Abstract
The iron-cobalt based alloys (especially Permendur) have been widely used for the application requiring high saturation induction, high permeability, low coercive force and high Curie temperature. Although the quantity of material so used has not been large, the reduction in the size and weight of apparatus that can be accomplished by its use has had an important effect on technical developments. Magnetic characteristics of Fe-50Co ring samples produced by the conventional powder metallurgy process with spray drying method were investigated. After pure elemental powders of iron and cobalt were mixed, these powders were granulated by spray drying method using organic binder consisting of polyvinylalcohol (PVA) and plasticizer in the range from O.1wt% to 0.5wt% of PVA, in order to improve the powder flowability during feeding and compacting. The resulting magnetic properties are superior to those of the MIM (Metal Injection Molding) 49Fe-49Co-2V alloy, and its magnetic induction at a magnetic field of 2000A/m exhibits the same value as that of commercial wrought 49Fe-49Co-2V alloy. Results show that the present method is an excellent process of producing near-net-shape parts with high saturation induction and low coercivity.
