Transmission electron microscopy characterization of thermomechanically treated Al₃Ti-(8, 10, 15)% Cr intermetallics.

The ordered L1₂-type Al₃Ti-(8, 10, 15)% Cr intermetallic compounds, namely, Al₆₇Ti₂₅Cr₈, Al₆₆Ti₂₄Cr₁₀, and Al₅₉Ti₂₆Cr₁₅, were prepared by induction melting followed by thermomechanical treatment. Their microstructure, compositional variation, and crystal structure were characterized using X-ray diffraction, optical microscopy, and scanning and transmission electron microscopy equipped with energy-dispersive spectroscopy. The Al₆₇Ti₂₅Cr₈ alloy consisted of the L1₂-Al₃Ti matrix and precipitates of α₂-Ti₃Al, D0₂₂-Al₃Ti, and γ-TiAl. The Al₆₆Ti₂₄Cr₁₀ and Al₅₉Ti₂₆Cr₁₅ alloys consisted of the L1₂-Al₃Ti matrix and grains of α-TiAl and β-Cr.