| Project/Area Number |
18560643
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Physical properties of metals
|
|---|
| Research Institution | Yokohama National University |
|---|
Principal Investigator |
TAKEDA Mahoto Yokohama National University, Dept. Eng., Prof. (30188198)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HIROI Zenji Univ. Tokyo, Inst. Soild State Physics, Prof. (30192719)
SONG Sungyu Kyushu Univ., HVEM lab., Research associate (50403994)
|
|---|
| Project Period (FY) |
2006 – 2007
|
| Project Status |
Completed (Fiscal Year 2007)
|
| Budget Amount *help |
¥3,650,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥150,000)
Fiscal Year 2007: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2006: ¥3,000,000 (Direct Cost: ¥3,000,000)
|
|---|
| Keywords | nano-scale magnetic particles / spontaneous formation / Lorentz Microscopy / SQUID measurement / 磁性微粒子 / 自己組織化過程 / TEM / 磁気特性 |
|---|
| Research Abstract |
The present study investigated the spontaneous formation of nano-scale cobalt and iron particles in copper matrices, using Lorentz microscopy, high-resolution TEM, EELS analysis and SQUID measurements.
1) Spherical iron, cobalt and iron-cobalt particles are formed at the initial stages of the precipitation. Although the spherical cobalt particles are transformed into cubic particles, iron particles have a less tendency to evolve in the shape, during the annealing.
2) Iron nano-particles also make a pair-wise couplings, but the couplings were more ambiguous than Co pairs. On the contrary, spherical iron-cobalt complex particles are arranged along <100> orientations of copper matrices.
3) The specimens receiving a short annealing shows a cusp at 40K, but they have another cusp around at 120K.
4) Lorentz microscopy shows that the magnetic moment of the particles are oriented to 100 of copper matrices. The magnitudes of the moments are increased with the sizes, but there seem a critical size switching from fcc to bcc in structure.
|
