Abstract
Thermit reaction and its use to dispersion strengthening of aluminum has been studied in mechanically alloyed Al-Fe3O4. Al-Cr2O3 and Al-MoO3 systems. Differential thermal analysis shows that thermit reaction occurs in Al-Fe3O4 at temperatures above 610°C, whereas reaction is not observed both in Al-Cr2O3 and Al-MoO3 at temperatures up to the melting point of aluminum (660°C). Dispersion strengthning by the thermit reaction products is studied in extrudates of the mechanically alloyed Al-Fe3O4 powder: annealing above 610°C brings out increases in hardness and tensile strength. lt is shown that thermit reaction in mechanically alloyed aluminum-metallic oxide composites is successfully applicable for dispersion strengthening of aluminum for elevated temperature services.
