| Research Abstract |
In the processes of I. Solidification, II. Electro deposition, III. Vapor deposition and IV. Solid reaction, the mechanism of crystal and structure alignments in precipitated, deposited and reacted materials have been studied and the principle of controlling orientations of crystals has been investigated. The following results have been obtained.
I. Solidification
In a directional solidification of Fe-Cu alloy, it is found that the imposition of a high magnetic field makes Cu phase of a spherical shape precipitate in a crystal grain not a grain boundary.
II. Electrode position
The electro deposition in a ZnCl-NiCl bath was conducted under the imposition of a high magnetic field. It is found that the deposited materials change Ni_<15>Zn_<21>-NiZn_5-NiZn with increase of magnetic field intensity.
III. Vapor deposition
Zn and Bi were vapor deposited on glasses under a high magnetic field. When the magnetic field was in perpendicular to a substrate plane, deposited materials were aligned to take a lower magnetization energy state. That is, Bi aligns in a-and b-plane and Zn does in c-plane.
IV. Solid Reaction
It is found that in the thermal treatment of coal-tar pitch a high magnetic field promotes to produce mesophase spherules and increase diameters of the spherules, and this mechanism bases on the magnetic orientation of a carbon hexagonal ring. By imposition of a high magnetic field on the carbonization process of PAN fibers, the strength of the carbon fibers obtained from the PAN fibers was increased in two times of the fibers without magnetic imposition.
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