scholarly journals Determining the effect of grain size and maximum induction upon coercive field of electrical steels

2011 ◽  
Vol 323 (18-19) ◽  
pp. 2335-2339 ◽  
Author(s):  
Fernando José Gomes Landgraf ◽  
João Ricardo Filipini da Silveira ◽  
Daniel Rodrigues-Jr.
Keyword(s):  
Grain Size ◽  
Coercive Field ◽  
Electrical Steels ◽  
Maximum Induction

Effect of Fast Annealing on Microstructure and Mechanical Properties of Non-Oriented Al-Si Low C Electrical Steels

2007 ◽  
Vol 560 ◽  
pp. 29-34 ◽  
Author(s):  
Emmanuel Gutiérrez C. ◽  
Armando Salinas-Rodríguez ◽  
Enrique Nava-Vázquez
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Room Temperature ◽  
Tensile Tests ◽  
Rate Of Change ◽  
Uniaxial Tensile ◽  
Electrical Steels ◽  
Offset Yield Strength ◽  
Microstructure And Mechanical Properties ◽  
Increasing Temperature

The effects of heating rate and annealing temperature on the microstructure and mechanical properties of cold rolled Al-Si, low C non-oriented electrical steels are investigated using SEM metallography and uniaxial tensile tests. The experimental results show that short term annealing at temperatures up to 850 °C result in microstructures consisting of recrystallized ferrite grains with sizes similar to those observed in industrial semi-processed strips subjected to long term batch annealing treatments. Within the temperature range investigated, the grain size increases and the 0.2% offset yield strength decreases with increasing temperature. It was observed that the rate of change of grain size with increasing temperature increases when annealing is performed at temperatures greater than Ac1 (~870 °C). This effect is attributed to Fe3C dissolution and rapid C segregation to austenite for annealing temperatures within the ferrite+austenite phase field. This leads to faster ferrite growth and formation of pearlite when the steel is finally cooled to room temperature. The presence of pearlite at room temperature decreases the ductility of samples annealed at T > Ac1.

Improving magnetic properties of non-oriented electrical steels by controlling grain size prior to cold rolling

2019 ◽  
Vol 491 ◽  
pp. 165636 ◽  
Author(s):  
Ling-Zi An ◽  
Yin-ping Wang ◽  
Hong-Yu Song ◽  
Guo-Dong Wang ◽  
Hai-Tao Liu
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Cold Rolling ◽  
Electrical Steels

Texture and Microstructure Evolution during Box Annealing of a Non-Oriented-Grain Electrical Steel

2011 ◽  
Vol 702-703 ◽  
pp. 595-598
Author(s):  
Francisco N.C. Freitas ◽  
Manoel Ribeiro da Silva ◽  
Sergio S.M. Tavares ◽  
Hamilton F.G. Abreu
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Cold Rolling ◽  
Crystallographic Texture ◽  
Electrical Steel ◽  
Electron Backscatter Diffraction ◽  
Magnetization Direction ◽  
Electrical Steels ◽  
Cold Rolling And Annealing ◽  
Work Samples

Non-oriented grain type electrical steels are used mainly in electrical rotating machines such as motors and compressors, in which the magnetization direction rotates 360 ° every cycle while remaining in the plane of the plate. The performance of these devices is affected by crystallographic texture of electrical steels due to strong anisotropy of magnetic properties. The electrical steel is supplied in the form of plates which are processed by cold rolling and subsequent annealing. Both, cold rolling and annealing directly influence the formation of crystallographic texture components. During annealing, recrystallization occurs, and this phenomenon gives rise to changes in texture that influences the quality of the final product and its application. Several works have been published in the study of the evolution of crystallographic texture and grain size in this type of electrical steel. In this work, samples have been taken in industrial conditions at various temperatures during the annealing in a coil box. Electrical steel samples cold rolled with reductions of 50% and 70% in thickness were removed during the process of annealing, and the evolution of texture with increasing temperature was studied. Aspects related to recrystallization, grain size and the evolution of texture and magnetic properties were discussed. Texture and recrystallization were studied by X-ray diffraction and electron backscatter diffraction (EBSD). The magnetic properties were measured in a vibrating sample magnetometer.

0.75SrBi2Ta2O9-0.25Bi3TiTaO9 Layered Structural Thin Films: Microstructure and Ferroelectric Properties

2008 ◽  
Vol 368-372 ◽  
pp. 1814-1816
Author(s):  
Dan Xie ◽  
Zhi Gang Zhang ◽  
Tian Ling Ren ◽  
Li Tian Liu
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Grain Size ◽  
Coercive Field ◽  
Remanent Polarization ◽  
Ferroelectric Properties ◽  
Significant Enhancement ◽  
Solution Deposition ◽  
Annealing Temperatures

{0.75SrBi2Ta2O9-0.25Bi3TiTaO9}(SBT-BTT) thin films were prepared by the modified metalorganic solution deposition (MOSD) technique. The microstructure and ferroelectric properties of SBTBTT thin films were studied. The SBT-BTT thin films were produced at 750°C. The grain size and surface roughness of SBT-BTT films showed significant enhancement with an increase in annealing temperatures. It is found that SBT-BTT thin films have good ferroelectric properties. The measured remanent polarization values for SBT-BTT, SBT and BTT capacitors were 15, 7.5 and 4.8μC/cm2, respectively. The coercive field for SBT-BTT capacitors was 50kV/cm. More importantly, the polarization of SBT-BTT capacitors only decreased 5% after 1011 switching cycles at a frequency of 1MHz.

Control of Grain Size of Pb(Zr,Ti)O3 Thin Films by MOCVD and the Effect of Size on the Electrical Properties

1998 ◽  
Vol 541 ◽  
Author(s):  
H. Fujisawa ◽  
S. Nakashima ◽  
M. Shimizu ◽  
H. Niu
Keyword(s):  
Thin Films ◽  
Growth Rate ◽  
Grain Size ◽  
Electrical Properties ◽  
Coercive Field ◽  
Remanent Polarization ◽  
Dielectric Constants ◽  
Pzt Thin Films ◽  
Pzt Films

AbstractThe grain size of MOCVD-Pb(Zr,Ti)O3 (PZT) thin films was successfully controlled by changing the grain size of Ir bottom electrodes and by changing the growth rate of PZT films. In Ir/PZT/Ir/SiO2/Si capacitors, the grain size of PZT thin films increased from 120 to 240nm as the grain size of bottom Ir electrodes increased from 50 to 200nm. The dielectric constants of PZT thin films increased from 760 to 1440 as the grain size increased from 120 to 240nm. Remanent polarization increased and coercive field decreased as the grain size increased. This dependence of electrical properties on the grain size coincided with that of ceramics.

scholarly journals Integrated Process Simulation of Non-Oriented Electrical Steel

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6659
Author(s):  
Anett Stöcker ◽  
Max Weiner ◽  
Grzegorz Korpała ◽  
Ulrich Prahl ◽  
Xuefei Wei ◽  
...  
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Cold Rolling ◽  
Process Parameters ◽  
Hot Rolling ◽  
Electrical Steel ◽  
Sheet Thickness ◽  
Electrical Steels ◽  
Heterogeneous Microstructures ◽  
The Impact

[d=A]A tailor-made microstructure, especially regarding grain size and texture, improves the magnetic properties of non-oriented electrical steels. One way to adjust the microstructure is to control the production and processing in great detail. Simulation and modeling approaches can help to evaluate the impact of different process parameters and finally select them appropriately. We present individual model approaches for hot rolling, cold rolling, annealing and shear cutting and aim to connect the models to account for the complex interrelationships between the process steps. A layer model combined with a microstructure model describes the grain size evolution during hot rolling. The crystal plasticity finite-element method (CPFEM) predicts the cold-rolling texture. Grain size and texture evolution during annealing is captured by the level-set method and the heat treatment model GraGLeS2D+. The impact of different grain sizes across the sheet thickness on residual stress state is evaluated by the surface model. All models take heterogeneous microstructures across the sheet thickness into account. Furthermore, a relationship is established between process and material parameters and magnetic properties. The basic mathematical principles of the models are explained and demonstrated using laboratory experiments on a non-oriented electrical steel with 3.16 wt.% Si as an example. Improving the magnetic properties of non-oriented electrical steels are of high interest. In this context, improvement by a tailor-made microstructure, especially regarding grain size and texture, is one focus. One way to adjust the microstructure is to control the production and processing in great detail. Simulation and modeling approaches, emphasizing grain size and texture development, can help to evaluate and finally set process parameters. Here, we present individual model approaches for hot rolling, cold rolling, annealing and shear cutting and aim to connect the models to account for the complex interrelationships between the process steps. Furthermore, a connection between the process parameters and the magnetic properties is drawn. Grain size, grain size distribution, texture and dislocation density are the main transfer parameters in between the models. All models take heterogeneous microstructures across the sheet thickness into account. The basic mathematical principles of the models are explained, and a case study is presented in each case using FeSi3.2wt%Si as an example material.

scholarly journals Material Design for Low-Loss Non-Oriented Electrical Steel for Energy Efficient Drives

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6588
Author(s):  
Nora Leuning ◽  
Markus Jaeger ◽  
Benedikt Schauerte ◽  
Anett Stöcker ◽  
Rudolf Kawalla ◽  
...  
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Electrical Steel ◽  
Sheet Thickness ◽  
Material Design ◽  
Material Behavior ◽  
Nonlinear Material ◽  
Design Stage ◽  
Electrical Machine ◽  
Electrical Steels

Due to the nonlinear material behavior and contradicting application requirements, the selection of a specific electrical steel grade for a highly efficient electrical machine during its design stage is challenging. With sufficient knowledge of the correlations between material and magnetic properties and capable material models, a material design for specific requirements can be enabled. In this work, the correlations between magnetization behavior, iron loss and the most relevant material parameters for non-oriented electrical steels, i.e., alloying, sheet thickness and grain size, are studied on laboratory-produced iron-based electrical steels of 2.4 and 3.2 wt % silicon. Different final thicknesses and grain sizes for both alloys are obtained by different production parameters to produce a total of 21 final material states, which are characterized by state-of-the-art material characterization methods. The magnetic properties are measured on a single sheet tester, quantified up to 5 kHz and used to parametrize the semi-physical IEM loss model. From the loss parameters, a tailor-made material, marked by its thickness and grain size is deduced. The influence of different steel grades and the chance of tailor-made material design is discussed in the context of an exemplary e-mobility application by performing finite-element electrical machine simulations and post-processing on four of the twenty-one materials and the tailor-made material. It is shown that thicker materials can lead to fewer iron losses if the alloying and grain size are adapted and that the three studied parameters are in fact levers for material design where resources can be saved by a targeted optimization.

Influence of Thickness on Magnetic and Microstructural Properties in Electrical Steels Semi-Processed of Low Efficiency

2018 ◽  
Vol 930 ◽  
pp. 466-471
Author(s):  
M.A. Trindade ◽  
Marcos Flavio de Campos ◽  
Fernando José Gomes Landgraf ◽  
Nelson Batista de Lima ◽  
A. Almeida
Keyword(s):  
Heat Treatment ◽  
Grain Size ◽  
Magnetic Properties ◽  
Silicon Content ◽  
Static Condition ◽  
Magnetic Losses ◽  
Microstructural Properties ◽  
Electrical Steels ◽  
Wet Heat ◽  
Low Efficiency

In this study, a steel for semiprocessed electrical purposes of non-oriented grain with approximately 0.05% carbon content and 0.02% silicon content was evaluated. Lamellas with kind of thicknesses 0.58 mm, 0,66 mm and 0.87 mm were processed on an industrial scale with a strain rate in the hardening lamination between 3 and 5%. The magnetic properties were evaluated after the wet heat treatment. The loss separation method was applied, estimating the hysteretic plot with hysteresis measure in the quasi static condition and the parasitic losses calculated according to Thomson's Equation. By increasing grain size, permeability increases and coercivity decreases. However, in the case of losses, there is an optimum grain size. After the procedure of separation of losses, it was observed that increase of thickness results in increase of the anomalous parcel of magnetic losses.

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