2018 - Sustainable Industrial Processing Summit & Exhibition
4-7 November 2018, Rio Othon Palace, Rio De Janeiro, Brazil
| Improved Nanocrystalline Structures for Magnetic Recording Marcos De Campos1; Jose Adilson De Castro1; 1UFF - FEDERAL FLUMINENSE UNIVERSITY, Volta Redonda, Brazil; PAPER: 336/Composite/Regular (Oral) SCHEDULED: 11:45/Mon./Grego (50/3rd) ABSTRACT: This paper will discuss in detail the adequate microstructural structures for magnetic recording. The maximum coercivity is obtained for single domain size particles [1], also known as Stoner-Wohlfarth particles. It was found that the squareness of hysteresis is improved with texture optimization, which is relevant as good squareness of hysteresis is an important issue for the magnetic recording industry. Detailed overviews on the texture effects of Stoner-Wohlfarth particles, as well as the effects of particle interaction, are given and discussed in detail. Additionally, modifications of the Stoner-Wohlfarth model, and the Callen-Liu-Cullen [2] model are analyzed. The spring effect observed in hysteresis curves of isotropic nanocrystalline materials can be explained with the Stoner-Wohlfarth model. Theories for magnetostic coupling between particles are also reviewed. References: [1] S.A. Romero, M.F. de Campos, A.J. Moreira, F.J.G. Landgraf, The Effect of the Cu and Sm content on the anisotropy field of Sm(CoFeCuZr)z isotropic nanocrystalline alloys. In: H. Fukunaga, S. Sugimoto (Eds.), Proceedings of the 22th International Workshop on Rare- Earth Permanent Magnets and Their Applications, Nagasaki, Japan, 2012, pp. 44-47. [2] E. Callen, Y.J. Liu and J.R. Cullen. Initial magnetization, remanence, and coercivity of the random anisotropy amorphous ferromagnet. Physical Review B Vol. 16 (1977), p. 263 |
