| Title |
Ordering behavior of Nanocrystalline FeAl |
| Authors |
최근섭(Keun Seob Choi) ; 김도경(Do Hyang Kim) ; 홍경태(Kyung Tae Hong) |
| Abstract |
Formation and disorder-order transformation of nanocrystalline FeAl have been investigated by a combination of scanning/transmission electron microscopy, X-ray diffraction analysis, differential scanning calorimetry and saturated magnetization measurement. Fe-50at% Al powders mechanically alloyed for 90 hours consist of 5-10㎚ size grains with a disordered b.c.c. structure. Lattice parameter of FeAl increases with mechanical alloying time not only due to solutionizing of Al into Fe, but also due to increasing of internal defects. X-ray diffraction, TEM analysis and magnetization values of nanocrystalline FeAl show that disorder-order transformation occurs at the temperature range of 300℃-320℃. Such a low-temperature ordering behavior is attributable to the ㎚-scale structure with a large amount of defects accumulated during mechanical alloying process. Present study shows that saturated magenization value is a good indicator of the ordering process. |