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The shift of the Kirkendall marker at the interface of Cu–Ni diffusion couples was examined under the influence of high magnetic fields up to 12 T. The shift distance of the marker increased remarkably with increasing magnetic flux density (B) in the case of the direction of diffusion parallel to B. However, if the direction of the magnetic field was perpendicular to that of diffusion, there was a negligible effect of the magnetic field on diffusion behavior. A calculation of intrinsic diffusivities of both components showed that the interdiffusion rates (∥B) are increased by high magnetic fields. These effects can be attributed to an increase in the chemical potential gradient induced by magnetic free energy in a high magnetic field. [ABSTRACT FROM AUTHOR]

The influence of high magnetic field annealing on the morphology, microstructure, and properties of pulsed-electrodeposited Co-Ni-P films was investigated. The as-deposited film with a rough surface changed into uniform nanocrystalline during the magnetic field annealing process. In particular, the formation of intestine-like appearance with spherical clusters vanishing is favored from a moderate magnetic field strength of 6 T, due to the polarized effects. Meantime, the diffraction peak (111) of α (fcc) phase shifts to the right direction, which is attributed to the fact that more Co atoms from phosphide phase are incorporated into the Ni lattice, in comparison with the case of annealing under 0 T and 12 T magnetic fields. The mechanical and magnetic properties of the films reach relative optimum values at B=6 T. The evolution of magneto-induced modification in the Co-Ni-P morphology, structure, and properties can be explained by the polarized effect and the diffusion-acceleration effect under a high magnetic field. [ABSTRACT FROM AUTHOR]

Several samples of Zn-Sb alloys, composed with β-ZnSb and Zn phases, were prepared by solidification under high magnetic fields (HMFs). The microstructure evolution and thermoelectric (TE) properties of the alloys were then investigated. Zn phase precipitated as strip and presented reticulation structure in the samples without HMFs. When the HMFs were imposed, Zn became disperse and the strip of Zn became thinner and shorter. In addition, the c-axis of Zn crystals showed a tendency to orientate toward the direction perpendicular to the magnetic field direction. The samples prepared under HMFs had higher resistivity and Seebeck coefficient and lower thermal conductivity. When compared to the solidified samples without HMFs, the application of 8.8 T of HMF increased the maximum figure of merit 3.7 times. In addition, the relationship between microstructure and TE properties was also analyzed. [ABSTRACT FROM AUTHOR]

This paper studies the effects of a high magnetic field on the structural evolution and magnetic properties of nanocrystalline films prepared on quartz substrates by a molecular beam vapor deposition (MBVD) method. Atomic force microscope, X-ray diffractometer, transmission electron microscope and vibrating sample magnetometer were used to study the microstructures and magnetic properties of the films. The results indicate that high magnetic field has no obvious influence on crystal structures except changing the lattice constant of the films. However, the high magnetic field can refine particle size. The film deposited under magnetic field tends to grow through columnar mode because of the magnetized particles aligning along the direction of magnetic field. Furthermore, the ordered and dense arrangement of atoms results in more spins contained in per unit volume and improves the saturation magnetization (Ms). Ms of the 6 T film increases by 70% (578 emu/cm3) than that of the film without magnetic field (341 emu/cm3), and the coercivity is also slightly increased for the 6 T film. Nanocrystalline magnetic Ni films were prepared under high magnetic field. It is found that a high magnetic field changes the growth mode and increases the saturation magnetization of Ni film. The high magnetic field also improves the ordered and dense arrangement of Ni atoms. [ABSTRACT FROM AUTHOR]

The influence of static magnetic field of 4 T on electroless Ni-P deposition process and post-annealing was investigated in this study. The results from differential scanning calorimeter have shown that the imposed high magnetic field during electroless deposition had a further beneficial effect on defects migration and annihilation after Ni-P alloys heated at around 250 °C. Furthermore, it is found that some metastable phases were presented after magnetic annealing at 300 °C (below crystallization temperature), and the hardness of magnetic-annealed Ni-P alloys was greater than that of conventionally annealed Ni-P alloys. The morphology of the Ni-P alloys was characterized by scanning electron microscope, and shows typical spherical nodular structure for the as-deposited Ni-P alloys. The boundaries of these spherical nodular crystals blurred after annealing; however, the boundaries were apparently observed after magnetic annealing at 300 °C. [ABSTRACT FROM AUTHOR]

The effects of an 11.5 T high magnetic field on the growth behavior of compounds layers during reactive diffusion in solid Al/solid Mg diffusion couples have been investigated. After annealing with and without a magnetic field, the interfacial zone was still composed of two layers of stable compounds β (MgAl) and γ (MgAl), but the thicknesses of the layers were increased by the magnetic field. Data analysis of the thicknesses of compound layers showed that the growth of the γ layer was controlled by grain boundary diffusion as well as volume diffusion at B=0 T, but only controlled by volume diffusion when an 11.5 T high magnetic field was applied. The interdiffusion coefficients for the samples annealed at 643-693 K were calculated from the parabolic relationship between the migration of the interface and the annealing time. The results show that the diffusion constant increased due to the high magnetic field, increasing the chemical potential gradient, and in turn it caused the interdiffusion coefficient to increase. [ABSTRACT FROM AUTHOR]

The kinetics of the reactive diffusion at the liquid Al/solid Cu interface was investigated at T = 973 K, 1023 K, and 1073 K in a high magnetic field of 11.5 T. During the annealing process, three stable compounds (δ, ξ2, and η2) layers were formed at the interface of the couples, and a power function relationship between the mean thickness of the diffusion layers and the annealing time kept stable. Without magnetic field, the exponent of the power function for each compound layer was higher than 0.5, but it was close to or even smaller than 0.5 with a magnetic field. Compared with the field-free environment, the migration of the liquid/solid interface due to interdiffusion decreased in the presence of a magnetic field. A considerable decrease in the effective diffusion coefficient under a magnetic field provided a likely explanation for the experimental results. [ABSTRACT FROM AUTHOR]

The size segregation of sintering materials in a chute flow is utilized to prepare well-bedded feedstock for sintering quality improving, and magnets are installed below the chute to enhance size segregation. By the braking role of magnetic force, the particles of different sizes which poured down to sloping chute are separated:the coarse particles drop to the far-side of the sloping chute and the fine particles drop near the sloping chute. As the sintering pallet is continuously moving, the coarse particles are distributed into the lower portions and the fine particles are aggregated on the top of the layer..By using the non-contacting magnetic force,the technique of magnetic segregation feeding overcomes a series of defects such as adhering and wearing in the existing segregation feeding devices. and the device is characterized by simple structure, easy operation, no need of energy,and safety, etc. Discrete element method (DEM) simulations are carried out to explore the optimal arrangement of the magnets.The simulations show that proper magnetic field can significantly enhance the segregation,and the simulation results are in good agreement with the experiments and industrial systems designed with consultation to the results.Depend on those,the technique of magnetic segregation feeding have been developed and applied in the three sintering line of Baoshan Iron & Steel Co., Ltd..The results of industrial application show that the distributions of particles, carbon and FeO in sintering layer have been remarkably improved. In guaranteeing to the quality of sintering ore materials, the productivity of sintering strand raised 2.1% and the fuel ratio decreased 1.7%. [ABSTRACT FROM AUTHOR]

The effect of a magnetic force on creating an aligned two-phase microstructure in a Fe-0.25wt%C alloy under magnetic field gradients has been investigated. Through the changes in the heating temperature, both dipolar interactions and magnetic forces work together during the austenite to ferrite transformation. The results showed that the aligned two-phase microstructure is not observed under the influence of the magnetic force alone. The ferrite grains are elongated due to dipole interactions at the early stages of their nucleation and growth and then the magnetic force turns the elongated ferrite grains, whose major axis is not parallel to the direction of magnetic force, to the direction of the field in the presence of magnetic field gradients. [ABSTRACT FROM AUTHOR]

Mn-90.4wt% Sb alloy specimens were solidified under both uniform magnetic field and magnetic field gradient conditions. The solidification behavior was examined to elucidate the effects of high magnetic fields on the solidified structure evolution of this hypoeutectic alloy. The macrostructures on the longitudinal section of the alloys were investigated by optical microscopy and x-ray diffraction (XRD). The volume fraction of primary MnSb phases and the interrod spacing of the eutectic were measured by metallographic analysis. It was found that the segregation of the primary MnSb particles at the certain regions of the specimens occurred under the influence of high magnetic field gradients. The MnSb phases obtained under magnetic fields were oriented with their (h0 l) planes along the direction of the magnetic field. Both the volume fraction of primary MnSb phases and the interrod spacing of the eutectic were decreased upon the application of the high magnetic fields. [ABSTRACT FROM AUTHOR]

An Mn–Sb alloy was isothermally annealed in a semisolid state without and with a high magnetic field. The effect of the high magnetic field on the evolution of the crystal orientation of ferromagnetic Mn–Sb particles during their coarsening process was investigated. The effect of the high magnetic field on the magnetic property of the treated alloys was studied. With the application of the high magnetic field, the Mn–Sb particles were orientated with their \boldsymbol c -axes perpendicular to the applied magnetic field. The orientation degree of the particles increased with increasing annealing time. The magnetic field-treated alloys showed a magnetically anisotropic behavior. A processing route for producing magnetic particle-reinforced compounds is proposed. [ABSTRACT FROM AUTHOR]

We investigated the effect of a high magnetic field on the magnetostriction of TbFe2-based alloy during a semi-solid state process. With the application of a high magnetic field, magnetostrictions under free and compressive prestress conditions remarkably increased. Obvious magnetically anisotropic behavior of the TbFe2-based alloy was observed. A high <111> orientation of TbFe2 phase along the magnetic-field direction was produced. The increase in magnetostriction and the magnetically anisotropic behavior were attributed to the <111> orientation of TbFe2 phase during the treatment in the semi-solid state induced by the magnetic field. [ABSTRACT FROM AUTHOR]

In this study we have explored how a high magnetic field (HMF) affects the structure and magnetic properties of Fe thin films fabricated on Si (100) substrates at various substrate temperatures by using a thermal evaporation method. At a substrate temperature of room temperature (RT), the HMF increased the width of column and the formation energy of the films. This behavior occurred because the HMF induced an excess energy-Zeeman energy which is larger than the sum of the kinetic energy and thermal energy of Fe without the HMF. This increased the particle size and decreased the roughness of the film deposited at RT and 6 T. When the substrate temperature was increased to 400 °C, the growth mode is changed from columnar (RT) to layered (400 °C). The HMF increased the grain size. The film deposited at RT and 6 T had much improved soft magnetic properties from its modified microstructure. While thermal disturbances decreased the effect of HMF on the magnetic properties of the film deposited at 400 °C. In particular, the influence of HMF on the microstructure and magnetic properties of Fe films is significant not in the evaporation stage but in the condensation process of film. [ABSTRACT FROM AUTHOR]

The influence of interdiffusion on the magnetic properties of Co/Si (100) films after thermal annealing in the presence of a strong magnetic field was investigated. The interdiffusion coefficients of films that were annealed at temperatures of 380 °C and 420 °C in the presence of high magnetic fields were not affected. However, the interdiffusion coefficient of films annealed at 400 °C in the presence of a high magnetic field decreased significantly. The change in the interdiffusion coefficient, caused by high magnetic field annealing, increased the content of the magnetic phase. This increase in the magnetic phase improved the saturation magnetization. A new method of high magnetic field annealing is presented that can modulate the diffusion and magnetic properties of thin films. [ABSTRACT FROM AUTHOR]

The Fe 60 Ni 40 (in atomic %) nanoparticles (NPs) thin films with 90 nm thickness were prepared on 25 and 400 °C quartz substrates by using the molecular beam vapor deposition (MBVD) method under a 6 T high magnetic field (HMF). The effects of a HMF on the structure evolution and properties of Fe–Ni thin films were studied by using X-ray diffraction, atomic force microscopy, transmission electron microscopy, vibrating sample magnetometer and four-point probe method. The results show that the crystallinity of thin films is enhanced by a 6 T HMF, and a 6 T HMF changes phase composition of thin films on 25 °C substrate. It is found that the nanoparticle size decreases; the nanoparticle size distribution becomes narrow, and the root mean square (rms) roughness of thin films decreases under a 6 T HMF relative to that without HMF. These lead to the decrease of coercive force, and the increase of in-plane remanence ratio under a 6 T HMF. [ABSTRACT FROM AUTHOR]

Abstract: The effect of a high magnetic field on phase formation and determination in Ni–Fe film at nanoscale is reported. The bcc structure of the film changed to the coexistence of bcc and fcc phases by increasing the substrate temperature from 25 to 200 to 400 °C without magnetic field. Under a 6 T magnetic field, a coexistence of bcc and fcc phases was formed whatever structures the films prepared without magnetic field are. Furthermore, each nanograin exhibited only a single phase. The effect of high magnetic field indicates that the reduction in the Gibbs free energy (entropy) for the fcc phase by the high magnetic field is larger than that for the bcc phase. Furthermore, the reduction is different for various substrate temperatures. The results indicate that the phase formation is tunable at the nanoscale under high magnetic field. [Copyright &y& Elsevier]

Abstract: We report on the influence of magnetic field strength on the alloy Tb0.27Dy0.73Fe1.95 during slow-cooling solidification. We examined the effect of magnetic field strength on microstructure, magnetization, and magnetostrictive properties of this giant magnetostrictive alloy. We found that after field-treated solidification, the microstructure of specimens had a distinct grain arrangement and displayed magnetic anisotropy. The crystal orientation changed from random in the field-free treatment to aligned along the 〈110〉 direction in flux densities of 1 and 2.2T, and along the easy magnetization axis 〈111〉 at a flux density of 4.4T. In consequence, the magnetostrictive coefficient of the samples under various stresses improved with increasing magnetic flux density. Both the d 33 and k 33 values and the energy transformation efficiency of the field-treated specimens showed strong enhancements. [Copyright &y& Elsevier]

Highlights: [•] We present the change of the crystal orientation and magnetostriction of TbFe2 based alloy during treatment in the semi-solid state in high magnetic fields. [•] Orientation of the TbFe2 phase undergoes a transformation of 〈113〉 to 〈111〉 to 〈110〉 with increasing magnetic flux density. [•] Magnetostrictive property is slightly lowered at 4.4T, but strongly enhanced at 8.8T and 11.5T. [ABSTRACT FROM AUTHOR]

Abstract: The effect of high magnetic fields up to 12T, applied during electrodeposition process, on the morphology of nanocrystalline CoNi films has been investigated. The magneto-induced dramatic modifications in the morphology were observed by using field-emission scanning electronic microscopy and atomic force microscopy. Along with the increase of magnetic flux density (B), the grain size and the surface roughness of the films increased to reach a maximum value at a field of 9T. Meanwhile, higher magnetic flux density could improve cobalt atomic percentage in the film due to the impacts of magnetohydrodynamic effect. However, at a high field of 12T, the paramagnetic force played a predominant role in a decrease of mass transport, resulting in minimum grain size and roughness, even smaller than that of the ordinarily (B=0T) sample. [Copyright &y& Elsevier]

Abstract: Isothermal heat treatment experiments of an Al–4.8mass%Cu alloy were carried out under different magnetic field intensities, at different temperatures and for different holding times. The influence of high magnetic fields on area fraction of θ phase in the solidified microstructure was investigated. It was found that the area fraction of the θ phase was lower when imposing the magnetic field compared to samples heat-treated without magnetic field. In other words, the magnetic field accelerated the phase transformation to the equilibrium state. In addition, the area fraction of the θ phase was independent of magnetic field intensity. This effect of high magnetic fields on the decreasing of the θ phase was discussed from the viewpoint of the effect of high magnetic fields on diffusion. [Copyright &y& Elsevier]

Abstract: Nanocrystalline Fe x Ni1−x (in at%, x=0.74, 0.6, 0.55, and 0.3) thin films were prepared on a 25°C quartz substrate by using a molecular beam vapor deposition method with and without a 6T magnetic field. The microstructure of the thin films was characterized by energy dispersive x-ray spectroscopy, x-ray diffractometry and transmission electron microscopy. The magnetic and electrical properties of the thin films were examined by a vibrating sample magnetometer and four-point probe method. Results show that the thicknesses of these films with different compositions are 50, 90, 80, and 150nm, correspondingly. The crystallinity of Fe x Ni1−x (x=0.74 and 0.6) thin films is enhanced, and the γ 〈111〉 orientation degree of the Fe x Ni1−x (x=0.55 and 0.3) thin films increases under a 6T magnetic field. The grain refinement and defect decrease under 6T magnetic field are affirmed by TEM. A 6T magnetic field can help the thin films transform from anisotropy to isotropy. The soft magnetic properties of the Fe x Ni1−x (x=0.74, 0.6, 0.55, and 0.3) thin films are enhanced, and their resistivities decrease under a 6T magnetic field. [Copyright &y& Elsevier]

Abstract: In this work, Mn–Sb alloys were melted and held in various magnetic field gradients for various times. The corresponding distributions of the alloying elements in the alloys in liquid state were revealed by a quenching method. It was found that the primary MnSb showed a relatively uniform distribution in the alloy quenched in the magnetic field gradient of B dB/dz=0T2/m, while it was mainly distributed in the lower and upper part of the alloys quenched in negative and positive magnetic field gradients, respectively. The experimental results show that it is possible to in situ control the distributions of alloying elements in alloys in the liquid state using high gradient magnetic fields if there is a difference in magnetic susceptibility. [Copyright &y& Elsevier]

Abstract: The effect of high magnetic fields on the nucleation behavior of Ni-90at%Cu alloys and pure Sb were investigated. It was found that the undercooling of both Ni-90at%Cu alloys and pure Sb before nucleation was increased by the application of a high magnetic field of 11.5T. An obvious grain refinement was observed in the Ni-90at%Cu alloys solidified in the high magnetic field. Such grain refinement could be linked to the increase of the undercooling. The increase in the undercooling in the high magnetic field was attributed to the suppressing effect of the Lorentz force on the convection in the melt. Such suppressing effect could delay the formation of oxides which were responsible for the heterogeneous nucleation of the materials. [Copyright &y& Elsevier]

Abstract: With the imposition of a high magnetic field up to 11.5T, the morphologic transition of the MnBi phase and the magnetic properties of the Bi–4.36wt.% and 8.25wt.% Mn alloy specimens solidified from a semi-solid state were investigated. Compared with the irregular shape and unequal dimensions of MnBi grains under 0T, the coarsened MnBi grains were connected together and tended to be parallel to the direction of the external field of 11.5T. The changes might be attributed to the Ostwald ripening of ferromagnetic grains in the isothermal holding stage and subsequent aggregation along the direction of external field driven by mutual magnetic force among the grains. The uniform orientation of the ferromagnetic MnBi grains obtained in the microstructures effectively improves the saturation magnetization of the Bi/MnBi composite materials, but the oversized grains and the defects in grains make the coercivity decrease. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic properties of Fe–49%Sn monotectic alloys were investigated after the alloys were solidified with and without a high magnetic field of 10T. The results showed that there was a significant difference between their hysteresis loops measured parallel and perpendicular to the applied high magnetic fields for the solidification process. Therefore, high magnetic fields applied in solidification process increased the magnetic anisotropy in the alloys. Along the parallel directions of the high magnetic field applied in their solidification process, the saturation magnetization M s, magnetic susceptibility dM/dH M and remanent magnetization of Fe–49%Sn monotectic alloys were increased obviously, which resulted from the improvement in the aligned microstructure of Fe–Sn alloys by applying the high magnetic field to the solidification process. A modified Stoner–Wohlfarth model was introduced to explain the experimental results. [Copyright &y& Elsevier]

Abstract: Mn–89.7wt.%Sb alloy specimens were solidified in various magnetic fields with different holding times. The influence of the high magnetic field on the orientation of both the primary and eutectic MnSb crystals and on the alignment of the primary MnSb grains in the alloys has been investigated. It was found that the primary MnSb crystals were oriented with their c-plane parallel to the imposed magnetic field direction, but the eutectic MnSb from a eutectic MnSb alloy could not be oriented by the high magnetic field. The primary MnSb dendrites were aligned along the magnetic field direction. This alignment may be attributed to combined effects of crystal orientation, crystal growth feature and heat flow. [Copyright &y& Elsevier]

Abstract: The effects of high magnetic fields on the migration and rotation of TiAl3 particles in an Al–7wt.% Si alloy were studied. Without magnetic fields, the rod-like TiAl3 particles segregate at the lower part of the solidified structure. Under high uniform magnetic fields, these particles rotate to an orientation with their longitudinal axes parallel to the direction of the magnetic flux. The segregation of the particles reduces with the increase of the magnetic flux density. A negative gradient field enhances the effect of the uniform magnetic field. By altering high magnetic fields, Al–Si alloy samples containing homogeneously distributed and preferably aligned TiAl3 particles were prepared. [Copyright &y& Elsevier]

Abstract: The effects of high magnetic fields on the as-cast microstructure and grain boundaries of binary Al–Li alloy were investigated. It was found that secondary dendrite arm spacing (SDAS) decreased and the distribution of the SDAS became uniform under high magnetic fields. The application of a high magnetic field had no effect on the type of precipitated phases in the alloy, although δ′ (Al3Li) precipitates coarsened under the field of 11.5T. Area fraction of grain boundary (AFGB) slightly decreased at first and then increased with increasing magnetic flux density under uniform magnetic fields, while it decreased under magnetic field gradients. [Copyright &y& Elsevier]

MnSb/Sb–MnSb functionally graded material (FGM) has been successfully fabricated using a semi-solid forming process under magnetic field gradients. Mn–Sb alloy with a hypoeutectic composition was used to produce particle-dispersed composites. The graded composition of MnSb particles could be controlled by adjusting the BdB/dz value of the field gradient and the holding time. The direction along which the volume fraction of the particles increased could also be controlled artificially by adjusting the field gradient direction. [Copyright &y& Elsevier]

Bulk layered synthetic Mn–Sb composites, with a gradient structure in morphology and composition towards the surfaces, were fabricated directly in situ under high magnetic field gradient conditions. Both of the primary phases of Mn–Sb binary system, i.e. MnSb and Sb, were found to segregate simultaneously from desired domains with a gradient interface in morphology in those alloys with hypo-eutectic composition. The volume fraction of the segregated phases strongly depended on the product of the magnetic flux density and its gradient. [Copyright &y& Elsevier]

Abstract: The effects of magnetic field on nucleation barrier of the phase transformation from austenite to ferrite at different cooling rates in 42CrMo steel have been investigated. The microstructures of ferrite and pearlite aligned along the magnetic field direction (parallel to the hot-rolling direction) are obtained at a cooling rate of 10°C/min, resulting from the kinetic effects of the applied magnetic field during cooling and the microstructural influences of an inhomogeneous deformation occurring during the previous hot rolling. In this case, the formation of ferrite grains at higher temperatures is attributed mainly to the preferential nucleation at austenite boundaries. However, a fairly uniform microstructure of randomly distributed ferrite and pearlite is formed at a high cooling rate of 46°C/min in the magnetic field of 14T, as a result of both intergranular and intragranular nucleation at relatively low temperatures. Probing into this issue is helpful to gain a better understanding of kinetic influences of magnetic field on the phase transformation from austenite to ferrite. [Copyright &y& Elsevier]

Abstract: The effects of high magnetic field annealing on the interdiffusion of Co/Ni bilayer films were investigated in this paper. A clear CoNi alloying zone can be observed by field emission scanning electron microscopy and energy dispersive spectroscopy, for samples annealed with and without magnetic field. Significant Co and Ni interdiffusion was verified by X-ray photoelectron spectroscopy. Based on the thickness of the diffusion layer, the distribution of atoms and the microstructure of interfacial products, the interdiffusion coefficients of the bilayer diffusion couples were calculated. Compared with the no-field case, the interdiffusion coefficient clearly increased when a high magnetic field of 12T was applied. This effect can be attributed to an increase in the chemical potential gradient induced by magnetic free energy in a high magnetic field. [Copyright &y& Elsevier]

Abstract: The effects of an 11.5T magnetic field on phase equilibria of Mn–Sb system during solidification process were investigated with the aid of direct thermocouple measurements and quantitative metallography analysis. It was found that the magnetic field could increase the eutectic line and the area fraction of the MnSb in eutectics, and thus shift the eutectic point to the high Mn concentration side. It could also increase the Sb liquidus temperatures by a decreasing trend with an increasing Sb composition, but show little effect on the MnSb liquidus temperature. The above results could be related to the variation in the magnetic susceptibility during the phase transformation. [Copyright &y& Elsevier]

Abstract: The application of a high magnetic field during pack aluminization process induced a significant change in the final products at the surface of substrate Cu. Experimental studies demonstrated that the coatings consisted of two layers namely α + γ 2 and α with the magnetic flux density (B) ranging from 0 to 8.8 T, whereas only α layer with Kirkendall voids was observed in case of B ≥10 T. With B increasing, the total thickness of coating first increased to a maximum at a field of 6.6 T, and then decreased with further increasing magnetic flux density. These results may be attributed to the contradictory effects of high magnetic fields on chemical reaction and on diffusion. [Copyright &y& Elsevier]

Abstract: The effect of uniform and gradient high magnetic fields on the microstructures of Fe-0.25 mass%C steel was investigated by optical microscopy. The results show that aligned two-phase microstructure was formed when uniform magnetic fields are imposed during the austenite to ferrite transformation. Such aligned two-phase microstructure became more distinct when gradient magnetic fields are imposed. The pearlite colonies are small and the space between columns is reduced in the specimen treated under gradient magnetic fields compared with those in the specimen treated under a uniform magnetic field. The mechanism on effect of gradient magnetic field is discussed from the viewpoint of dipolar interaction and the effect of magnetic force on ferrite grains. [Copyright &y& Elsevier]