Development of powder injection molding process for sintered soft magnet with the addition of Fe-17Â at.% P powder

Soft magnetic powder injection molding is a net-shape production technology to fabricate sintered soft magnets. Powder injection molding technology for soft magnetic materials can be expected to develop a new type of electromagnetic components with the miniaturization and complexity design. In this work, 8 wt.% of iron-phosphorus powders (Fe-17 at.% P) were added to carbonyl iron powders to improve the magnetic performances with PIM process. Soft magnetic feedstocks were fabricated by optimized PIM process using a wax-based binder system. The critical solids loading of feedstocks were measured to determine the optimal solids loading, and injection molding process was conducted for the PIMed soft magnetic parts. The effect of Fe-17 at.% P addition to carbonyl iron powder was investigated on the sintering behaviors and magnetic properties. It was observed that sample with Fe-17 at.% P addition had optimum relative density (99.8%) and magnetic polarization (28,299 Gauss) at sintering temperature 1400°C in a hydrogen atmosphere.