Project/Area Number |
13555190
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 展開研究 |
Research Field |
Structural/Functional materials
|
Research Institution | Akita Prefectural University |
Principal Investigator |
MAKINO Akihiro Akita Prefectural University, Faculty Systems Science and Technology, Professor, システム科学技術学部, 教授 (30315642)
|
Co-Investigator(Kenkyū-buntansha) |
BITOH Teruo Akita Prefectural University, Instructor, 助手 (40315643)
小島 章伸 アルプス電気(株), 磁気応用事業部・材料研究部, 主任技師(研究職)
|
Project Period (FY) |
2001 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥9,000,000 (Direct Cost: ¥9,000,000)
Fiscal Year 2003: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2002: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2001: ¥6,400,000 (Direct Cost: ¥6,400,000)
|
Keywords | nanocrystalline alloy / soft magnetic material / melt-spinning technique / high magnetic induction / high permeability / low core loss / ナノ結晶軟磁性合金 |
Research Abstract |
The nanocrystalline soft magnetic Fe-Nb-B based alloys, which can be produced by melt-spinning in air, with high saturation magnetic induction (B_s) as well as good soft magnetic properties have been developed. The Fe_<84>Nb_7B_9 alloy, which is the typical composition of the ternary Fe-Nb-B alloys, produced in air was extremely oxidized and showed brittleness. The ductile ribbons with the metallic luster were obtained for the ternary alloys with 6 at% Nb or less. Furthermore, higher B_s than 1.6 T has been obtained for the alloys with 6 at% Nb or less. However, the alloys exhibit inferior soft magnetic properties because the alloys have a mixed as-quenched structure composed of an amorphous phase and coarse α-Fe grains. These grains remain in the nanostructure after the crystallization and deteriorate the soft magnetic properties. The effect of the addition of some elements to Fe-Nb-B alloys on the as-quenched structure and the soft magnetic properties in the nanocrystallized state has been investigated. The simultaneous replacement of B by 1 at% P and Fe by 0.1 at% Cu in the alloy decreases the α-Fe grain size to the nano-scale in an as-quenched state and leads to a homogeneous nanostructure with good soft magnetic properties after crystallization. Analysis based on the random anisotropy model shows that a homogeneous nanostructure with small volume fraction of an inter-granular amorphous phase which has high Curie temperature is necessary for realizing the good soft magnetic properties. The Fe_<84.9>Nb_6B_8P_1Cu_<0.1> alloy exhibits high permeability of 41,000 at 1 kHz, very low core loss of 0.11 W/kg at 1.4 T and 50 Hz as well as higher B_S of about 1.61 T than that of the Fe_<84>Nb_7B_9 alloy.
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