scholarly journals Effect of a High Magnetic Field on Eutectoid Point Shift and Texture Evolution in 0.81C-Fe Steel

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Y.D. Zhang ◽  
C. Esling ◽  
M. Calcagnotto ◽  
M.L. Gong ◽  
H. Klein ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Texture Evolution ◽  
Transverse Field ◽  
Dipolar Interaction ◽  
Statistical Thermodynamic ◽  
Field Calculation ◽  
Eutectoid Temperature ◽  
Pole Figures ◽  
Magnetic Dipolar Interaction ◽  
The Magnetic Field

A 12 T magnetic field has been applied to the annealing process of a 0.81%C-Fe (wt.%). It is found that the magnetic field shifts the eutectoid carbon content from 0.77 wt.% to 0.83 wt.%. The statistical thermodynamic calculations were performed to calculate the eutectoid temperature change by the magnetic field. Calculation shows that the increase of the eutectoid temperature by a 12 T field is 29∘C. Synchrotron radiation measurements were performed to measure the pole figures of the samples and were analyzed by MAUD to determine the bulk texture of the ferrite phase In the field-treated and non field-treated samples. Results show that although there is no specific preferred orientation appearing by applying the magnetic field, slight enhancement of (001) fiber component occurs in both the sample normal direction (ND) and the transverse direction (TD). This effect might be related to the magnetic dipolar interaction between Fe atoms in the transverse field direction.

Effects of Magnetic Field Intensity on Microstructure and Orientation of Proeutectoid Ferrite in Fe-C Alloy

2012 ◽  
Vol 706-709 ◽  
pp. 2680-2684
Author(s):  
Xiao Xue Zhang ◽  
Yu Dong Zhang ◽  
Shou Jing Wang ◽  
Claude Esling ◽  
Xiang Zhao ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Crystallographic Orientation ◽  
Magnetic Field Intensity ◽  
Dipolar Interaction ◽  
Field Direction ◽  
Magnetic Dipolar Interaction ◽  
Proeutectoid Ferrite ◽  
The Magnetic Field

The effects of the magnetic field intensity on microstructure and crystallographic orientation of proeutectoid ferrite in Fe-0.36C alloy have been investigated. Results show that the amount of the Widmänstatten ferrite decreases with the increase of the magnetic field intensity. The transformed proeutectoid ferrite tends to elongate and align along the field direction due to the magnetic dipolar interaction. This tendency is more pronounced when the field intensity increases. Moreover, the enhancement of the <001> fiber component along the traverse field direction by magnetic field is obvious when the field intensity is stronger.

scholarly journals Self-magnetic field calculations in ray-tracing codes

2000 ◽  
Vol 18 (4) ◽  
pp. 601-610 ◽  
Author(s):  
STANLEY HUMPHRIES ◽  
JOHN PETILLO
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Ray Tracing ◽  
Field Calculation ◽  
Two Dimensional ◽  
Magnetic Forces ◽  
Iteration Cycle ◽  
Simple Rules ◽  
The Magnetic Field ◽  
Limited Accuracy

Beam-generated magnetic fields strongly influence the behavior of relativistic electron guns. Existing methods used in ray-tracing codes have limited accuracy and may not correctly represent nonlaminar beams. We describe a technique for the magnetic field calculation in a two-dimensional code based on the assignment of particle currents to the faces of elements in the mesh used for the electrostatic calculation. The balanced calculation of electric and magnetic forces in the same iteration cycle reduces the possibility of numerical filamentation instabilities. With simple rules of assignment on boundary faces, the method also handles field contributions of electrode currents. Several benchmark calculations performed on conformal meshes illustrate the versatility of the technique.

scholarly journals Two-dimensional hybrid model for magnetic field calculation in electrical machines: exact subdomain technique and magnetic equivalent circuit

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Brahim Ladghem Chikouche ◽  
Kamel Boughrara ◽  
Dubas Frédéric ◽  
Rachid Ibtiouen
Keyword(s):  
Magnetic Field ◽  
Maxwell’S Equations ◽  
Maxwell's Equations ◽  
Current Density Distribution ◽  
Electrical Machines ◽  
Field Calculation ◽  
Two Dimensional ◽  
Content Type ◽  
The Magnetic Field ◽  
Load Conditions

Purpose The purpose of this paper is to propose a two-dimensional (2-D) hybrid analytical model (HAM) in polar coordinates, combining a 2-D exact subdomain (SD) technique and magnetic equivalent circuit (MEC), for the magnetic field calculation in electrical machines at no-load and on-load conditions. Design/methodology/approach In this paper, the proposed technique is applied to dual-rotor permanent magnet (PM) synchronous machines. The magnetic field is computed by coupling an exact analytical model (AM), based on the formal resolution of Maxwell’s equations applied in subdomains, in regions at unitary relative permeability with a MEC, using a nodal-mesh formulation (i.e. Kirchhoff's current law), in ferromagnetic regions. The AM and MEC are connected in both directions (i.e. r- and theta-edges) of the (non-)periodicity direction (i.e. in the interface between teeth regions and all its adjacent regions as slots and/or air-gap). To provide accurate solutions, the current density distribution in slot regions is modeled by using Maxwell’s equations instead to MEC and characterized by an equivalent magnetomotive force (MMF) located in the slots, teeth and yoke. Findings It is found that whatever the iron core relative permeability, the developed HAM gives accurate results for both no-load and on-load conditions. Finite element analysis demonstrates the excellent results of the developed technique. Originality/value The main objective of this paper is to achieve a direct coupling between the AM and MEC in both directions (i.e. r- and theta-edges). The current density distribution is modeled by using Maxwell’s equations instead to MEC and characterized by an MMF.

scholarly journals The resistance of superconducting cylinders in a transverse magnetic field

1938 ◽  
Vol 166 (924) ◽  
pp. 43-55 ◽  
Keyword(s):  
Magnetic Field ◽  
Field Strength ◽  
Electrical Resistance ◽  
Applied Field ◽  
Transverse Field ◽  
Transverse Magnetic ◽  
Superconducting Cylinder ◽  
A Value ◽  
The Magnetic Field ◽  
Field Penetration

Experiments on the penetration of a magnetic field (de Haas and Casimir-Jonker 1934) into superconductors have shown that, when a superconducting cylinder is placed in an increasing transverse field, penetration of the field first occurs when the applied field strength reaches a value 0·50 H k , where H k is the critical field corresponding to the temperature of the experiment. Since, for this value of the applied field, the field strength, at the surface of the cylinder (von Laue 1932) where it is intersected by a diametral plane perpendicular to the direction of the field, will be precisely H k , the above result is in accordance with expectation. On the other hand, it was found by de Haas, Voogd and Jonker (1934) that under the same conditions the cylinder first exhibited electrical resistance when the applied field strength reached the value 0·58 H k . Since this discrepancy probably results from the properties of the “intermediate state” (Peierls 1936; London 1936; Landau 1937) occurring when the magnetic field just begins to penetrate the superconductor, it seemed desirable to investigate the matter in more detail.

ENTANGLEMENT MODULATION IN A SPIN CHAIN BY A LOCAL IMPURITY

2008 ◽  
Vol 06 (supp01) ◽  
pp. 567-573 ◽  
Author(s):  
TONY J. G. APOLLARO ◽  
ALESSANDRO CUCCOLI ◽  
ANDREA FUBINI ◽  
FRANCESCO PLASTINA ◽  
PAOLA VERRUCCHI
Keyword(s):  
Magnetic Field ◽  
Ground State ◽  
Spin Chain ◽  
Nearest Neighbor ◽  
Magnetic Impurity ◽  
Transverse Field ◽  
Transverse Magnetic ◽  
Spatial Modulation ◽  
Spin Pairs ◽  
The Magnetic Field

We study the ground-state entanglement properties of an XX spin 1/2 chain in transverse field, in its quasi-long-ranged ordered phase, with a magnetic impurity, represented in terms of an additional transverse magnetic field located at one precise site. For such a system, we show that a control of the ground state entanglement can be achieved by acting on the impurity field. To demonstrate this possibility, we evaluate exactly the nearest neighbor and next-nearest neighbor concurrence in the presence of the impurity. It turns out that either an enhancement or a quenching of entanglement between selected spin pairs can be obtained by acting on the intensity of the impurity. For specific values of the magnetic field a spatial modulation of concurrence along the chain is also obtained.

Characteristics of Recrystallization Texture Evolution in High Magnetic Field for Interstitial Free (IF) Steel Sheet

2005 ◽  
Vol 495-497 ◽  
pp. 465-470 ◽  
Author(s):  
Chang Shu He ◽  
Yu Dong Zhang ◽  
X. Zhao ◽  
Liang Zuo ◽  
Claude Esling
Keyword(s):  
Magnetic Field ◽  
High Magnetic Field ◽  
Recrystallization Texture ◽  
Steel Sheet ◽  
Texture Evolution ◽  
Interstitial Free ◽  
If Steel ◽  
Direction Parallel ◽  
The Magnetic Field ◽  
If Steel Sheet

High magnetic field is applied with the field direction parallel to the rolling direction during annealing of a cold rolled IF steel sheet. Results of X-ray ODF analysis show that, magnetic field annealing retards the normal recrystallization texture evolution for the IF steel sheet. It is worth noting that an abnormal increase of orientation intensity at {100}<110> is found after magnetic annealing for 25min at 650°C. When the magnetic field strength is increased from 10 Tesla to 14 Tesla, the a-fiber is further strengthened, especially the {100}<110> component. Combined with EBSD analysis results, it is considered that the magnetic field does not change the mechanism of recrystallization texture evolution for the IF steel sheet in the present case.

scholarly journals Magnetic Field Saturation of Non-Insulation High-Temperature Superconducting Coils during Overcurrent

Electronics ◽  
2021 ◽  
Vol 10 (22) ◽  
pp. 2789
Author(s):  
Wei Wu ◽  
Yusong Gao ◽  
Zhijian Jin
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Hot Spot ◽  
Axial Direction ◽  
Load Factor ◽  
Field Calculation ◽  
High Temperature Superconducting ◽  
Superconducting Coils ◽  
The Magnetic Field ◽  
Double Pancake

Non-insulation high-temperature superconducting coils provide a much lower risk of burnout in fault/abnormal conditions, such as hot-spot quench and overcurrent. This study employs an equivalent circuit grid model, coupled with magnetic field calculation and the E–J power law of superconductors, to deeply and systematically investigate the overcurrent charging process in a double-pancake non-insulation coil. An evident saturation of the magnetic field in the axial direction of the coil was observed and verified by experiments. Experimentally, the entire process, including the behavior of the magnetic field, was consistent with the numerical results. Based on the verified model, two main points were addressed: (1) Transient current distribution inside the coil during overcurrent charging was studied. Potential quenching risks were found to be at the innermost and outermost turn near the electrodes, as well as the pancake-to-pancake connection part. (2) Magnetic field saturation, which is a unique phenomenon in non-insulation superconducting coils during overcurrent charging, was studied in detail and first quantitatively defined by a new concept “converged load factor”. Its relationship with turn-to-turn resistivity was revealed.

Numerical Analysis of Electromagnetic Field of Solid Rotor Asynchronous Permanent Magnetic Coupling by Finite Element Method

2008 ◽  
Vol 575-578 ◽  
pp. 1376-1381 ◽  
Author(s):  
Chao Jun Yang ◽  
Quan Wen Li ◽  
Hong Liang Ma ◽  
Sheng Fa Jiang
Keyword(s):  
Magnetic Field ◽  
Finite Element Method ◽  
Electromagnetic Induction ◽  
Permanent Magnets ◽  
Magnetic Coupling ◽  
Analytic Method ◽  
Field Calculation ◽  
New Type ◽  
Transmission Capability ◽  
The Magnetic Field

A new-type of solid rotor asynchronous magnetic coupling which works on the principle of electromagnetic induction is researched by ourselves. This kind of asynchronous magnetic coupling can solve the problem effectively that the permanent magnets on its inner rotor is demagnetized if its temperature is too high, because its inner rotor need not the permanent magnets. in order to study the transmission capability of the new-type magnetic coupling, its magnetic field should be analyzed. Because of its magnetic field variety, it is extremely complicated and a precision result is difficult to be got by the analytic method of the magnetic field calculation. Here the software ANSYS FEM is used to analyze its magnetic field. And some formulas were deduced and used to calculate its torque. The experimental and calculational results indicate that this design is practicable.

Sign in / Sign up

Export Citation Format

Share Document