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Al-Ni hypereutectic alloys with various compositions were solidified under various magnetic field conditions to investigate the alignment of primary Al3Ni phases. The results showed that the application of high magnetic fields could improve the homogeneity of the primary Al3Ni phase distribution and induce the alignment of primary Al3Ni phases in the direction perpendicular to the magnetic field direction to form chain-like structures. However, the alignment was different from the orientation of the Al3Ni phases. Furthermore, the degree of the alignment decreased with the increasing concentration of Ni element. This can be attributed to the combination effects of high magnetic field and alloy composition on the concentration field around the crystallized primary Al3Ni crystals. [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]

The effects of high magnetic field annealing on the inter-diffusion behavior of Co/Si (100) films were investigated using diffusion couple technique. Significant Co and Si inter-diffusion was verified by X-ray photoelectron spectroscopy. The inter-diffusion coefficients of thin-film/semiconductor were calculated. Compared to the no-field case, the inter-diffusion coefficients clearly increased when a high magnetic field of 11.5 T was applied at 300 °C, 350 °C, 450 °C and 500 °C. This effect can be attributed to an increase in the chemical potential gradient induced by magnetic free energy in a high magnetic field. For the samples at 400 °C, the inter-diffusion coefficients decreased when a high magnetic field of 11.5 T was applied. The phenomenon may due to the structure transformation caused by a high magnetic field. [ABSTRACT FROM AUTHOR]

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: 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: 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]

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]