Contribution of shear deformation to grain refinement and densification of iron powder consolidated by high pressure torsion

摘要: High Pressure Torsion (HPT) experiments were performed for consolidation of water-atomized pure iron powder (99%) with initial particle sizes 20-100 gm. The carried out successfully at room temperature, achieving both low level residual porosity and significant grain refinement, thanks to the intense shear strain hydrostatic pressure applied in HPT. X-ray diffraction analysis was on consolidated samples which revealed no proportion oxides. Considering inherent heterogeneity imposed HPT, different positions across diameters sample disks selected mechanical property microstructure investigations. effect deformation texture investigated by metallography, scanning electron microscopy, backscattered (EBSD). micro-hardness as a function constant also measured. size distributions showed homogeneous microstructures refinement due deformation. measurements that typical bcc obtained during HPT compaction powder.