Magnetic properties of Fe–50%Ni alloy fabricated by metal injection molding

Fe–50%Ni soft magnetic alloys are attractive in their applications with both low coercivity and high permeability. Their magnetic properties are closely related to sintering conditions. In this paper, Fe–50%Ni soft magnetic alloys were successfully produced by metal injection molding using carbonyl iron and carbonyl nickel as raw materials. The effects of sintering temperature, sintering atmosphere and time on the magnetic properties of the alloy were investigated. Special attention was paid to the influence that sintering conditions have on chemistry and the resulting effects on magnetic properties. The results indicated that the magnetic permeability was greatly dependent on the content of interstitial atom such as C, O, and N and the density was a major factor affecting the saturation induction. Furthermore, the effects of processing condition on the microstructures of Fe–50%Ni alloy were shown. The optimum magnetic properties for Fe–50%Ni alloy were obtained by maximizing density and sintering temperatures, and minimizing the contamination levels of C, O and N.