-756
Author(s):  
Sun Yeon Lee ◽  
Sung Soo Kim
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Average Particle Size ◽  
Gel Permeation Chromatography ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Average Particle ◽  
Bone Cements ◽  
Liquid Component ◽  
Powder Component

Bone cements incorporated with montmorillonite (MMT) were prepared in an attempt to improve their mechanical properties. The cements were characterized using particle size analysis, gel permeation chromatography, viscosity measurements, X-ray diffraction, transmission electron microscopy, and mechanical properties. The average particle size and molecular weight of the PMMA powders used were 47 μm and 100,000 g/mol, respectively. The incorporation of MMT led to an increase in viscosity of the bone cement but did not severely affect its setting temperature or the amount of residual monomer. Regardless of the MMT mixing methods used, in this case MMT being mixing in liquid and powder components, sodium MMT (SMMT) was not well dispersed in the bone cements, which was believed to be due to its hydrophilicity. Organophilic MMT (OMMT) was better dispersed in the liquid component than in the powder component. The tensile and compressive strengths of the bone cements with 0.5 wt% OMMT mixed in the liquid component were 35.9 and 119.6 MPa, respectively, which were considerably higher than those of the bone cements with 0.5 wt% OMMT mixed in the powder component (27.9 and 100.5 MPa, respectively).

Production of Porous Bioactive Glass (13-93)/Poly Ethylene Glycol Composite Scaffold for Bone Tissue Defects

2021 ◽  
Vol 1039 ◽  
pp. 510-517
Author(s):  
Zainab I. Dhary ◽  
Saad B.H. Farid ◽  
Alaa A. Atiyah
Keyword(s):  
Particle Size ◽  
Bioactive Glass ◽  
Glass Powder ◽  
Composite Scaffold ◽  
Sol Gel ◽  
Particle Size Analysis ◽  
Mode Analysis ◽  
Size Analysis ◽  
Porous Scaffolds ◽  
Salt Leaching

Using the sol-gel process, glass powder was made. After the preparation method of the glass powder, x-ray analytical (XRD), particle size analysis and Fourier Transform Infrared (FTIR) were performed. The particle size analysis of manufactured glass (13-93) is found to be about 2.978 μm. (XRD) mode analysis suggested that the resulting porous scaffolds were amorphous. Using the process of salt leaching to create bioactive glass scaffolds (13-93) with structural and physical properties suitable for the human trabecular bone. XRD spectroscopy, scanning electron microscopy (SEM) and FTIR after sintering at temperature 750 °C were used to investigate the microstructure and chemical bonding of the porous scaffolds. The synthesized scaffold was soaked in medium of the simulated body fluid (SBF) and examined by SEM and XRD analysis in order to evaluate bioactivity. From the SEM morphology analysis results, it was noticed that the scaffolds comprised open and interconnected pores with a porosity range of 75-78%. High bioactivity of pours scaffolds was reported to have been observed after soaking 7days in SBF media because of the formation of apatite layer on its surfaces. Keywords: bioactive glass (13-93), scaffold, salt leaching method, SBF, sol-gel.

The Carbon Black Sonofication Effects on Vulcanisate Properties of Natural Rubber

2012 ◽  
Vol 626 ◽  
pp. 114-120 ◽  
Author(s):  
Mahendra Anggaravidya ◽  
Sudirman Sudirman ◽  
Bambang Soegijono ◽  
Emil Budianto ◽  
Martin Djamin
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Carbon Black ◽  
Natural Rubber ◽  
Carbon Black Particle ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Black Particle ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes

The mechanical properties of natural rubber can be enhanced by the addition of carbon black. The mechanical properties change is highly affected by particle size and carbon black structure used. A modification of N660 carbon black was conducted in the research by sonoficating the carbon black for 3 and 5 hours (N600-M3; M5). The results of adding modified carbon black were characterised by Particle Size Analysis (PSA), Scanning Electron Microscopes - Energy Dispersive Spectrometry (SEM-EDS) and Thermogravimetric Analysis (TGA). The addition of modified carbon black shows bound rubber, thermal properties, and mechanical properties such as tensile strength, elongation at break and modulus 300% on the vulcanisate produced were increased from the vulcanisate that had been filled with N660 natural (N660-N). Keywords: natural rubber, carbon black, particle size, sonofication, characterisation

scholarly journals Influence of Particle Size and Particle Range Distribution on the Microstructure of Al–Mg–Si/PKSA Composite for Amateur Solid Rocket Chamber

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Elijah O Oyedeji ◽  
Muhammed Dauda ◽  
Shehu A Yaro ◽  
Malik Abdulwahab
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Palm Kernel ◽  
Particle Size Analysis ◽  
Grain Structure ◽  
Size Analysis ◽  
Filler Materials ◽  
Powder Metallurgy Method ◽  
Unreinforced Alloy ◽  
Range Distribution

The study discusses an overview of small rocket program, development and characterization of locally sourced material at low cost. The aim is to enable the construction of small sounding rocket components for experimental purposes in Nigeria. This paper proposes the utilization of palm kernel shell ash as filler materials in the development, characterization and production of composite material to construct prototype reusable chamber and accessories that will enable it possible for small scientific experiments. To achieve this, particle size and particle range distribution on the microstructure, texture, and mechanical properties of (Al–Mg–Si)/PKSA composites developed by powder metallurgy method were investigated. The access in the 6xxx series of aluminum-magnesium-silicon alloy was investigated for this reason. ImageJ software was used to do particle size analysis professionally and the software was used to calculate the area, mean, standard deviation (SD) and the pixel values. The particle size distribution of big constituent (densification or rather densified solids) particles and small dispersoids possess a finer and slightly elongated grain structure when compared with the unreinforced alloy. The results of the XRD and XRF of all the samples considered showed that Al2O3, SiO2, Mn2O3 and MgO phases were common to all. These hard phases are considered to be responsible for improved mechanical properties and resistance of the composite, while the SEM result showed that the reinforcement was uniformly distributed which further improves the mechanical property of the composite.Keywords:  Microstructure, Composite, Rocket, Palm Kernel

scholarly journals SYNTHESIS OF NiO/ZnO NANOCOMPOSITES IN ETHYLENE GLYCOL

2020 ◽  
Author(s):  
Bakhtawar Sajjad ◽  
Umer Ali ◽  
Auswa Nadeem ◽  
Lubna Noor ◽  
Muhammad Akhyar Farrukh
Keyword(s):  
Differential Scanning Calorimetry ◽  
Particle Size ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Thermogravimetric Analysis ◽  
Ethylene Glycol ◽  
Sol Gel ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Scanning Calorimetry

Ethylene glycol is solvent used in sol-gel method to synthesize NiO/ZnO nanocomposites. ZnCl2 along with NiCl2.6H2O were used as precursors during synthetization of NiO/ZnO nanocomposites. We used various techniques such as Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and particle size analysis for synthesis of the nanocomposites which confirm that these nanocomposites act as catalyst.

Synthesis and Dispersion of PZT Ultra-Fine Powders

2006 ◽  
Vol 514-516 ◽  
pp. 179-183
Author(s):  
Ai Ying Wu ◽  
Dirk Van Genechten ◽  
Paula M. Vilarinho ◽  
Marlies K. Van Bael
Keyword(s):  
Aqueous Solution ◽  
Particle Size ◽  
Sol Gel ◽  
Aqueous Media ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Particle Charge ◽  
Powder Morphology ◽  
Fine Powders ◽  
Particle Size Analyzer

In the current work two different routes, an alkoxide based sol-gel and an aqueous solution-gel route, were used to synthesize PZT (30/70) powders. The phase purity, morphology and particle size of both were studied by XRD, TEM and particle size analysis. The dispersion behavior of the powders in water was investigated by means of light scattering particle size analyzer and zeta potential measurements. The extent to which powder morphology, synthesis route and particle charge state relate to the resulting dispersion behaviour was established. Alkoxide sol-gel derived powders are better dispersed in aqueous media than aqueous solution-gel derived powders.

scholarly journals Magnetite (Fe3O4) nanoparticles for chromium removal

2018 ◽  
Vol 53 (3) ◽  
pp. 219-224 ◽  
Author(s):  
MT Hossain ◽  
MM Hossain ◽  
MHA Begum ◽  
M Shahjahan ◽  
MM Islam ◽  
...  
Keyword(s):  
Particle Size ◽  
Fe3o4 Nanoparticles ◽  
Crystal Size ◽  
Sol Gel ◽  
Particle Size Analysis ◽  
Wave Number ◽  
Size Analysis ◽  
Ferric Nitrate ◽  
X Ray Diffraction ◽  
Magnetite Fe3o4

Magnetite (Fe3O4) nanoparticles were synthesized by sol-gel method using ferric nitrate and ethylene glycol as precursors at 250ºC and 300ºC. X-ray diffraction (XRD) study was used to determine the particle size and structural properties. The microstructural and particle size analysis were carried out using scanning electron microscope (SEM). Magnetite (Fe3O4) nanoparticles were annealed at 250ºC obtained as smaller crystal size than that of 300ºC. Fourier Transform Infrared (FTIR) spectroscopy was used to identify the functional groups of active compound in synthesized magnetite nanoparticles and their corresponding bands were observed in the region between 500cm-1 and 4000cm-1 of infrared radiation. The observed peaks at wave number 574cm-1 and 424cm-1 due to the vibration of tetrahedral and octahedral sites which is indicative the formation of spinel structure of magnetite (Fe3O4). Removal of Cr was found 80% by the synthesized magnetite (Fe3O4) nanoparticles 25g/L at pH 4.0 and contact time was 250 minutes. The results showed that prepared magnetite (Fe3O4) nanoparticles can be used for the treatment of wastewater containing chromium.Bangladesh J. Sci. Ind. Res.53(3), 219-224, 2018

Characterization of Simultaneously Gas Atomized Ti/TiC Composite Powders

2016 ◽  
Vol 704 ◽  
pp. 302-307 ◽  
Author(s):  
Tze Yang Yeh ◽  
Kuo Yuan Peng
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Powder Metallurgy ◽  
Metal Matrix ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Composite Powders ◽  
Tap Density ◽  
Mechanical Properties Testing

Metallic composite materials are mainly manufactured by powder metallurgy (PM) or casting, with reinforced ceramic particulates dispersed in a metal matrix. The current study presents an investigation with respect to simultaneously gas-atomized spherical Ti/TiC composite powders. Various analytical methods are used to characterize the gas-atomized Ti/TiC composite powders, including XRD, laser particle size analysis, flow rate tests, apparent density and tap density tests, SEM, and alike. The spherical Ti/TiC composite powders will be further laser sintered at the next stage to utilize mechanical properties testing.

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