A new intermetallic compound in TiAl+Nb composition area of the Ti–Al–Nb ternary system

Nano-mechanical characterization of plasma surface tungstenized layer by depth-sensing nano-indentation measurement

“…Moreover, the remarkable rapid development of the space industry has put forward demanding requirements on the surface mechanical properties of Ti-Al-Nb alloys. To obtain consistently reliable performance in harder and more durable Ti-Al-Nb alloys, designers are constantly searching for a modification method of the alloy surface [4,5]. As an effective and economical method, the double-glow plasma surface alloying process can improve the mechanical performances of metal or alloy surface and enhance such indicators as micro-hardness, corrosion resistance, wear resistance, oxidation resistance, etc [6][7][8].…”

Interpretation of the morphology and crystallography of precipitate γ1-Ti4Nb3Al9 in L10-TiAl(Nb)-based intermetallics by invariant line theory

“…The literature [10] and [11] have shown the same crystallography and morphology of the g 1 -Ti 4 Al 3 Nb 9 equilibrium phase in a Ti 4 Al 3 Nb 9 alloy. However, the direction of the phase takes h111] compared with that of precipitated phase taking [001] revealed in this study.…”

“…Hellwig et al [8] and Chen et al [9] have reported the diagram of the 1273 K, 1473 K and 1673 K isothermal sections of the TieAleNb system. Crystallographic structure of the phase Ti 4 Nb 3 Al 9 (g 1 ) equilibrium phase was then reported by Chen et al [10]. The L1 0 -TiAl phase is of an ordered face-centered tetragonal structure with parameters a ¼ 0.3976 nm and c ¼ 0.4049 nm.…”

“…For a phase transformation system of g 1 -Ti 4 Al 3 Nb 9 (precipitate, tetragonal (T))/L1 0 -TiAl(Nb) (matrix, face-centered tetragonal (FCT)), the lattice correspondence can be regarded as type of FCT to body-centered tetragonal (BCT) based on the fact that the unit cell of the phase g 1 -Ti 4 Al 3 Nb 9 contains eight small BCT cells [10] shown in Fig. 3(a).…”

High temperature deformation behaviors of a high Nb containing TiAl alloy

“…Many valuable conclusions, including oxidation resistance [1], phase relationships and phase diagram construction [2], microstructure evolution [3], relationships of microstructures and properties [4] and workability at high temperatures [5], have been reported previously. It is worth noting that the TiAl alloys with Al content ranging from 45 to 49 at.% and Nb content ranging from 8 to10 at.% exhibit excellent balanced properties.…”