Warm compaction of attrition milled nanostructured iron powders

Attrition milled, nanostructured iron-based powders were compacted at temperatures less than one half the melting temperature and at pressure in excess of 1GPa and resulted in full dense samples from which macroscopic properties could be determined. The use of modest compaction temperatures resulted in (1) reducing the mechanical induced lattice strain, (2) producing interparticle bonding by grain boundary diffusion, and (3) limiting grain growth. The high compression stress resulted in deforming the milled particles into a fully dense compact. Hall-Petch relationships for the compacts were consistent with data from previous studies.