Carbonyl iron power premix composition

Abstract

A carbonyl iron powder (CIP) premix composition suitable for metal injection molding is provided herein. The composition comprises (a) CIP having a particle size in the range of about 0.2-7 microns, preferably about 0.2-5 microns, and a narrow particle size distribution; and (b) an alloying material, having a particle size in the range of about 0.02 to 5 microns, preferably about 0.03 to 3.0 microns, and a narrow particle size distribution, comparable to the CIP, and present in an amount of about 0.1-60% by weight of the composition, preferably 0.5-50%. The alloy material substantially covers the surface of the iron particles and is adhered thereto by attractive forces. Preferably the alloy material includes elemental metal powders which are smaller in particle size than the CIP. The premix composition is prepared by intensive mixing of its powder components, e.g. by attritor milling at high speeds for an extended period of time, which reduces the particle size distributions of the powders and avoids alloy segregation during sintering.

Dependencies are inferred from the claim text.