SEM, 2019, #4, 44-50 pages
Publisher International Association «Welding»
ISSN 2415-8445 (print)
Issue № 4, 2019 (November)
Structure of intermetallic titanium alloy of Ti–Al–Nb–Cr system
V.A. Kostin, G.M. Grigorenko
E.O. Paton Electric Welding Institute of the NAS of Ukraine.
11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: email@example.com
The paper deals with alloys based on titanium aluminides, which are modern promising materials for manufacturing parts and mechanisms in ship-building, mechanical engineering, aviation and aerospace engineering. Cold-hearth electron beam melting is the main method to produce sound ingots of intermetallics based on Ti–Al system. Structure and properties of an intermetallic alloy of Ti–Al–Nb–Cr system were studied, and calculated equilibrium state diagram was plotted. It is shown that in the ingot central part the alloy structure consists approximately of 85…90 vol. % of (γ + α2
)-phase, massive sections of γ-phase of about 10 vol. %, as well as small fraction of 3…5 vol. % of cubic B2-phase, located along the grain boundaries. CALPHAD methodology was used to plot the equilibrium ternary state diagrams of Ti–Al–Nb–Cr systems. Ref. 15, Tabl. 2, Fig. 4.
Key words: titanium alloys; electron beam melting; intermetallics; titanium aluminides; phase transformations; ternary state diagrams
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