scholarly journals A Study of Cordierite Ceramics Synthesis From domestic kaolin

2021 ◽  
Vol 947 (1) ◽  
pp. 012021
Author(s):  
Kim Tuan ◽  
Dinh Huu Phong ◽  
Minh Tam Lam ◽  
Viet Thai Nguyen ◽  
Minh-Vien Le ◽  
...  
Keyword(s):  
Formation Rate ◽  
Stoichiometric Composition ◽  
X Ray Diffraction ◽  
Solid State Reaction Technique ◽  
Aluminum Nitrate Nonahydrate ◽  
Chloride Hexahydrate ◽  
Lower Temperature ◽  
Cordierite Ceramics ◽  
Chlorine Ion ◽  
Effect Of Chlorine

Abstract This work aims to study the effect of chlorine ion on the formation of the cordierite phase (2MgO.2Al2O3.5SiO2) from domestic kaolin at various calcined temperatures.. The cordierite phase was synthesized by a solid-state reaction technique from the mixture of kaolin, aluminum nitrate nonahydrate (Al(NO3)3.9H2O), and magnesium chloride hexahydrate (MgCl2.6H2O) which was designed to the stoichiometric composition of cordierite in the absence and presence of chlorine ion (NH4Cl). The structure and formation of cordierite phase were characterized by X-ray diffraction (XRD) and thermogravimetric - differential thermal analysis (TG-DSC). Phase composition of samples calcined at various temperatures was calculated by using Match! (Version 3.7.0) software. It is noteworthy that the presence of chlorine ion in the mixture declined the formation temperature of cordierite by 50 °C. The cordierite phase was calculated to be 61.3 wt.% and 5.5 wt.% at 1150 °C for the present and absent chlorine ion, respectively. The presence of chlorine ion affected the cordierite formation rate and suppressed the temperature of formation. Cordierite phase could be obtained up to 89.6 wt.% at 1250 °C and 30 wt.% NH4Cl. This investigation found that cordierite ceramic could be synthesized from domestic kaolin at lower temperature by using NH4Cl additive.

scholarly journals Sintering of cordierite in the presence of MoO3 and crystallization analysis

2014 ◽  
Vol 46 (3) ◽  
pp. 307-313 ◽  
Author(s):  
N. Djordjevic ◽  
N. Obradovic ◽  
D. Kosanovic ◽  
M. Mitric ◽  
V.P. Pavlovic
Keyword(s):  
Binary Systems ◽  
Sintering Temperature ◽  
Preparation Process ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sintering Time ◽  
Lower Temperature ◽  
Cordierite Ceramics ◽  
Low Temperature Process

Cordierite (MAS) is difficult to sinter because of the very narrow sintering temperature range (1300-1400?C). Because a low temperature process is desirable, it is necessary to find functional ads which can allow easier sintering process at lower temperature. The influence of MoO3 on the preparation process of cordierite ceramics was investigated. 2MgO-2Al2O3-5SiO2 was researched by sintering followed binary systems: MgO/MoO3, Al2O3/MoO3 and SiO2/MoO3 (all sintered at 850?C and 1100?C, sintering time 2h). Composition of these systems was 80 mass% of oxide and 20 mass% MoO3. The effects of sintering, the composition and morphology were followed by X-ray diffraction and SEM microscopy. It has been found that MoO3, beside liquid phase, forms intermediary unstable compounds with MgO and Al2O3, which is the significance information for further research. MAS ceramics were sintered with 20 mass% MoO3 at 1100?C, 1200?C and 1300?C, during 2h.

TEM studies of solid-state reactions in sputter-deposited Nb/Al multilayer thin films

1996 ◽  
Vol 54 ◽  
pp. 1020-1021
Author(s):  
F. Ma ◽  
S. Vivekanand ◽  
K. Barmak ◽  
C. Michaelsen
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Stoichiometric Composition ◽  
Analytical Electron Microscopy ◽  
Grain Structure ◽  
Solid State Reactions ◽  
Multilayer Thin Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sputter Deposited

Solid state reactions in sputter-deposited Nb/Al multilayer thin films have been studied by transmission and analytical electron microscopy (TEM/AEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The Nb/Al multilayer thin films for TEM studies were sputter-deposited on (1102)sapphire substrates. The periodicity of the films is in the range 10-500 nm. The overall composition of the films are 1/3, 2/1, and 3/1 Nb/Al, corresponding to the stoichiometric composition of the three intermetallic phases in this system.Figure 1 is a TEM micrograph of an as-deposited film with periodicity A = dA1 + dNb = 72 nm, where d's are layer thicknesses. The polycrystalline nature of the Al and Nb layers with their columnar grain structure is evident in the figure. Both Nb and Al layers exhibit crystallographic texture, with the electron diffraction pattern for this film showing stronger diffraction spots in the direction normal to the multilayer. The X-ray diffraction patterns of all films are dominated by the Al(l 11) and Nb(l 10) peaks and show a merging of these two peaks with decreasing periodicity.

Studies about Electrochemical Plating with Zinc - nickel Alloys - the Influence of Deposition Potential on Stoichiometric Composition

2008 ◽  
Vol 59 (9) ◽  
Author(s):  
Violeta Vasilache ◽  
Gheorghe Gutt ◽  
Traian Vasilache
Keyword(s):  
Nickel Alloys ◽  
Stoichiometric Composition ◽  
Nickel Chloride ◽  
Deposition Potential ◽  
X Ray Diffraction ◽  
Pure Zinc ◽  
X Ray ◽  
Nickel Cobalt ◽  
Cobalt Iron ◽  
Electrochemical Plating

The electrochemical deposition of zinc and combinations with elements of the 8th group of the Periodic System (nickel, cobalt, iron) have good properties for anticorrosive protection, compared with pure zinc. For steel pieces, these films delay apparition and formation of white and red iron oxide. We used solutions with different concentrations of zinc chloride, nickel chloride and potassium chloride. To analyze the results we used the optic microscope and the X-ray diffraction.

scholarly journals An accelerated and effective synthesis of zinc borate from zinc sulfate using sonochemistry

2020 ◽  
Vol 43 (1) ◽  
pp. 7-14
Author(s):  
Ali Can Ersan ◽  
Azmi Seyhun Kipcak ◽  
Meral Yildirim Ozen ◽  
Nurcan Tugrul
Keyword(s):  
Inorganic Compounds ◽  
Zinc Borate ◽  
High Yield ◽  
X Ray Diffraction ◽  
Ultrasonic Probe ◽  
Minimum Particle Size ◽  
Effective Synthesis ◽  
Ft Ir ◽  
Lower Temperature ◽  
Borate Compound

AbstractRecently, sonochemistry has been used for the synthesis of inorganic compounds, such as zinc borates. In this study using zinc sulphate heptahydrate (ZnSO4·7H2O) and boric acid (H3BO3) as starting materials, a zinc borate compound in the form of Zn3B6O12·3.5H2O was synthesized using an ultrasonic probe. Product’s characterization was carried out with using X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and Raman spectroscopy. Zinc borate compound’s chemical bond structure was observed with Raman and FTIR. From the XRD results it was seen that Zn3B6O12·3.5H2O can be quickly synthesized upon heating at 80°C and 85°C (55 min) or 90°C (45 min) in very high yield (>90%). The minimum particle size obtained was ~143 μm from the SEM results. Zinc borate compound was synthesized at a lower temperature in less time than other synthesized zinc metal compound in literature.

scholarly journals Transport and Dielectric Properties of Mechanosynthesized La2/3Cu3Ti4O12 Ceramics

Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 313
Author(s):  
Mohamad M. Ahmad ◽  
Hicham Mahfoz Kotb ◽  
Celin Joseph ◽  
Shalendra Kumar ◽  
Adil Alshoaibi
Keyword(s):  
Dielectric Constant ◽  
Sintering Temperature ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
Boundary Conductivity ◽  
X Ray ◽  
Giant Dielectric ◽  
Mechanochemical Milling ◽  
Giant Dielectric Constant ◽  
Lower Temperature

La2/3Cu3Ti4O12 (LCTO) powder has been synthesized by the mechanochemical milling technique. The pelletized powder was conventionally sintered for 10 h at a temperature range of 975–1025 °C, which is a lower temperature process compared to the standard solid-state reaction. X-ray diffraction analysis revealed a cubic phase for the current LCTO ceramics. The grain size of the sintered ceramics was found to increase from 1.5 ± 0.5 to 2.3 ± 0.5 μm with an increase in sintering temperature from 975 to 1025 °C. The impedance results show that the grain conductivity is more than three orders of magnitude larger than the grain boundary conductivity for LCTO ceramics. All the samples showed a giant dielectric constant (1.7 × 103–3.4 × 103) and dielectric loss (0.09–0.17) at 300 K and 10 kHz. The giant dielectric constant of the current samples was attributed to the effect of internal barrier layer capacitances due to their electrically inhomogeneous structure.

Effect of the BSCCO superconducting properties by tiny Y2O3 addition

2016 ◽  
Vol 30 (26) ◽  
pp. 1650328
Author(s):  
Yan Dong ◽  
Aimin Sun ◽  
Bin Xu ◽  
Hongtao Zhang ◽  
Meng Zhang
Keyword(s):  
Volume Fraction ◽  
Superconducting Properties ◽  
X Ray Diffraction ◽  
Critical Transition Temperature ◽  
Solid State Reaction Technique ◽  
X Ray ◽  
Oxide Addition ◽  
One Step ◽  
Step Transition ◽  
Y2o3 Addition

In this paper, the effect of tiny Y2O3 addition in (Bi,[Formula: see text]Pb)-2223 superconductor prepared by solid state reaction technique was studied. The properties of samples have been investigated via X-ray diffraction (XRD), resistance–temperature ([Formula: see text]–[Formula: see text]) curve, scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). XRD data indicated that all samples are multiphase and the major phases are high-temperature phases and low-temperature phases. The volume fraction of (Bi,[Formula: see text]Pb)-2223 is not great change with tiny Y2O3 addition. All samples exhibit superconducting phase with the critical transition temperature and one-step transition, however, the transition width was decreased with the Y2O3 addition up to 0.04 wt.% and sharp increased with the excessive oxide addition. SEM pictures show that the Y2O3 appeared on the flake-type grains surface obviously, but the number and size of the hole between grains are decreased in the 0.04 wt.% addition.

Effect of Sintering Temperature on Electrical Properties of SFN Ceramics Doped with Al Prepared by a Solid-State Reaction Technique

2016 ◽  
Vol 675-676 ◽  
pp. 527-530
Author(s):  
Thanatep Phatungthane ◽  
Kachaporn Sanjoom ◽  
Denis Russell Sweatman ◽  
Buagun Samran ◽  
Chamnan Randorn ◽  
...  
Keyword(s):  
Solid State ◽  
Electrical Properties ◽  
Solid State Reaction ◽  
Sintering Temperature ◽  
Perovskite Phase ◽  
Dielectric Behavior ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Solid State Reaction Technique ◽  
Pure Perovskite Phase

In the present work, strontium iron niobate SrFe0.5Nb0.5O3 ceramics doped with aluminum were synthesized by a solid-state reaction technique. Phase formation investigation by X-ray diffraction technique (XRD) revealed that all ceramics exhibited pure perovskite phase with orthorhombic symmetry. Grain size observed by electron microscopy (SEM) was found to increase with increasing sintering temperature. The electrical properties and related parameters of the ceramics were also measured. The ceramics exhibit very good dielectric behavior and have a significant potential for dielectric applications.

Modulated vacancy ordering in SrGe6−x (x≈0.45)

2019 ◽  
Vol 74 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Ulrich Schwarz ◽  
Rodrigo Castillo ◽  
Aron Wosylus ◽  
Lev Akselrud ◽  
Yurii Prots ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Ambient Pressure ◽  
Stoichiometric Composition ◽  
Binary Compound ◽  
Crystal Structure Analysis ◽  
Local Defect ◽  
X Ray Diffraction ◽  
Vacancy Ordering ◽  
Metal Type ◽  
A Charge

AbstractThe structural properties of modulated SrGe6−x (x≈0.45) were investigated by means of single-crystal and powder X-ray diffraction combined with quantum chemical calculations. The framework compound SrGe6−x adopts a defect variant of the EuGa2Ge4-type crystal structure. Samples of the binary compound with nominal compositions 0≤x≤0.5 were synthesized at pressures from 5 to 6 GPa and a temperature of typically 1400 K. The product reveals diffraction peaks of the EuGa2Ge4-type subcell plus additional reflections indicating an ordered superstructure. Detailed crystal structure analysis evidences the incommensurate nature of the superstructure and a modulation of the vacancy ordering in the germanium network. The computations have shown that the non-stoichiometric composition of the framework with its local defect organization affects the calculated charge of the strontium anions. Although the chemical composition is close to a charge-balanced situation, temperature-dependent resistivity measurements showed metal-type conductivity. At ambient pressure SrGe6−x decomposes exothermally and irreversibly at T=680(10) K into SrGe2 and germanium, indicating its metastable nature at ambient pressure.

Reaction Synthesis and Oxidation Behaviours of Ludwigite

2010 ◽  
Vol 146-147 ◽  
pp. 475-480 ◽  
Author(s):  
Ran Liu ◽  
Xing Juan Wang ◽  
Yong Liang Gao ◽  
Qing Lu ◽  
Xiang Xin Xue
Keyword(s):  
Weight Loss ◽  
Mass Loss Rate ◽  
Mass Gain ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Blast Furnace Smelting ◽  
Isothermal Tg ◽  
Lower Temperature ◽  
Xrd Techniques ◽  
Furnace Smelting

Using ludwigite as raw material, the phase transformation and mass loss rate of ludwigite in the process of oxidizing roasting are investigated by DTA, isothermal TG, scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques. The results showed that magnetite is transformed into hematite, serpentine is decomposed into forsterite at lower temperature (T＜700°C). The weight of ludwigite has a small loss below 600°C. The decomposed of szaibelyite dehydrated and formed into suanite about 700°Cis the main reason of causing ludwigite mass losses. By comparing the curves of ludwigite at different temperature from 700 to 900°C, the process of oxidizing roasting can be divided into three phases: characterized by a period of fast weight loss, and then followed by a mass gain. Finally, weight of sample is no longer change with prolongation of time. The final weight loss is 6.062%, 6.658% and 7.442% respectively for test temperature. Suanite can not be decomposed to form B2O3 and volatilized when the temperature of oxidizing roasting is below 1142 °C. It is found by XRD that paigeite and magnoferrite are the most stable composition without deterioration on oxidizing roasting. The experiment results can provide theoretical references for agglomeration and blast furnace smelting of ludwigite.

scholarly journals Study of Microstructural, Electrical and Dielectric Properties of La0.9Pb0.1MnO3 and La0.8Y0.1Pb0.1MnO3 Ceramics

2019 ◽  
pp. 33-44 ◽  
Keyword(s):  
Transition Temperature ◽  
Frequency Dispersion ◽  
Insulator Transition ◽  
X Ray Diffraction ◽  
Phonon Modes ◽  
Metal Insulator Transition ◽  
Metal Insulator ◽  
Solid State Route ◽  
Distorted Structure ◽  
Lower Temperature

The present work studies the microstructural and electrical properties of La0.9Pb0.1MnO3 and La0.8Y0.1Pb0.1MnO3 ceramics synthesized by solid-state route method. Microstructure and elemental analysis of both samples were carried out by field emission scanning electron microscope (FESEM) and energy dispersive spectroscopy (EDS) method, respectively. Phase analysis by X-ray diffraction (XRD) indicated formation of single phase distorted structure. The XRD data were further analyzed by Rietveld refinement technique. Raman analysis reveals that Y atom substitutes La site into the LPMO with shifting of phonon modes. The temperature variation of resistivity of undoped and Y-doped La0.9Pb0.1MnO3 samples have been investigated. The electrical resistivity as a function of temperature showed that all samples undergo an metal-insulator (M-I) transition having a peak at transition temperature TMI. Y-doping increases the resistivity and the metal-insulator transition temperature (TMI) shifts to lower temperature. The temperature-dependent resistivity for temperatures less than metal-insulator transition is explained in terms the quadratic temperature dependence and for T > TMI, thermally activated conduction (TAC) is appropriate. Variation of frequency dispersion in permittivity and loss pattern due to La-site substitution in LPMO was observed in the dielectric response curve.

Sign in / Sign up

Export Citation Format

Share Document