Iron Powders for Additive Manufacturing and Metal Injection Molding Produced by an Environmentally Friendly Route from Steel-Production Sourced Ore Wastes

The demand for small, spherical powders for additive manufacturing as well as for metal injection molding increases. For particles ≤ 10 µm, mainly two production routes exist: atomization and the carbonyl process. The production of such powders is costly, so alternatives are needed. We present developments in a solid-state processing route using iron ore from the steel steeping process that otherwise might end up as waste. To scale up the production to hundreds of kilograms per day, granules obtained by wet spraying are reduced and sintered in a rotary kiln to form porous but stable agglomerates, and post treated in a NARA hybridizer mill to form dense particles. Pure iron particles with < 0.2 m% oxygen, an apparent density of ≈ 3 g/cm3 and a purity of > 98 % are obtained at an expected cost level of less than 3 €/kg.