ELECTRICAL PROPERTY OF CONVENTIONALLY SINTERED ZnO

2013 ◽  
Vol 22 ◽  
pp. 501-510 ◽  
Author(s):  
S. K. TAK ◽  
M. S. SHEKHWAT ◽  
R. MANGAL
Keyword(s):  
Sintering Temperature ◽  
Hold Time ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Phase Study ◽  
Average Grain Size ◽  
Structural And Electrical Properties ◽  
Different Temperatures ◽  
Zno Powder ◽  
Zno Ceramics

ZnO powder was synthesized by solid state reaction method. The synthesized powder was granulated and pressed using uni-axial press for preparing the pallets. The prepared pellets were sintered in conventional furnace at different temperatures (900-1300° C). The phase study was done by powder X-ray diffraction and it was found that the there is no other phase present in the synthesized material but the peak intensity is increasing with temperature. The crystallite size of the synthesized ZnO powder was found to be increase with temperature. The effect of sintering on grain growth is investigated by scanning electron microscopy (SEM). SEM revels that the average grain size is increases with increase in sintering temperature. AC impedance of these samples was decreased markedly with increased sintering temperature. In present work the effect of sintering temperatures and hold time on micro structural and electrical properties of ZnO ceramics is carried out.

scholarly journals Structural and electrical properties of strontium barium niobate thin films crystallized by conventional furnace and rapid-thermal annealing process

2001 ◽  
Vol 16 (10) ◽  
pp. 3009-3013 ◽  
Author(s):  
R. G. Mendes ◽  
E. B. Araújo ◽  
J. A. Eiras
Keyword(s):  
Thin Films ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
X Ray Diffraction ◽  
Strontium Barium Niobate ◽  
Strontium Barium ◽  
Conventional Furnace ◽  
Average Grain Size ◽  
Structural And Electrical Properties ◽  
Different Temperatures

Strontium barium niobate (SBN) thin films were crystallized by conventional electric furnace annealing and by rapid-thermal annealing (RTA) at different temperatures. The average grain size of films was 70 nm and thickness around 500 nm. Using x-ray diffraction, we identified the presence of polycrystalline SBN phase for films annealed from 500 to 700 °C in both cases. Phases such as SrNb2O6 and BaNb2O6 were predominantly crystallized in films annealed at 500 °C, disappearing at higher temperatures. Dielectric and ferroelectric parameters obtained from films crystallized by conventional furnace and RTA presented essentially the same values.

Figures of Merit of Low-Cost CuAl0.9Fe0.1O2 Thermoelectric Material Prepared at Different Solid State Reaction Sintering Temperatures

2015 ◽  
Vol 659 ◽  
pp. 185-189
Author(s):  
Aparporn Sakulkalavek ◽  
Rungnapa Thonglamul ◽  
Rachsak Sakdanuphab
Keyword(s):  
Figure Of Merit ◽  
Sintering Temperature ◽  
Low Cost ◽  
Uniaxial Pressure ◽  
Rhombohedral Structure ◽  
Second Phase ◽  
X Ray Diffraction ◽  
High Purity Grade ◽  
Average Grain Size ◽  
Xrd Patterns

In this study, we investigated a CuAl0.9Fe0.1O2 compound prepared at two different sintering temperatures in order to find out the effect of sintering temperature on the compound's figure of merit of thermoelectric properties. The thermoelectric CuAl0.9Fe0.1O2 compound was prepared from high purity grade Cu2O, Al2O3 and Fe2O3 powders. The mixture of these powders were ground and then pressed with uniaxial pressure into pellets. The pellets obtained were sintered in the air at 1423 K and 1473 K. X-ray diffraction (XRD) patterns showed a single phase of CuAl0.9Fe0.1O2 with rhombohedral structure, , along with a trace of CuO second phase. Moreover, the XRD peaks of the sample sintered at 1423 K indicated that more Fe3+ atoms replaced Al3+ atoms in this sample than they did in the sample sintered at 1473 K. The average grain size of the CuAl0.9Fe0.1O2 compound prepared increased with increasing sintering temperature, whereas its mean pore size and porosity decreased with increasing sintering temperature. The dispersed small pores markedly decreased the thermal conductivity of the compound, while the Fe3+ substitution of Al3+ increased its electrical conductivity. The highest figure of merit (ZT) found was 0.021 at 973 K in the CuAl0.9Fe0.1O2 sample sintered at 1423 K. Our findings show that this low-cost material with a reasonable figure of merit is a good candidate for thermoelectric applications at high-temperature.

Effect of Reinforcement and Tribological Behaviour of AA 7068 Hybrid Composites Manufactured through Powder Metallurgy Techniques

2017 ◽  
Vol 867 ◽  
pp. 19-28 ◽  
Author(s):  
J. Lakshmipathy ◽  
Subburaj Rajesh Kannan ◽  
K. Manisekar ◽  
S. Vinoth Kumar
Keyword(s):  
Sintering Temperature ◽  
Hybrid Composites ◽  
High Strength ◽  
Phase Changes ◽  
Wear Loss ◽  
X Ray Diffraction ◽  
Tribological Behaviour ◽  
Different Temperatures ◽  
Pin On Disc ◽  
Sliding Distance

In this article, an attempt was made to study the mechanical behaviour of AA7068 - 6 vol. % of MoS2 - X vol. % of WC (X = 0, 5, 10 and 15) hybrid aluminium composites produced by blend–press–sinter methodology. Compacted Powders (700MPa) were sintered at different temperatures (450 0c, 500 0c and 550 0c ) in order to find the influence of sintering temperature on mechanical properties and tribological behavior of AA7068 hybrid composites.The sintered samples have been characterized by x-ray diffraction (XRD) method for identification of phases and also to investigate the phase changes. The change in density, hardness and porosity values of composites were reported. The composite with 15 vol. % of tungsten carbide and 6 vol. % of MoS2 showed the highest hardness and density at the sintering temperature range of 550 0c. Pin-on-disc type apparatus was used for determining the wear loss occurring at different conditions. The hybridization of the two reinforcements enhanced the wear resistance of the composites, especially under high applied load, sliding distance and sliding speeds. Due to this, the hybrid aluminium composites can be considered as an outstanding material where high strength and wear-resistant components are of major importance, predominantly in the aerospace and automotive engineering sectors. The morphology of the wear debris and the worn out surfaces were analyzed to understand the wear mechanisms.

CHARACTERIZATION OF HYDROXYAPATITE/TI6AL4V COMPOSITE POWDER UNDER VARIOUS SINTERING TEMPERATURE

2015 ◽  
Vol 75 (7) ◽  
Author(s):  
Amir Arifin ◽  
Abu Bakar Sulong ◽  
Norhamidi Muhamad ◽  
Junaidi Syarif
Keyword(s):  
Mechanical Properties ◽  
Composite Powder ◽  
Sintering Temperature ◽  
Physical And Mechanical Properties ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Different Temperatures ◽  
Two Phases ◽  
Work Interaction

Hydroxyapatite (HA) has been widely used in biomedical applications due to its excellent biocompatibility. However, Hydroxyapatite possesses poor mechanical properties and only tolerate limited loads for implants. Titanium is well-known materials applied in implant that has advantage in mechanical properties but poor in biocompatibility. The combination of the Titanium alloy and HA is expected to produce bio-implants with good in term of mechanical properties and biocompatabilty. In this work, interaction and mechanical properties of HA/Ti6Al4V was analyzed. The physical and mechanical properties of HA/Ti6Al4V composite powder obtained from compaction (powder metallurgy) of 60 wt.% Ti6Al4V and 40 wt.% HA and sintering at different temperatures in air were investigated in this study. Interactions of the mixed powders were investigated using X-ray diffraction. The hardness and density of the HA/Ti6Al4V composites were also measured. Based on the results of XRD analysis, the oxidation of Ti began at 700 °C. At 1000 °C, two phases were formed (i.e., TiO2 and CaTiO3). The results showed that the hardness HA/Ti6Al4V composites increased by 221.6% with increasing sintering temperature from 700oC to 1000oC. In contrast, the density of the composites decreased by 1.9% with increasing sintering temperature. 

scholarly journals Pengaruh Suhu Sintering Terhadap Sintesis Silicon Carbide (SiC) Berbahan Dasar Abu Sekam Padi dan Grafit Pensil 2B

2015 ◽  
Vol 5 (01) ◽  
pp. 31
Author(s):  
Resky Irfanita ◽  
Asnaeni Ansar ◽  
Ayu Hardianti Pratiwi ◽  
Jasruddin J ◽  
Subaer S
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Silicon Carbide ◽  
Rice Husk Ash ◽  
Sintering Temperature ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Reaction Method ◽  
X Ray ◽  
Scanning Electron

The objective of this study is to investigate the effect of sintering temperature on the synthesis of SiC produced from rice husk ash (RHA) and 2B graphite pencils. The SiC was synthesized by using solid state reaction method sintered at temperatures of 750°C, 1000°C and 1200°C for 26 hours, 11.5 hours and 11.5 hours, respectively. The quantity and crystallinity level of SiC phase were measured by means of Rigaku MiniFlexII X-Ray Diffraction (XRD). The microstructure of SiC was examined by using Tescan Vega3SB Scanning Electron Microscopy (SEM). The XRD results showed that the concentration (wt%) of SiC phase increases with the increasing of sintering temperature. SEM results showed that the crystallinity level of SiC crystal is improving as the sintering temperature increases

Effect of Sintering Temperature on Microstructure and Electrical Properties of Nanozinc Oxide Varistor

2011 ◽  
Vol 495 ◽  
pp. 190-193 ◽  
Author(s):  
Mehdi Mirzayi ◽  
Mohammad Hoseen Hekmatshoar ◽  
Abdolazim Azimi
Keyword(s):  
Electrical Properties ◽  
Sintering Temperature ◽  
Voltage Characteristic ◽  
X Ray Diffraction ◽  
Current Voltage Characteristic ◽  
X Ray ◽  
Current Voltage ◽  
Polyacrylamide Gel Method ◽  
Zno Powder ◽  
Scanning Electron

Nanometer-sized ZnO powder was synthesized at low decomposing temperature by polyacrylamide-gel method where Acrylamide was used as monomer, and N,N-methylene-bisacrylamide as lattice reagent. The characteristic of powders were studied by X-ray diffraction and scanning electron microscope (SEM). The results indicated uniform distribution of nanoZnO particles. Also electrical properties were investigated at different sintering temperatures of 800, 900 and 1000 ° C. It was observed that increase in sintering temperature, resulted in increase in the grain size of the varistor ceramics. The observed nonlinearity in current – voltage characteristic was explained by the existence of potential barrier at the grain boundaries and lowering of the barriers.

The Structure-Property-Processing Relationship for Sintered Yttria-Stabilized Zirconia (YSZ)/Alumina Bioceramics

2013 ◽  
Vol 25 (04) ◽  
pp. 1350005 ◽  
Author(s):  
Sea-Fue Wang ◽  
Thomas Chung-Kuang Yang ◽  
Ya-Ting Hsu ◽  
Sheng-Yang Lee ◽  
Jen-Chang Yang
Keyword(s):  
Fracture Toughness ◽  
Relative Density ◽  
Sintering Temperature ◽  
High Hardness ◽  
Solid State Reaction Method ◽  
Sintering Behavior ◽  
Structure Property ◽  
Stabilized Zirconia ◽  
Average Grain Size ◽  
Alumina Addition

The objective of this research is to study the effects of alumina addition on the microstructure-mechanical property relationship and sintering behavior of yttria (3 mol%)-stabilized zirconia (YSZ) ceramics. Well-dispersed YSZ / Al 2 O 3 ceramics containing 10–40 wt.% Al 2 O 3 were prepared by solid state reaction method. The relative density, average grain size, lattice parameters, microhardness, and fracture toughness of YSZ / Al 2 O 3 ceramics system sintered in the temperature range of 1250~1500°C as a function of Al 2 O 3 content were investigated. Experimental results showed that the ceramics with high Al 2 O 3 content and low sintering temperature tended to reveal low bulk densities. But the Al 2 O 3 content dependence on relative density for YSZ / Al 2 O 3 ceramics becomed deminishing when increasing the sintering temperature. Dense ceramics with composition of (80/20) ( YSZ / Al 2 O 3) and sintered at temperature of 1400°C and 1450°C revealed the optimal Vickers hardness and fracture toughness properties. These ceramics with high Al 2 O 3 content tended to reveal small grain sizes. The high sintering temperature governs the slow grain growth and high hardness in materials indicating the good correlation between microstructure of fabricated dense and mechanical properties.

Low Temperature Aqueous Polymeric Precursor Processing of ZnO:Er Using a Glycerol Chelating Agent

2006 ◽  
Vol 957 ◽  
Author(s):  
Uma Choppali ◽  
Brian P Gorman
Keyword(s):  
Thin Films ◽  
Low Temperature ◽  
Doping Concentration ◽  
Compressive Strain ◽  
Chelating Agent ◽  
X Ray Diffraction ◽  
Er Doping ◽  
Structural And Electrical Properties ◽  
Different Temperatures ◽  
Surface Modified

ABSTRACTErbium doped ZnO (ZnO:Er) is considered to be a suitable candidate for fabrication of the current injection optical devices. Although ZnO: Er thin films have been synthesized previously by pulsed laser deposition, we present low – temperature processed ZnO:Er thin films from polymeric precursors. In this work, we study the effect of variation of Er doping concentration on the structural and electrical properties of the synthesized films. ZnO nanoparticles of varied Er doping concentration, derived from the prepared polymeric solution, has been spin – coated onto surface modified substrates, and annealed at different temperatures. The effect of Er doping concentration on film grain size and strain was analyzed using X-ray diffraction. XRD data reveals that doping of Er ions reduces compressive strain considerably in the films. It is speculated that the presence of larger Er cations in ZnO cause tensile stress, which neutralizes the inherent compressive stress, observed in undoped ZnO, significantly decreasing and hence, making the films stress free. Crystallite size of ZnO:Er thin films, annealed at 600°C, was calculated to be approximately 12 nm using Scherrer's equation. The surface morphology of the thin films was characterized by both SEM and AFM. Electrical resistivity of the films, annealed at 450oC, was calculated to be 290 Ω-m for 5 at wt% and 125 Ω-m for 10 at wt% ZnO:Er films.

Structural, Morphological and Composition Analysis of Nanocrystalline La0.67Ba0.33MnO3 Powder

2012 ◽  
Vol 584 ◽  
pp. 239-242
Author(s):  
C. Seshendra Reddy ◽  
A. Sivasankar Reddy ◽  
P. Sreedhara Reddy
Keyword(s):  
Grain Size ◽  
Sintering Temperature ◽  
Base Material ◽  
Solid State Reaction Method ◽  
Rhombohedral Structure ◽  
Composition Analysis ◽  
Scanning Electron Micrographs ◽  
Atomic Force ◽  
Average Grain Size ◽  
Composition Properties

La0.67Ba0.33MnO3 powders were successfully prepared by a standard solid state reaction method, and systematically investigated the influence of the sintering temperature on the structural, microstructure, composition properties. The XRD pattern showed that the as prepared LBMO material was in single-phase with rhombohedral structure. From the scanning electron micrographs, it was observed that the grain size increased with sintering temperature and the average grain size was ~40nm.The surface roughness was measured by atomic force microscope and the RMS roughness of samples was in the range 48 to 85 nm. The as prepared samples exhibited nearly the same composition of the base material.

Luminescence Behavior of Tm3+ Activated GdAlO3 Phosphors Synthesized Using Solid-Reaction Method

2014 ◽  
Vol 602-603 ◽  
pp. 32-37 ◽  
Author(s):  
Nan Wu ◽  
Xiao Dong Li ◽  
Shao Hong Liu ◽  
Yu Dong ◽  
Ji Guang Li ◽  
...  
Keyword(s):  
Decay Curve ◽  
Exchange Interactions ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Nanosized Powders ◽  
Reaction Method ◽  
X Ray ◽  
Pure Phase ◽  
Different Temperatures ◽  
High Color Purity

Trivalent thulium ions (Tm3+) doped GdAlO3 (Gd1-xTmxAlO3) phosphors which show a blue luminescence of high color purity have been synthesized by using solid-state reaction method starting from nanosized powders. X-ray diffraction (XRD) measurements were used to analyze the phase transformations that take place during the preparation of the phosphors. The morphologies of the powders calcined at different temperatures were studied by using scanning electron microscopy (SEM). The luminescence properties of the compounds were investigated. Pure phase of orthorhombic type GdAlO3 (GAP) was yielded by calcining the phosphors at 1200°C for 8 h. The PL spectra showed representative Tm3+ emission. The strong band centered at ~488 nm and the weak one centered at 697 nm were attributed to the 1D2-3F4 and 1G4-3F4 transitions of Tm3+, respectively. The quenching concentration of Tm3+ was estimated to be ~0.75at.% (x=0.0075), for which can be ascribed to the exchange interactions. The decay curve was fitted to be a single exponent and the estimated fluorescent lifetime of the GdAlO3:Tm3+ phosphor was 1.73±0.08 ms.

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