Influence of annealing on the microstructure of cast TiAl-based alloy

• Autorzy: Lapin J. , Pelachová T.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The aim of the present work is to study the influence of annealing on the microstructure of cast TiAl-based alloy. Design/methodology/approach: Effect of annealing on the microstructure of cast Ti-46Al-8Ta (at.%) alloy was evaluated at temperatures ranging from 700 to 800°C. Fine grain convoluted microstructure of heat treated alloy consisted of small lamellar colonies of α2-Ti3Al (crystal structure D019) intermetallic phase within γ-TiAl (crystal structure L10) phase. Findings: Annealing leads to precipitation of α2 and τ(crystal structure B82) particles at the grain boundaries at the expense of the α2 laths. This process is connected with a depletion of the grain boundaries of Ti and Ta and formation of Al rich γ phase. Lattice parameter a of the γ phase decreases, c increases and aspect ratio c/a increases with increasing time and temperature of ageing. Research limitations/implications: The annealing leads to an increase of lattice parameters a and c and decrease of the aspect ratio c/a of both α2 and τ phases. Originality/value: This work present the effect of long-term annealing on microstructure stability and lattice parameters of coexisting phases in this alloy at temperatures ranging from 700 to 800ºC.

Słowa kluczowe

EN

TiAl; microstructure; ageing; lattice parameters

PL

TiAl; mikrostruktura; starzenie; parametry sieci

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2014
• Tom: Vol. 65, nr 2
• Strony: 53--60
• Opis fizyczny: Bibliogr. 14 poz., rys., tab.

Twórcy

autor

Lapin J.

• Institute of Materials and Machine Mechanics of Slovak Academy of Sciences, Račianska 75, 831 02 Bratislava, Slovak Republic

autor

Pelachová T.

• Institute of Materials and Machine Mechanics of Slovak Academy of Sciences, Račianska 75, 831 02 Bratislava, Slovak Republic
• Faculty of Materials Science and Technology in Trnava, Slovak University of Technology in Bratislava, Paulínska 16, 917 24 Trnava, Slovak Republic

Bibliografia

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