| Popis: |
Spray-quenched amorphous powders of the alloy Ni49Fe29P14B6Al2 were consolidated by uniaxial warm die pressing into disc samples at different temperatures T below the crystallization temperature Tx under a compacting pressure σ of 0.98 GPa. The homogeneous-to-inhomogeneous transition temperature Tx of deformation of the powders was determined from analysis for the ln e vs. 1/T plot (where e is the strain rate of the powders during compaction). Densification of compacts of the present alloy has been found to proceed markedly as the compacting temperature exceeds the temperature Tp, from observations of the cross-sections of compacts; there were only a few voids in the compacts produced from amorphous powders below 46 μm in size at a temperature approximately 30 K above Tp. These results suggest that densification of the compact of an amorphous alloy powder by warm consolidation is achieved even at temperatures several tens of kelvins above Tp, i.e. well below Tp, if, in particular, the size and shape of the powder used and the compacting pressure and time are appropriate. |
