Abstract
A ferromagnetic decagonal phase with high coercive forces exceeding 80kA/m (1 kOe) was found to form in rapidly solidified Mn45-x,Al25Ge15B15Fex (x=10 and 15 at%) alloys. The decagonal alloy containing 15 at%Fe consists of fine grains with sizes of 5 to 20 nm and has the periodic lattice spacing of 1.2 nm along the c-axis direction. Furthermore, the decagonal phase contains a high density of internal defects and the electron diffraction patterns consist of reflection spots with significant streaks along the < 100000) direction in the quasilattice a-b plane. The decagonal Mn30Al25Ge15B15Fe15 alloy exhibits ferromagnetic properties of 2.89 × 10-5 Wb m/kg for magnetization under a field of 1432 kA/m (J1432), 1.38 × 10-5 Wb m/kg for remanence (Br), 114 kA/m for intrinsic coercive force (1Hc), 1.4kJ/m3 for maximum energy product (B//)mas and 620 K for Curie temperature (7;). The high coercive force is presumably due to the formation of the nanoscale ferromagnetic decagonal grains containing a high density of phason defects. The first success of synthesizing the ferromagnetic decagonal alloy with the hard magnetic characteristics is encouraging for future progress of quasicrystalline alloys as a new type of engineering material.
Original language | English |
---|---|
Pages (from-to) | 559-563 |
Number of pages | 5 |
Journal | Materials Transactions, JIM |
Volume | 37 |
Issue number | 4 |
DOIs | |
Publication status | Published - 1996 |
Keywords
- Decagonal phase
- Ferromagnetic quasicrystal
- Hard magnetic property
- Large coercive force
- Manganese base alloy
- Nanoscale decagonal grain
- Rapid solidification
ASJC Scopus subject areas
- Engineering(all)