Formation and Magnetic Properties of Fe-6.5% Si-Oxides Composite Powders by Mechanical Alloying

Abstract

Fe-Si-ZrO₂ composite powders were prepared by mechanical alloying using vibrating ball mill under Ar atmosphere. The magnetic properties and thermal stability for Fe-Si-ZrO₂ composite powders were investigated by mesns of VSM, DSC and X-ray diffraction. The addition of Si increased the coercivities, He for Fe-ZrO₂ composite powders as much as 130-150% of those for the powders without Si against expectation. On the other hand, X-ray diffraction patterns for annealed sample showed that the addition of Si supress the precipitation of ZrO₂ from Fe matrix and the coarsening of crystallite size. These results are thought to be due to the lameller structure of Si in Fe matrix.