Mlaostructuecontno llnighmlicf ; mfionand crystal gowthunderanagieticteld

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In this research project, we focused on microstructure evolution (regular structure, crystallographically aligned structure and so on) during solidification and coarsening.(1) Formation of the regular structure by the magnetic effect on the solidifying frotSuppression of the local melt flow (the micro-MHD effect) becomes apparent under a high magnetic field. For the Al-In monotectic alloys, the regular structure in which the rods are regularly aligned was formed. From viewpoints of the micro-MHD and the dipole-dipole interaction, the formation of the regular structure was discussed.(2) Formation of the regular structure by the dipole -dipole interaction in fluidThe dipole-dipole interaction enhanced the regularity of the Ti02 spherical particles with a diameter from sub micro meter to several micrometer after the sedimentation. The results showed that the magnetic effect could be used for fabricating crystals which consisted of the fine particles (oxide particles).(3) Formation of the aligned structure during solid state transformationThe phase filed model that includes the principles of the thermodynamics was introduced to analyze the formation of the crystallographically aligned structure during coarsening process. The calculation showed that the magnetocrystalline anisotropy energy could contribute to the formation of the aligned structure in some conditions. Inhomogeneity in grain size and distance between grains degraded the degree of the alignment.In addition, the three dimensionally aligned structure was fabricated for the intermetallic compound with the lower crystal symmetry.