Effective grain pinning revealed by nanoscale electron tomography
| Title | Effective grain pinning revealed by nanoscale electron tomography |
| Publication Type | Journal Article |
| Year of Publication | 2011 |
| Authors | Wu YQ, Tang W, Dennis KW, Oster N, McCallum RW, Anderson IE, Kramer MJ |
| Journal Title | Journal of Applied Physics |
| Volume | 109 |
| Pages | 07a705 |
| Date Published | 04/01 |
| Type of Article | Proceedings Paper |
| ISBN Number | 0021-8979 |
| Accession Number | ISI:000289949000223 |
| Keywords | ADDITIONS, magnetic-properties, melt-spun ribbons, microstructure |
| Abstract | The grain pinning behavior of TiC particles in a rapidly solidified MRE-Fe-B (MRE = Nd + Y + Dy) nanocrystalline hard magnet was studied using electron tomography (ET). The 3D reconstruction overcomes the inherent 2D nature of conventional transmission electron microscopy (TEM) to reveal how this grain boundary phase controls the nanoscale structure in the rapidly solidified alloy. The 3D reconstruction was performed on the optimally annealed alloy (750 degrees C/15 min) with hard magnetic properties of M-r = 8.1 kGs, H-c = 6.2 kOe, (BH)(max) = 11.2 MGOe measured at 300 k. The sampled volume, 425 x 425 x 92.5 nm(3), contains more than 20 grains of the RE2-14-1 phase and more than 70 TiC nanoparticles. The TiC grains' shapes depend on their sizes and locations along the grain boundary. Most of the TiC particles are oval or short rod like shapes and range from 5 nm to 10 nm. TiC particles less than 10 nm formed between adjacent 2-14-1 grains, while the largest ones formed at triple junctions. There are similar to 1.7 x 10(8) TiC particles within a 1 mm(3) volume in the alloy. This accounts for the strong grain boundary pinning effect, which limits grain growth during annealing. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3549603] |
| URL | <Go to ISI>://000289949000223 |
| DOI | 10.1063/1.3549603 |
| Alternate Journal | J. Appl. Phys. |
