Characterization and formation mechanism of nanocrystalline (Fe,Ti)3Al intermetallic compound prepared by mechanical alloying

The nanocrystalline (Fe,Ti)3Al intermetallic compound was synthesized by mechanical alloying (MA) of elemental powder with composition Fe50Al25Ti25. The structural changes of powder particles during mechanical alloying were studied by X-ray diffractometry and microhardness measurements. Morphology and cross-sectional microstructure of powder particles were characterized by scanning electron microscopy. It was found that a Fe/Al/Ti layered structure was formed at the early stages of milling followed by the formation of Fe(Ti,Al) solid solution. This structure transformed to (Fe,Ti)3Al intermetallic compound at longer milling times. Upon heat treatment of (Fe,Ti)3Al phase the degree of DO3 ordering was increased. The (Fe,Ti)3Al compound exhibited high microhardness value of about 1050 Hv.