scholarly journals Dielectric and Electric Properties of Ba0.996La0.004Ti0.999O3 Ceramics Doped with Europium and Hafnium Ions

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 413
Author(s):  
Małgorzata Adamczyk-Habrajska ◽  
Beata Wodecka-Duś ◽  
Tomasz Goryczka ◽  
Diana Szalbot ◽  
Mateusz Bara ◽  
...  
Keyword(s):  
Grain Size ◽  
Electron Microscope ◽  
Impedance Spectroscopy ◽  
Piezoelectric Properties ◽  
Ceramic Materials ◽  
Strong Correlations ◽  
Electric Permittivity ◽  
Dielectric Characteristics ◽  
Dielectric And Piezoelectric Properties ◽  
Scanning Electron

Lanthanum-modified BaTiO3 electroceramic materials have superior dielectric and piezoelectric properties. Ba0.996La0.004Ti0.999O3 (BLT4) seems to be a serious candidate for ultracondensator applications. This manuscript describes the results of hafnium and europium modification of BLT 4 ceramics. The pure and doped ceramic materials were synthesized by the conventional mixed oxide method. The microstructure of obtained samples was examined by scanning electron microscope. The investigations reveal strong correlations between the presence of admixture and the grain size, which was especially visible in the case of the hafnium dopant. The frequency and temperature dielectric characteristics measurements revealed a decrease in electric permittivity. Moreover, the impedance spectroscopy investigations showed severe changes in grains and grain-boundary resistivity, which was connected with changes in electric conductivity.

Sintering Process of Nd:YAG Transparent Ceramic

2013 ◽  
Vol 281 ◽  
pp. 475-479
Author(s):  
Bo Wang ◽  
Quan Xi Cao ◽  
Guang Xu ◽  
Sen Tian
Keyword(s):  
Grain Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Crystal Structures ◽  
Heating Rate ◽  
Optical Transmittance ◽  
Sintering Process ◽  
X Ray ◽  
Polycrystalline Ceramics ◽  
Scanning Electron

1.0at% Nd:YAG polycrystalline ceramics were sintered at 1420°C, 1500°C, 1600°C and 1730°C respectively by different heating rate (1°C/min and 5°C/min). The crystal structures were indexed by X-ray diffractometer (XRD). The microstructure and the grain size of the samples were characterized by scanning electron microscope (SEM). The optical transmittance spectra of the samples were measured using V-570 UV spectrophotometer. The sintering process of Nd:YAG ceramics and the effect of heating rate on the microstructure of samples have been investigated.

Study on the Properties of Doped La in BaBi4Ti4O15 Ceramic

2007 ◽  
Vol 26-28 ◽  
pp. 243-246
Author(s):  
Xing Hua Yang ◽  
Jin Liang Huang ◽  
Xiao Wang ◽  
Chun Wei Cui
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sintering Temperature ◽  
Solid Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lanthanum Content ◽  
Scanning Electron

BaBi4-xLaxTi4O15 (BBLT) ceramics were prepared by conventional solid phase sintering ceramics processing technology. The crystal structure and the microstructure were detected by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD analyses show that La3+ ions doping did not change the crystal structure of BBT ceramics. The sintering temperature increased from 1120°C to 1150°C with increasing Lanthanum content from 0 to 0.5, but it widened the sintering temperature range from 20°C to 50°C and refined the grain size of the BBT ceramic. Additionally, polarization treatment was performed and finally piezoelectric property was measured. As a result, the piezoelectric constant d33 of the 0.1at.% doped BBLT ceramics reached its highest value about 22pc/N at polarizing electric field of 8kV/mm and polarizing temperature of 120°C for 30min.

scholarly journals Spatial Resolutions of On-Axis and Off-Axis Transmission Kikuchi Diffraction Methods

2019 ◽  
Vol 9 (21) ◽  
pp. 4478 ◽  
Author(s):  
Yitian Shen ◽  
Jingchao Xu ◽  
Yongsheng Zhang ◽  
Yongzhe Wang ◽  
Jimei Zhang ◽  
...  
Keyword(s):  
Grain Size ◽  
Electron Microscope ◽  
Spatial Resolution ◽  
Correlation Coefficients ◽  
Sample Thickness ◽  
Phase Identification ◽  
Specimen Thickness ◽  
Key Factors ◽  
Orientation Microscopy ◽  
Scanning Electron

Spatial resolution is one of the key factors in orientation microscopy, as it determines the accuracy of grain size investigation and phase identification. We determined the spatial resolutions of on-axis and off-axis transmission Kikuchi diffraction (TKD) methods by calculating correlation coefficients using only the effective parts of on-axis and off-axis transmission Kikuchi patterns. During the calculation, we used average filtering to evaluate the spatial resolution more accurately. The spatial resolutions of both on-axis and off-axis TKD methods were determined in the same scanning electron microscope at different accelerating voltages and specimen thicknesses. The spatial resolution of the on-axis TKD was higher than that of the off-axis TKD at the same parameters. Furthermore, with an increase in accelerating voltage or a decrease in specimen thickness, the spatial resolutions of the two configurations could be significantly improved, from tens of nanometers to below 10 nm. At a voltage of 30 kV and sample thickness of 74 nm, both on-axis and off-axis TKD methods exhibited the highest resolutions of 6.2 and 9.7 nm, respectively.

Grain Size Effect on Dielectric and Piezoelectric Properties of Alkoxy-Derived BaTiO3-Based Thin Films

2004 ◽  
Vol 43 (9B) ◽  
pp. 6525-6529 ◽  
Author(s):  
Kiyotaka Tanaka ◽  
Kazuyuki Suzuki ◽  
Desheng Fu ◽  
Kaori Nishizawa ◽  
Takeshi Miki ◽  
...  
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Size Effect ◽  
Piezoelectric Properties ◽  
Grain Size Effect ◽  
Dielectric And Piezoelectric Properties

Influence of the powder grain size on dielectric and piezoelectric properties of lead-free KxNa1-xNbO3 piezoelectric ceramics

2019 ◽  
Vol 539 (1) ◽  
pp. 89-92
Author(s):  
S. Grigorevich Ponomarev ◽  
V. Pavlovich Tarasovskii ◽  
A. Vladimirovich Reznichenko ◽  
A. Aleksandrovich Vasin
Keyword(s):  
Grain Size ◽  
Piezoelectric Properties ◽  
Piezoelectric Ceramics ◽  
Lead Free ◽  
Dielectric And Piezoelectric Properties

In Situ Scanning Electron Microscopy Observation of the Pattern Formation on the Surface of Al/Ge Bilayer Films

2007 ◽  
Vol 539-543 ◽  
pp. 3568-3573
Author(s):  
H. Kumagai ◽  
M. Shibata ◽  
Tomokazu Moritani ◽  
Takao Kozakai ◽  
Minoru Doi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Free Surface ◽  
Electron Microscope ◽  
Microscopy Observation ◽  
Bilayer Films ◽  
Fractal Patterns ◽  
Scanning Electron

When the Al/Ge/SiO2 bilayer films are annealed in-situ in a scanning electron microscope (SEM) at the temperatures lower than the crystallization temperature of amorphous Ge itself, the so-called metal-mediated-crystallization (MMC) takes place. In the course of MMC, crystalline Ge aggregates (Ge clusters) form in the bilayer films, which results in the formation and the evolution of impressive fractal patterns with branching on the free surface. In-situ SEM observations of annealed Al/Ge/SiO2 bilayer films indicate that the grain size of polycrystalline Al-layer influences the nucleation of Ge clusters and hence of fractal patterns. For the bilayer films containing larger Al grains, the nucleation rate of fractal patterns (Ge clusters) is faster and the number of patterns is larger.

Epoxy Resin Modified with PEDOT/PSS and Corrosion Protection of Steel

2012 ◽  
Vol 560-561 ◽  
pp. 947-951
Author(s):  
Jian Hou ◽  
Guang Zhu ◽  
Jing Kun Xu ◽  
Jun Tao Wang ◽  
Yao Huang
Keyword(s):  
Electron Microscope ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Scanning Electron Microscope ◽  
Epoxy Resin ◽  
Corrosion Protection ◽  
Electrochemical Impedance ◽  
Protection Efficiency ◽  
Epoxy Paint ◽  
Scanning Electron

An epoxy paint containing PEDOT/PSS was described herein. The corrosion behavior of steel samples coated with the paint was investigated in seawater. For this purpose, electrochemical impedance spectroscopy was utilized and surface morphology of coatings after corrosion was observed using scanning electron microscope. It was found that the addition of small PEDOT/PSS to the epoxy resin increased its corrosion protection efficiency. Meanwhile, the possible mechanism was discussed.

scholarly journals Mineral Preparation Using Rod Mill for Mineral Galena Characterization

2021 ◽  
Vol 1 (1) ◽  
pp. 355-362
Author(s):  
Riria Zendy Mirahati ◽  
Yasmina Amalia ◽  
Mochamad Juliyanto ◽  
Lintang Larasati Adi Putri
Keyword(s):  
Grain Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Grinding Process ◽  
X Ray Diffraction ◽  
Mineral Concentration ◽  
X Ray ◽  
Concentration Process ◽  
Mineral Characterization ◽  
Scanning Electron

Galena mineral preparation was carried out for mineral characterization. The mineral characterization carried out included XRD (X-Ray Diffraction), XRF (X-Ray Fluorescence), SEM-EDS (Scanning Electron Microscope-Energy Dispersive X-Ray). The preparation of galena minerals begins with the process of reducing the grain size including crushing and grinding. The results of crushing and grinding are then separated based on grain size using a sieve or siever to get a grain size of -200 mesh. The grinding process using a rod mill needs to be timed, so that the results are not too fine which is causing the recovery in the mineral concentration process to be low.

scholarly journals ANALISIS PENGARUH LAJU PUTAR TERHADAP KOROSI BAJA KARBON API 5LX65 MENGGUNAKAN METODE ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY

2012 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Agus Solehudin ◽  
Asep Lukman
Keyword(s):  
Electron Microscope ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Scanning Electron Microscope ◽  
Energy Dispersive Spectroscopy ◽  
Electrochemical Impedance ◽  
Energy Dispersive ◽  
X Ray ◽  
Scanning Electron

Pada percobaan ini, telah dipelajari pengaruh laju putar terhadap laju korosi baja karbon API 5LX65 yang direndam selama 24 jam dalam larutan NaCl 3,5% + 500 mg/L H2S menggunakan metode EIS (Electrochemical Impedance Spectroscopy) pada suhu 50oC dan pH 4 dengan variasi laju putar 50 rpm, 150 rpm, dan 250 rpm. Hasil percobaan memperlihatkan pergeseran dan penyempitan kurva setengah lingkaran impedansi imaginer terhadap impedansi real, dengan meningkatnya laju putar dari 50 rpm sampai dengan 250 rpm. Hal ini mengindikasikan bahwa aktifitas pelarutan baja meningkat dengan percepatan laju putar. Nilai Cdl meningkat dengan meningkatnya laju putar. Nilai tahanan polarisasi (Rp) semakin menurun dengan meningkatnya laju putar, sementara nilai tahanan larutan (Rs) relatif tidak berubah. Potensial korosi pada laju putar 50 rpm, 150 rpm dan 250 rpm stabil  pada -517 mV hingga -508 mV terhadap Ag/AgCl. Gabungan pengamatan Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS) dan X-Ray Diffractomer (XRD) menunjukkan terbentuknya lapisan produk korosi. Hasil analisis XRD spesimen uji yang dikorosikan pada suhu 50oC selama 24 jam menunjukkan bahwa lapisan produk korosi mengandung besi sulfida (FeS). Morfologi permukaan spesimen ini memperlihatkan adanya korosi sumuran.Kata kunci: laju putar, korosi, baja karbon, EIS, H2S

Sign in / Sign up

Export Citation Format

Share Document