Effect of Heating Rate on the Development of Annealing Texture in Nonoriented Electrical Steels

The core loss and magnetic induction of electrical steels are dependent on the microstructure and texture of the material, which are produced by the thermo-mechanical processing. After a conventional rolling process, crystal orientations of the α-(//RD) and γ-(//ND) fibers are strongly present in the final texture. These fibers have a drastically negative effect on the magnetic properties of electrical steels. By applying asymmetric rolling, significant shear strains could be introduced across the thickness of the sheet and thus a deformation texture with more magnetically favorable components is expected. In this study, an electrical steel of 1.23 wt.% Si was subjected to asymmetric warm rolling in a rolling mill with different roll diameters. The evolutions of both deformed and annealed textures were investigated. The texture evolution during asymmetric warm rolling was analyzed by crystal plasticity simulations using the ALAMEL model. A good fit between measured and calculated textures was obtained. The annealing texture could be understood in terms of an oriented nucleation model that selects crystal orientations with a lower than average stored energy of plastic deformation.

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Effect of Heating Rate on the Development of Annealing Texture in a 1.09 wt.% Si Non-oriented Electrical Steel

ISIJ International ◽

10.2355/isijinternational.isijint-2015-455 ◽

2016 ◽

Vol 56 (2) ◽

pp. 326-334 ◽

Cited By ~ 5

Author(s):

Shu-Yu Wu ◽

Chun-Hung Lin ◽

Wei-Chih Hsu ◽

Liuwen Chang ◽

Pei-Ling Sun ◽

...

Keyword(s):

Heating Rate ◽

Electrical Steel ◽

Annealing Texture

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The Influence of Thin Nickel Coatings on the Goss-Texture Development in Iron–3% Silicon

Textures and Microstructures ◽

10.1155/tsm.11.187 ◽

1989 ◽

Vol 11 (2-4) ◽

pp. 187-202

Author(s):

P. Gangli ◽

K. Lücke

Keyword(s):

Grain Boundaries ◽

Heating Rate ◽

Grain Growth ◽

Final Anneal ◽

Texture Development ◽

Goss Texture ◽

Electrical Steels ◽

Nickel Coatings ◽

Precipitation Characteristics ◽

Thin Nickel

Microstructure and texture (ODF) investigations were carried out on Fe–3% Si electrical steels with different C, MnS and AlN content (CGO and HGO quality). The main result was that by a thin (0.25 μm) Ni layer on the sheet surfaces produced by electroplating before the final anneal the starting temperature of discontinuous grain growth could be decreased and the Goss texture could be sharpened. This effect was influenced by the heating rate and disappeared after decarburization. It is caused by the diffusion of Ni along the grain boundaries by which the segregation and precipitation characteristics of elements like C, N, S, is changed.

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A TEM study of the influence of microstructure on the superplastic behavior of a U-5.8 wt.% Nb alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144310 ◽

1986 ◽

Vol 44 ◽

pp. 568-569

Author(s):

G. Mackiewicz Ludtka

Keyword(s):

Grain Size ◽

Heating Rate ◽

Phase Field ◽

Single Phase ◽

Superplastic Behavior ◽

Two Phase ◽

Single Phase Field

Historically, metals exhibit superplasticity only while forming in a two-phase field because a two-phase microstructure helps ensure a fine, stable grain size. In the U-5.8 Nb alloy, superplastici ty exists for up to 2 h in the single phase field (γ1) at 670°C. This is above the equilibrium monotectoid temperature of 647°C. Utilizing dilatometry, the superplastic (SP) U-5.8 Nb alloy requires superheating to 658°C to initiate the α+γ2 → γ1 transformation at a heating rate of 1.5°C/s. Hence, the U-5.8 Nb alloy exhibits an anomolous superplastic behavior.

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The microstructure change of low-carbon electrical steels by residual aluminum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153403 ◽

1989 ◽

Vol 47 ◽

pp. 286-287

Author(s):

C.K. Hou ◽

C.T. Hu ◽

Sanboh Lee

Keyword(s):

Annealing Treatment ◽

Low Carbon ◽

Electrical Steels ◽

Vacuum Degassing ◽

Spherical Inclusions ◽

Residual Aluminum ◽

Average Grain Size ◽

The Matrix ◽

Fine Size ◽

To Come

The fully processed low-carbon electrical steels are generally fabricated through vacuum degassing to reduce the carbon level and to avoid the need for any further decarburization annealing treatment. This investigation was conducted on eighteen heats of such steels with aluminum content ranging from 0.001% to 0.011% which was believed to come from the addition of ferroalloys.The sizes of all the observed grains are less than 24 μm, and gradually decrease as the content of aluminum is increased from 0.001% to 0.007%. For steels with residual aluminum greater than 0. 007%, the average grain size becomes constant and is about 8.8 μm as shown in Fig. 1. When the aluminum is increased, the observed grains are changed from the uniformly coarse and equiaxial shape to the fine size in the region near surfaces and the elongated shape in the central region. SEM and EDAX analysis of large spherical inclusions in the matrix indicate that silicate is the majority compound when the aluminum propotion is less than 0.003%, then the content of aluminum in compound inclusion increases with that in steel.

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Effect of solute carbon present during cold rolling and annealing on the magnetic properties of electrical steels

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:19982111 ◽

1998 ◽

Vol 08 (PR2) ◽

pp. Pr2-483-Pr2-486 ◽

Cited By ~ 1

Author(s):

K. Eloot ◽

J. Penning ◽

J. Dilewijns

Keyword(s):

Magnetic Properties ◽

Cold Rolling ◽

Electrical Steels ◽

Cold Rolling And Annealing ◽

Solute Carbon

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Optimization of the time the chromatograph thermostats exit to a given temperature

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-6-40-45 ◽

2020 ◽

pp. 40-45

Author(s):

Nadezhda O. Vzduleva ◽

Valery B. Gitlin

Keyword(s):

Heating Rate ◽

Entire Range ◽

Gas Chromatograph ◽

Heating And Cooling ◽

Operating Temperatures ◽

The Stability

The problems of ensuring the stability of the temperature of the chromatographic experiment carried out using a serial gas chromatograph LGH-3000 are considered. Limiting the permissible heating rate of the chromatograph thermostats does not allow a quick transition to the new conditions of the chromatographic experiment in accordance with the requirements of the technical conditions. The processes of heating and cooling the thermostat are analyzed. It is shown that the ratio of the duration of the interval equal to the sum of the durations of the heating and cooling intervals to the duration of the heating interval is inversely proportional to the temperature of the chromatographic experiment. Based on this situation, an empirical algorithm is proposed for heating the thermostat to a given temperature, which made it possible to reduce the time it takes to reach a given temperature in the entire range of operating temperatures.

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