| Pure iron soft magnet is widely used in low frequent or direct current electrical equipments and instruments as magnetic components due to its high saturation magnetic induction and Curie point. With the rapid development of electronic technology, it is certain for magnetic components to develop toward complex shape, miniaturization, high dimensional precision and integrated formation with other components. However, it's difficult for traditional die moulding to meet the above demands. Metal powder injection molding (MIM) easily meet the above demands, therefore, MIM processes of pure iron was systematically investigated in this thesis.The theoretical content of stearic acid (SA) in wax-based binder was 0.32wt% by primary calculating, in order to form a molecule layer of content of SA on pure iron powder particle surface. Moreover, the effect of 110wt% SA on the wettability between binder and powder was investigated. These results showed that the wettability became better with the increase of SA content.The effect of mixing times on the homogenization and density of the feedstock was evaluated with mathematical statistics. These results showed that mixing seven or eight times made density of the feedstock nearer to theoretical density as well as good homogenization.The effects of injection pressure and temperature, and dwell pressure on the quality of green compacts were investigated. These results showed that green strength increased with the increase of injection pressure, but green density decreased with the increase of injection temperature, and that green without defects obtained when injection pressure was 14MPa, injection temperature was 125135℃, dwell pressure was 1012MPa and plasticizing time was no more than 30s.The heptane solvent debinding process and its kinetics were investigated. The results showed that debinding at 40℃for 6h was optimal, and that debinding rate was controlled by diffusing in the beginning and then by dissolving and diffusing.The effects of sintering and heat treatment processes on density, pore distribution, microstructure and coercive force of pure iron were investigated. The results showed that the sinter had a high density when it was heated up at a rate of 3℃·min-1 at the temperature between 900℃and 1350℃and was hold at 1350℃for 3h, and that consequent heat treatment improved the homogenization of pore distribution and microstructure, and that the minimum coercive force of the sinter reached 196A·m-1.
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