High quality sponge iron powder was produced by hydrogen reduction of iron ore powder, which is essentially pure hematite powder with about 0.3% silica and alumina as impurities. The ore powder is singularly free from carbon, sulphur and phosphorus. Efforts were also launched to develop low-coercivity soft magnetic materials (pure iron) for d.c. and low frequency applications. The sponge iron powder was subjected to compaction, high-temperature sintering and suitable post-sintering treatments to get high density (～99% T.D.) with large grain size (ASTM No.= 1). Cylindrical samples (10 mm diameter × 10 mm length) were machined, annealed and were subjected to coercivity measurement. Average coercivity of the samples was measured as 1.60 Oe. This value compares well with the published coercivity values of pure iron. The product qualifies as a potential low-coercivity soft magnetic material. Efforts are on going to reduce the coercivity further by reduction of oxygen and intra-particle porosity.
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