Al 13 Fe 4 -Al Composites with Nanocrystalline Matrix Manufactured by Hot-Pressing of Milled Powders.

The paper describes composites with the matrix containing a nanocrystalline intermetallic Al 13 Fe 4 phase and microcrystalline aluminium. Mechanically alloyed Al 80 Fe 20 powder, containing a metastable nanocrystalline Al 5 Fe 2 phase, was mixed with 20, 30, and 40 vol.% of Al powder and consolidated at 750 °C under the pressure of 7.7 GPa. During the consolidation, the metastable Al 5 Fe 2 phase transformed into a nanocrystalline Al 13 Fe 4 phase. In the bulk samples, Al 13 Fe 4 areas were wrapped around by networking Al regions. The hardness of the Al 13 Fe 4 -Al composites was in the range of 4.52-5.50 GPa. The compressive strength of the Al 13 Fe 4 -30%Al and Al 13 Fe 4 -40%Al composites was 805 and 812 MPa, respectively, and it was considerably higher than that of the Al 13 Fe 4 -20%Al composite (538 MPa), which failed in the elastic region. The Al 13 Fe 4 -30%Al and Al 13 Fe 4 -40%Al composites, in contrast, showed some plasticity: namely, 1.5% and 9.1%, respectively. The density of the produced composites is in the range of 3.27-3.48 g/cm 3 and decreases with the increase in the Al content.