| Consolidation of rapidly solidified (RS) particles in particular chopped Al94Fe2V4 melt-spun ribbons (MSR) and ultra-fine Al 99,7% powders (d50=1.3 µm) was performed in order to obtain bulk profiles for structural applications requiring high strength and thermal stability at elevated temperatures above 200 œC accompanied with sufficient ductility and toughness. Equal Channel Angular Pressing (ECAP) method was investigated as an alternative to conventionally used compaction via hot direct extrusion (DE). The experiments have shown, that ECAP enables introduction of sufficient shear deformation necessary for establishing sound metallurgical bonds between particles at significantly lower compaction pressures than DE performed at the same temperatures. This allows compaction of Al-based particles at lower temperatures, thus maintaining their desired RS structure. Satisfactory compaction of both types of RS particles was attained already after one ECAP pass resulting in higher microhardness and density than in a case of DE at the same temperature, whereas the properties can be still further enhanced by multiple ECAP passes. |
full paper (pdf, 640 Kb)