scholarly journals Effect of Normalizing Annealing Temperature on Precipitates and Texture of Nb-Cr-Bearing Decarburized Grain-Oriented Silicon Steels

Metals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 457 ◽  
Author(s):  
Yulong Liu ◽  
Chengyi Zhu ◽  
Juan Jia ◽  
Yong Wang ◽  
Yu Liu ◽  
...  
Keyword(s):  
Lattice Theory ◽  
Annealing Temperature ◽  
Coincidence Site Lattice ◽  
Secondary Recrystallization ◽  
Number Density ◽  
Goss Texture ◽  
Different Temperatures ◽  
Mean Size ◽  
Evolution Of Precipitates ◽  
Normalizing Annealing

The evolution of precipitates and texture was investigated in Nb-Cr-bearing decarburized specimens after normalizing at different temperatures. Enough inhibitors, including Nb(C,N), were obtained, of 20~40 nm in size. Increasing normalizing annealing temperature leads to the number density of the precipitates decreasing and that of mean size increasing. The Goss texture content in the decarburized specimens decreases in different degrees compared with the normalized ones. The minimum Goss texture and maximum ∑9 grain boundaries were obtained in the decarburized specimen normalizing at 950 °C and in this specimen, enough fine dispersed inhibitors, weak but relative stable Goss texture and uniform grain size will be beneficial for Goss grains growth in secondary recrystallization, according to the coincidence site lattice theory.

Recrystallization Law of Ti-IF Steel During Annealing Process

2011 ◽  
Vol 399-401 ◽  
pp. 2301-2304
Author(s):  
Yan Qing Feng ◽  
Zhi Guo Gao ◽  
Fu Ming Wang
Keyword(s):  
Annealing Temperature ◽  
Secondary Recrystallization ◽  
Annealing Process ◽  
Recrystallization Temperature ◽  
Continuous Annealing ◽  
If Steel ◽  
Effect Factor ◽  
Batch Annealing ◽  
Main Effect ◽  
Different Temperatures

Recrystallization law was investigated at different annealing processes. The results showed that the annealing temperature was a main effect factor on the properties of Ti-IF steel. Nominal recrystallization temperature of the samples was evaluated as 620 °C. Simulated batch annealing was performed by two-stage heating. Determined recrystallization temperature was 660 °C, the recrystallization of samples heated at 660 °C was completed in 68min. For 800 °C, the equiaxial recrystallized grains were obtained. Simulated continuous annealing by rapidly heating to different temperatures, samples were held for 100s and then cooled in air. Recrystallization nucleation was not observed until 660 °C. The occurrence of secondary recrystallization was observed at 900 °C.

scholarly journals Influence of Temperature on Typical Texture Distribution in Primary Recrystallization Matrix of 3% Si CGO Silicon Steel

2016 ◽  
Vol 2016 ◽  
pp. 1-6
Author(s):  
Zhi-chao Li ◽  
Ning Dang ◽  
Zhen-li Mi
Keyword(s):  
Grain Boundaries ◽  
Annealing Temperature ◽  
Secondary Recrystallization ◽  
Fiber Texture ◽  
Primary Recrystallization ◽  
Silicon Steel ◽  
Recrystallization Annealing ◽  
Intermediate Annealing ◽  
High Angle ◽  
Goss Texture

OM (optical microscopy) and EBSD (electron backscatter diffraction) techniques were used to study microstructure and texture distribution during primary recrystallization under different intermediate annealing temperatures in CGO silicon steels. The effect of intermediate annealing temperature on texture distribution in 3% Si electrical steel was analyzed. The results indicate that the microstructure in primary recrystallization matrix of CGO silicon steel is comprised of equiaxed ferrite grains. Mean grain size of primary recrystallization increases with the rising of intermediate annealing temperature.γ-fiber texture is the dominant component in primary recrystallization matrix. With higher intermediate annealing temperature,111121texture and111110texture increase and111121texture is stronger than111110texture. Goss texture was observed to be decreased firstly and then increased. The content of high angle grain boundaries in primary recrystallization matrix are affected by intermediate annealing temperature. When intermediate annealing temperature is increased, high angle grain boundaries are increased firstly and then decreased. Misorientation distribution in primary recrystallized matrix is affected by primary recrystallization annealing temperature either. The content of high angle grain boundaries are increased owing to higher primary recrystallization annealing temperature, which can be a benefit to the abnormal growth of Goss grains in secondary recrystallization.

scholarly journals The effect of Nb content on precipitates, microstructure and texture of grain oriented silicon steel

2019 ◽  
Vol 38 (2019) ◽  
pp. 628-638 ◽  
Author(s):  
Yong Wang ◽  
Chengyi Zhu ◽  
Guangqiang Li ◽  
Yu Liu ◽  
Bowen Zhou
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
Hot Rolling ◽  
Silicon Steel ◽  
Pinning Force ◽  
Number Density ◽  
Goss Texture ◽  
Treatment Processes ◽  
Nb Content ◽  
Evolution Of Precipitates

AbstractNiobium has the potential as an inhibitor forming element in grain oriented silicon steel. The grain oriented silicon steels with different Nb contents (0.028 wt% and 0.052 wt%) were prepared, and the effect of Nb content on the evolution of precipitates, microstructure and texture were investigated by the various analysis methods and thermodynamic calculations. The results show that the smaller size and larger number density of precipitates were obtained in the sample with low Nb steel after hot rolling. In the process of normalization, Nb(C, N) are more inclined to precipitate along the dislocations caused by hot rolling, contributing to finer and more dispersed precipitates in normalized bands. The finer and more dispersed precipitates in 0.028% Nb containing silicon steel perform a stronger pinning force during whole heat treatment processes, resulting in the smaller grain size and higher intensity of Goss texture in the specimen containing 0.028%Nb. After normalization, the intensities of Goss texture in both steels decrease.

Microstructural Evolution of Ni-doped Ferritic/martensitic Steels Irradiated in the HFIR

2000 ◽  
Vol 650 ◽  
Author(s):  
Naoyuki Hashimoto ◽  
Ronald L. Klueh ◽  
Janet P. Robertson
Keyword(s):  
Dislocation Density ◽  
Microstructural Evolution ◽  
Dislocation Loops ◽  
Number Density ◽  
Martensitic Steels ◽  
Different Temperatures ◽  
Mean Size ◽  
Radiation Induced ◽  
Lath Width ◽  
The Mean

ABSTRACTThe microstructures of reduced-activation ferritic/martensitic steels, 9Cr-2WVTa and 9Cr-2WVTa doped with 2% Ni, irradiated at 400oC up to 12 dpa in the High Flux Isotope Reactor (HFIR), were investigated by transmission electron microscopy. Specimens were tempered at two different temperatures in order to investigate the effects of tempering on microstructural evolution during irradiation. Before irradiation, the lath width of Ni-doped 9Cr-2WVTa was somewhat narrower and the dislocation density tended to be higher compared with 9Cr-2WVTa. Dislocation density of specimens tempered at 750°C was lower than that tempered at 700°C. In all steels, precipitates on grain and/or lath boundaries were mainly M23C6, and there were a few TaC along dislocations in the matrices. Irradiation-induced cavities were observed in all the steels. The cavity number density of the Ni-doped 9Cr-2WVTa was higher than that of 9Cr-2WVTa due to the higher concentration of helium; however, swelling in each steels was < 0.1% because cavity sizes were so small. There was no difference of cavity number density between the steels tempered at 700°C and 750°C, but the mean size of the cavities in the steels tempered at 750°C was larger than that tempered at 700°C. Irradiation-induced a0<100> and (a0/2)<111> type dislocation loops were observed in all steels; number density and mean diameter of a0<100> type loops was higher and larger than that of (a0/2)<111> type loops. There was a tendency for the number density of loops in Ni-doped 9Cr-2WVTa to be slightly higher than that in 9Cr-2WVTa. In addition, the mean size of loops in the steels tempered at 750°C was larger than for those tempered at 700°C, while there was not much difference of number density between them. In the steels doped with Ni, irradiation-produced precipitates, identified as M6C(η)-type carbide, were found in the matrices. In this experiment, the change in tensile properties and the δDBTT of the 9Cr-2VWTa-2Ni was greater than for 9Cr-2WVTa. The microstructural evidence suggests that these differences in mechanical behavior are related to the formation of radiation-induced precipitates and cavities in the Ni-doped alloy; further analysis of the data using barrier hardening models is in progress.

scholarly journals Influence of Cu on the Improvement of Magnetic Properties and Structure of L10 FePt Nanoparticles

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1097
Author(s):  
Luran Zhang ◽  
Xinchen Du ◽  
Hongjie Lu ◽  
Dandan Gao ◽  
Huan Liu ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Annealing Temperature ◽  
Reduction Method ◽  
Solid Phase ◽  
Average Particle Size ◽  
Fept Nanoparticles ◽  
Average Particle ◽  
Phase Reduction ◽  
Different Temperatures ◽  
One Step

L10 ordered FePt and FePtCu nanoparticles (NPs) with a good dispersion were successfully fabricated by a simple, green, one-step solid-phase reduction method. Fe (acac)3, Pt (acac)2, and CuO as the precursors were dispersed in NaCl and annealed at different temperatures with an H2-containing atmosphere. As the annealing temperature increased, the chemical order parameter (S), average particle size (D), coercivity (Hc), and saturation magnetization (Ms) of FePt and FePtCu NPs increased and the size distribution range of the particles became wider. The ordered degree, D, Hc, and Ms of FePt NPs were greatly improved by adding 5% Cu. The highest S, D, Hc, and Ms were obtained when FePtCu NPs annealed at 750 °C, which were 0.91, 4.87 nm, 12,200 Oe, and 23.38 emu/g, respectively. The structure and magnetic properties of FePt and FePtCu NPs at different annealing temperatures were investigated and the formation mechanism of FePt and FePtCu NPs were discussed in detail.

scholarly journals Optimizing the Properties of La0.8Sr0.2CrO3 Thin Films through Post-Annealing for High-Temperature Sensing

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1802
Author(s):  
Dan Liu ◽  
Peng Shi ◽  
Yantao Liu ◽  
Yijun Zhang ◽  
Bian Tian ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Annealing Temperature ◽  
Rf Sputtering ◽  
Maximum Size ◽  
Cross Sectional ◽  
Post Annealing ◽  
Maximum Conductivity ◽  
Different Temperatures ◽  
Post Annealing Temperature

La0.8Sr0.2CrO3 (0.2LSCO) thin films were prepared via the RF sputtering method to fabricate thin-film thermocouples (TFTCs), and post-annealing processes were employed to optimize their properties to sense high temperatures. The XRD patterns of the 0.2LSCO thin films showed a pure phase, and their crystallinities increased with the post-annealing temperature from 800 °C to 1000 °C, while some impurity phases of Cr2O3 and SrCr2O7 were observed above 1000 °C. The surface images indicated that the grain size increased first and then decreased, and the maximum size was 0.71 μm at 1100 °C. The cross-sectional images showed that the thickness of the 0.2LSCO thin films decreased significantly above 1000 °C, which was mainly due to the evaporation of Sr2+ and Cr3+. At the same time, the maximum conductivity was achieved for the film annealed at 1000 °C, which was 6.25 × 10−2 S/cm. When the thin films post-annealed at different temperatures were coupled with Pt reference electrodes to form TFTCs, the trend of output voltage to first increase and then decrease was observed, and the maximum average Seebeck coefficient of 167.8 µV/°C was obtained for the 0.2LSCO thin film post-annealed at 1100 °C. Through post-annealing optimization, the best post-annealing temperature was 1000 °C, which made the 0.2LSCO thin film more stable to monitor the temperatures of turbine engines for a long period of time.

scholarly journals Effect of Mn Content and Solution Annealing Temperature on the Corrosion Resistance of Stainless Steel Alloys

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Ihsan-ul-Haq Toor
Keyword(s):  
Corrosion Resistance ◽  
Annealing Temperature ◽  
Electrochemical Impedance ◽  
Austenitic Stainless Steels ◽  
Electrochemical Tests ◽  
Linear Polarization Resistance ◽  
Ni Content ◽  
Different Temperatures ◽  
Acidic Chloride ◽  
Mn Content

The corrosion behavior of two specially designed austenitic stainless steels (SSs) having different Nickel (Ni) and Manganese (Mn) contents was investigated. Prior to electrochemical tests, SS alloys were solution-annealed at two different temperatures, that is, at 1030°C for 2 h and 1050°C for 0.5 h. Potentiodynamic polarization (PD) tests were carried out in chloride and acidic chloride, whereas linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) was performed in 0.5 M NaCl solution at room temperature. SEM/EDS investigations were carried out to study the microstructure and types of inclusions present in these alloys. Experimental results suggested that the alloy with highest Ni content and annealed at 1050°C/0.5 hr has the highest corrosion resistance.

scholarly journals Photocatalytic Activity and Optical Properties of Blue Persistent Phosphors under UV and Solar Irradiation

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
C. R. García ◽  
L. A. Diaz-Torres ◽  
J. Oliva ◽  
M. T. Romero ◽  
P. Salas
Keyword(s):  
Photocatalytic Activity ◽  
Annealing Temperature ◽  
Uv Light ◽  
Solar Irradiation ◽  
Photoluminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Water Cleaning ◽  
Different Temperatures ◽  
The Eu

Blue phosphorescent strontium aluminosilicate powders were prepared by combustion synthesis route and a postannealing treatments at different temperatures. X-ray diffraction analysis showed that phosphors are composed of two main hexagonal phases: SrAl2O4and Sr3Al32O51. The morphology of the phosphors changed from micrograins (1000°C) to a mixture of bars and hexagons (1200°C) and finally to only hexagons (1300°C) as the annealing temperature is increased. Photoluminescence spectra showed a strong blue-green phosphorescent emission centered atλem=455 nm, which is associated with4f65d1→4f6  (8S7/2)transition of the Eu2+. The sample annealed at 1200°C presents the highest luminance value (40 Cd/m2) with CIE coordinates (0.1589, 0.1972). Also, the photocatalytic degradation of methylene blue (MB) under UV light (at 365 nm) was monitored. Samples annealed at 1000°C and 1300°C presented the highest percentage of degradation (32% and 38.5%, resp.) after 360 min. In the case of photocatalytic activity under solar irradiation, the samples annealed at 1000°C, 1150°C, and 1200°C produced total degradation of MB after only 300 min. Hence, the results obtained with solar photocatalysis suggest that our powders could be useful for water cleaning in water treatment plants.

Ajustement par recuits rapides RTA (rapid thermal annealing) des contraintes dans des couches minces de tungstène utilisées comme absorbant pour des masques à rayons X

1991 ◽  
Vol 69 (3-4) ◽  
pp. 451-455 ◽  
Author(s):  
H. Lafontaine ◽  
J. F. Currie ◽  
S. Boily ◽  
M. Chaker ◽  
H. Pépin
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Annealing Temperature ◽  
Rf Power ◽  
X Ray ◽  
Stress Changes ◽  
Different Temperatures ◽  
Absorbing Layer ◽  
Good Agreement ◽  
Sputtering System

Tungsten thin films are deposited with a triode sputtering system in order to obtain an absorbing layer for X-ray masks. The mechanical stress is studied as a function of different pressure and RF power conditions during deposition. Rapid thermal annealing at different temperatures and durations is performed in order to produce films under low compressive stress. We observe that the stress changes occur over the time scale of seconds at the annealing temperature and that the corresponding activation energies are low (60 meV). Grain growth in a preferred orientation explains the observed changes in stress. The magnitude in the change of stress is in good agreement with a model proposed by Hoffman et al. relating the stress to grain size and grain boundary dimensions. [Journal translation]

Optical Modeling of Gold nanoparticles (Au NP) for efficiency improvement of a-Si:H photovoltaic cells

2014 ◽  
Vol 1671 ◽  
Author(s):  
Peiqing Yu ◽  
Jean-Philippe Blondeau ◽  
Caroline Andreazza ◽  
Esidor Ntsoenzok ◽  
Julien Roussel ◽  
...  
Keyword(s):  
Annealing Temperature ◽  
Surface Coverage ◽  
Thermal Evaporation ◽  
Active Material ◽  
Optical Path Length ◽  
Localized Surface Plasmon ◽  
Optical Modeling ◽  
Mean Size ◽  
Refractive Medium ◽  
Uv Visible

ABSTRACTThe efficiency of thin-film solar cells using a-Si:H is limited by the decrease in a-Si:H layer optical path length and its poor light absorption at red and NIR wavelengths. Metal NP such as Au have been shown to increase the absorption in the active material and then cell performances, by exhibiting localized surface plasmon (LSP) resonances. Our work’s goal is to understand NP influence in such cells, to perform an optimal structure by increasing the amount of light absorbed within the cell using NP scattering and luminescence. Modeling based on Mie theory is first carried out using bulk Palik data for Au spheres with various diameters and refractive medium indexes. Using modeling parameters, Au layers were deposited on glass and SnO2 substrates respectively by thermal evaporation in vacuum and sputtering, followed by thermal annealing (200 ∼ 500°C) in order to promote the NP growth. MEB pictures show quasispherical Au NP shape with a mean size of 150nm. This diameter range switches extinction of NP in scattering regime. Annealing temperature (T) strongly affects the NP morphology. Surface coverage decreases and sphericity appears to increase with T. UV-Visible spectroscopy displays distinct LSP resonances around 600nm after annealing with a red shift while T increases.

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