Depinning field of domain walls with a misaligned grain boundary in iron-based soft magnets

ABSTRACTWe have been able to deduce a temperature dependence of the built-in potential in La2/3Sr1/3MnO3 grain boundary junctions. This has been performed by trimming a single grain boundary down to 1μm width with a focused ion-beam. We can thereby see the impact of single domain walls on the magnetoresistance and the current-voltage characteristics. We have also demonstrated the effect of averaging as we increased the number of junctions.

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Comparison of PZT ceramics based on the frequency dependence of conductance and a grain boundary - domain walls model

Ferroelectrics ◽

10.1080/00150199208223363 ◽

1992 ◽

Vol 127 (1) ◽

pp. 155-160 ◽

Cited By ~ 1

Author(s):

Roland Briot ◽

Paul Gonnard ◽

Michel Troccaz

Keyword(s):

Grain Boundary ◽

Frequency Dependence ◽

Domain Walls ◽

Pzt Ceramics

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Domain Structure and Properties of Soft Magnetic Iron- Based Alloys with Different Magnetic Treatment

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.168-169.219 ◽

2010 ◽

Vol 168-169 ◽

pp. 219-222

Author(s):

Yu.N. Dragoshanskii ◽

V.V. Shulika ◽

A.P. Potapov ◽

V.F. Tiunov

Keyword(s):

Magnetic Field ◽

Domain Structure ◽

Magnetic Loss ◽

Structure And Properties ◽

Soft Magnetic ◽

Soft Magnets ◽

Frequency Magnetic Field ◽

Electromagnetic Characteristics ◽

Iron Based ◽

The Impact

The paper deals with the domain structure and electromagnetic characteristics of soft magnetic iron-based alloys, which are formed by the impact of thermomagnetic treatment (TMT) - cooling of the material in the presence of a magnetic field. The effect of reducing the specific magnetic loss in materials, using a constant or alternating (different frequency) magnetic field is determined. It is shown that the minimum magnetic losses in the materials are obtained after TMT in an alternating magnetic field at high (~ 80 kHz) frequencies. This shows up the perspectives of TMT of soft magnets.

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Entropy-Driven Grain Boundary Segregation: Prediction of the Phenomenon

Metals ◽

10.3390/met11081331 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1331

Author(s):

Pavel Lejček ◽

Siegfried Hofmann

Keyword(s):

Grain Boundary ◽

Boundary Segregation ◽

Indirect Evidence ◽

Solute Segregation ◽

Grain Boundary Segregation ◽

Segregation Energy ◽

Iron Based ◽

Positive Segregation

The question is formulated as to whether entropy-driven grain boundary segregation can exist. Such a phenomenon would be based on the assumption that a solute can segregate at the grain boundary sites that exhibit positive segregation energy (enthalpy) if the product of segregation entropy and temperature is larger than this energy (enthalpy). The possibility of entropy-driven grain boundary segregation is discussed for several model examples in iron-based systems, which can serve as indirect evidence of the phenomenon. It is shown that entropy-driven grain boundary segregation would be a further step beyond the recently proposed entropy-dominated grain boundary segregation as it represents solute segregation at “anti-segregation” sites.

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Magnetic Properties of Rapidly Quenched Ribbons of Soft Magnetic Iron-Based Alloys after Annealing in Air and in Vacuum

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.233-234.255 ◽

2015 ◽

Vol 233-234 ◽

pp. 255-258

Author(s):

Nadezhda A. Skulkina ◽

Oleg A. Ivanov ◽

Elena A. Stepanova ◽

Irina O. Pavlova

Keyword(s):

Heat Treatment ◽

Magnetic Properties ◽

Domain Walls ◽

Uniaxial Tensile ◽

Soft Magnetic ◽

The Status ◽

Specific Magnetic Losses ◽

Uniaxial Tensile Stress ◽

Iron Based ◽

Physical Reasons

The physical reasons of influence of heat treatment in vacuum and air on magnetic properties of ribbon’s of amorphous soft magnetic iron-based alloys were investigated. It is shown that the heat treatment in the air contributes to retrieve the status of a material with lower specific magnetic losses. The reason for this is the formation during annealing of increased concentration along the axis of the ribbon of embedded in the surface atoms of hydrogen and oxygen. In this direction induced pseudo-uniaxial tensile stress, contributing to the reduction of the period of the domain structure and the speed of domain walls motion in the process of magnetization reversal.

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Formation and Growth of Antiphase Domains During Recrystallization of Cold-Rolled Cu3Au

MRS Proceedings ◽

10.1557/proc-364-41 ◽

1994 ◽

Vol 364 ◽

Cited By ~ 2

Author(s):

Rui Yang ◽

Robert W. Cahn

Keyword(s):

Grain Boundary ◽

Driving Force ◽

Domain Walls ◽

Early Stage ◽

Domain Size ◽

Boundary Motion ◽

Domain Formation ◽

Cold Rolled ◽

Antiphase Domains ◽

Grain Boundary Motion

AbstractAn experimental study by TEM was made of the morphology of the antiphase domains formed when heavily rolled Q13AU is annealed at a temperature slightly below the critical temperature for ordering, Tc. Domains are formed at the advancing grain boundary with extremely small size and grow as recrystallization proceeds. From an early stage, domain walls show a preference for (100) orientation. The key question is raised whether domain formation during recrystallization entails the presence of a disordered zone at a moving grain boundary near Tc, and the conclusion is that such a zone is probably present. A provisional theory is constructed for the genesis of domains during recrystallization, taking into account the dragging force which newly formed domains exert on a moving grain boundary thereby diminishing the effective driving force for grain boundary motion, and a critical domain size is estimated which should completely inhibit grain-boundary motion. The intriguing fact that no domains at all are formed during the recrystallization of strongly ordered intermetallics such as Ni3Al is briefly discussed and a reason is proposed.

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