Effect of Mo addition on transformation behavior of (α 2 + γ) based Ti–Al alloys

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 429; no. 1; pp. 219 - 224
• Main Authors: Azad, Shankar, Mandal, R.K., Singh, A.K.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.08.2006; Elsevier
• Subjects: B2 phase; Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Microstructure; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Phase transformations; Physics; Ti–Al–Mo alloys; X-ray diffraction; β Stabilizer; B2 phase; X-ray diffraction; β Stabilizer; Ti–Al–Mo alloys; Phase transformations; Microstructure; Phase composition; Intermetallic compounds; Water quenching; Niobium alloys; XRD; Heat treatments; Cast alloy; Structural models; Solution heat treatment; Titanium alloys; Aluminium alloys; Ti-Al-Mo alloys; Chemical composition; Molybdenum alloys
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2006.05.077

The structural and microstructural characterizations of four alloys with nominal compositions of Ti–42Al–2Mo, Ti–42Al–6Mo, Ti–40Al–2Mo, and Ti–40Al–6Mo have been studied. The 2 at.% Mo as cast alloys comprise of (α 2 + γ) phases whereas those of 6 at.% Mo show (B2 + γ) phases. The solution treatment at 1300 and 1400 °C for 1 h followed by water quenching of these alloys have shown composition specific phase transformation characteristics. The formation of the B2 phase during heat treatment has been discussed and structural model based on statistical occupancy to explain (1 0 0) peak will be presented. The change in the nature of bonding of the B2 phases in Ti–Al–M (M = Mo, Nb, V) alloys have been highlighted.