Influence of thermal debinding on the final properties of Fe–Si soft magnetic alloys for metal injection molding (MIM)

• The properties of MIM Fe-Si alloy are influenced by the debinding heating rate.
• The slow debinding led to a lower porosity, lower oxygen content and grain growth.
• The magnetization of the sintered samples improved after a slow thermal debinding.

Metal injection molding (MIM) may be used to produce soft magnetic materials with optimal mechanical and magnetic properties. Unlike other techniques, MIM enables the production of complex and small Fe–Si alloy parts with silicon contents greater than 3% by weight. In MIM process development, it is critical to design a proper debinding cycle not only to ensure complete removal of the binder system but also to obtain improved properties in the final part. This work is a preliminary study on the production of Fe-3.8Si soft magnetic parts by MIM using pre-alloyed powders and a non-industrialized binder. Two different heating rates during thermal debinding were used to study their effect on the final properties of the part. The final properties of the sintered parts are related to thermal debinding. It has been demonstrated that the heating rate during thermal debinding has a strong influence on the final properties of Fe–Si soft magnetic alloys.