Aperfeiçoando as Propriedades de Imãs Permanentes de SmCo5

Abstract

Sm-Co thin films, with nominal stoichiometry SmCo5, where deposited, by sputtering, on Si substrate (1 0 0) with different buffer layers (Cu, Cr and Ta). The microstructure and the magnetic properties were investigated. The coercivity values of Sm-Co films, with Cr and Cu buffers were similar to the HC previously reported in the literature (about 1 T). However, in films deposited on Ta buffer, the coercivity exceeded 4 T. Deposition of Sm-Co, at room temperature on Ta layers with different thickness, followed by different thermal treatments (TT) were made. The X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and magnetic analysis show a SmCo7 phase in films with TT at temperatures greater than 550oC, and Ta thickness greater than 30 nm. The Ta diffusion in SmCo7 structure seems to be the responsible to the hard magnetic properties of these films.