Highly dense steel components prepared by magnetic pulsed compaction of iron-based powders

Abstract

Magnetic pulsed compaction (MPC) was introduced to consolidate conventional iron-based powders for the production of high-density steel parts in powder metallurgical (PM) processing. Highly dense steel components of Fe–1.5Cr–0.2Mo–0.25C (wt.%) were obtained with green and sintered densities of 7.63g/cm3 and 7.75g/cm3 (full density: 7.8g/cm3). This anomalous densification in the MPC process was attributed to the complementary kinetic effect by the high impact pressure in a very short duration, allowing the enhanced particle rearrangement and plastic deformation in the compacted powders. Owing to this superior compactability, the intact compacts were fabricated efficiently even with the small addition of lubricant (less than 0.05wt.%). Also, die wall lubrication was effective for preventing surface damage as well as for promoting homogeneous densification during the MPC. These results show a potential for application of the MPC process to high-density steel PM parts.