Iron-based Soft Magnetic Materials Fabricated by Laser Additive Manufacturing
Abstract
In the present study, soft magnetic materials were prepared by coating Fe-based magnetic powder core with inorganic insulating materials such as phosphoric acid, manganese nitrate and sodium molybdate. The prepared iron-based powders were effectively printed and shaped by laser additive manufacturing. The composition and microstructure of the soft magnetic materials were analyzed to assess changes in the magnetic properties. Compared with those of the sample prepared by traditional molding, these samples prepared by laser additive manufacturing exhibit excellent magnetic properties, including good saturation magnetic induction (1.6 T), magnetic permeability (μm=1923) and saturation magnetization (203.69 emu/g). The comprehensive properties of soft magnetic composites are improved by changing the composition of phosphoric acid passivation solution. It is found that the coercivity of iron based soft magnetic materials formulated by phosphoric acid passivation solution containing manganese nitrate and sodium molybdate was obviously reduced to 154.6 A/m.