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Title: The metastable disordered [gamma] (TiAl) phase and its ordering process in a rapidly solidified equiatomic TiAl alloy with vanadium addition

Journal Article · · Scripta Metallurgica et Materialia; (United States)
; ;  [1]
  1. Univ. of Surrey (United Kingdom). Dept. of Materials Science and Engineering

The recently Ti-Al phase diagram is characterized by a double peritectic reaction (L + [beta] [minus]> [alpha] and L + [alpha] [minus]>[gamma]) that spreads over a narrow temperature domain. Consequently, near equilibrium'' solidification and rapid solidification studies carried out in binary Ti-(40 to 70at%) Al alloys have shown that several solidification phases (stable or metastable) are accessible with relatively small bulk undercoolings and slight variations in chemical composition. For the tetragonal (c/a = 1.02) ordered L1[sub 0][sub [gamma]] phase, there is growing controversy surrounding both the possibility of the selection of the [gamma] phase in alloys where [gamma] is not the equilibrium primary phase in solidification, and the formation of the ordered L1[sub 0] [gamma] phase via a sequential ordering process from a parent disordered fcc phase.

OSTI ID:
5189099
Journal Information:
Scripta Metallurgica et Materialia; (United States), Vol. 30:7; ISSN 0956-716X
Country of Publication:
United States
Language:
English