Preparation of Ti-Al and Fe-Al Alloys by Mechanical Alloying

Abstract

This work aims to describe the formation of intermetallics in Ti-Al and Fe-Al systems during ultra-high energy mechanical alloying process developed by authors. Although both systems tend to form aluminides, the formation of the phases during mechanical alloying is different. It was found that TiAl38 (in wt.%) powder mixture forms dual-phase TiAl/Ti3Al structure, which is consequently transformed to almost single-phase TiAl structure as the duration of mechanical alloying increases. On the other hand, FeAl32 (in wt.%) powder mixture formed ordered FeAl phase in the early steps, which was consequently changed to disordered solid solution after longer milling.

Synthesis of Intermetallics in Fe-Al-Si System by Mechanical Alloying

“…It was then converted to FeAl ordered phase (B2 structure) by the reaction with iron and only the FeAl phase was detected after 1 h of milling. Further prolongation of the milling did not cause any changes in the phase composition [28].…”

“…In the case of FeAl32 binary alloy, the mechanical alloying led to the temporary formation of FeAl 3 phase after 0.5 h of milling [28]. This phase, as well as Fe 2 Al 5 are known as transient phases formed by Fe + Al reaction in reactive sintering synthesis of FeAl phase [29].…”