Soft magnetic properties of crystalline high Bs Fe-Co-Si and Fe-Co-Si-Al sputtered films

Soft magnetic properties of crystalline Fe-Co-Si and Fe-Co-Si-Al sputtered films have been investigated. Fe-Co-Si alloy films show high saturation flux density up to 14 kG with low coercivity of 0.7 Oe around the narrow composition range of Co 11 to 13 at.% and Si 20 to 22 at.%. In Fe-Si-Al the composition with soft magnetism was restricted around the Sendust composition. Fe-Co-Si-Al films which are solid solution of Fe-Co-Si and Fe-Si-Al show high saturation flux density of 12 to 14 kG with low coercive force of about 0.5 Oe. The soft magnetic characteristics in Fe-Co-Si-Al alloy films were comparable to Sendust film. These results suggest the existence of a composition region which possesses both zero-magnetostriction and zero-magnetocrystalline anisotropy constant in Fe-Co-Si and Fe-Co-Si-Al alloy films.