Effect of 2–6 at.% Mo addition on microstructural evolution of Ti-44Al alloy. Issue 7 (July 2018)

• Record Type: Journal Article
• Authors: Zhang, S.Z.; Song, Z.W.; Han, J.C.; Zhang, C.J.; Lin, P.; Zhu, D.D.; Kong, F.T.; Chen, Y.Y.
• Is Part Of: Journal of materials science & technology. Volume 34:Issue 7(2018)
• Page Start: 1196
• Page End: 1204
• Publication Date: 2018-07
• Subjects: Phase transformation -- Titanium aluminides -- Heat treatment -- Microstructure evolution -- β/β0 phase; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2017.10.012
• Languages: English
• ISSNs: 1005-0302

Abstract

Abstract: In order to understand the effect of Mo alloying on the microstructural evolution of TiAl alloy, the as-cast microstructure, heat treated microstructure characteristic, and hot compression microstructure evolution of Ti-44Al alloy have been studied in this work. The as-cast microstructure morphology changes from ( γ +α2 ) lamellar colony and β / β 0 + γ mixture structure to β / β 0 phase matrix widmannstatten structure, when Mo content increases from 2 at.% to 6 at.%. Affected by the relationship between β phase and α phase, the angles between the lamellar orientation and the block β / β 0 phase are roughly at 0°, 45° and 90°. Comparing with heat treatment microstructure, the hot compression microstructure contains less β / β 0 phase, however, the β / β 0 phase containing 2Mo alloy and 3Mo alloy hot compressed at 1275 °C has the inverse tendency. In addition, (α2 + γ ) colony is decomposed by the discontinuous transformation.