The influence of niobium, tantalum and zirconium on the microstructure and creep strength of fully lamellar gamma/alpha(2) titanium aluminides

Bresler J, Neumeier S, Ziener M, Pyczak F, Göken M (2019)

Publication Status: Published

Publication Type: Journal article

Publication year: 2019

Journal

Publisher: ELSEVIER SCIENCE SA

Book Volume: 744

Pages Range: 46-53

DOI: 10.1016/j.msea.2018.11.152

Abstract

Titanium aluminides are excellent materials for light-weight applications at high temperatures. To enhance their creep strength, various alloying elements are added. In this work the effect of 5 at% Niobium (Nb), Tantalum (Ta) and Zirconium (Zr) on the creep properties of ternary Ti-44Al-5X (X = Nb, Ta, Zr) with a fully lamellar microstructure, is systematically studied. These alloying elements have a high solubility in titanium aluminides, and show a different alpha(2)/gamma partitioning behavior as well as a different influence on the lattice parameters of both phases. The average interface distance between the alpha(2)- and gamma-phase is adjusted to about 300 nm by the cooling rate to evaluate the influence of the three alloying elements. The creep tests reveal that all three alloying elements increase the creep resistance of titanium aluminides, particularly Ta and Zr. Ta seems to extend the pronounced primary creep regime, whereas Zr seems to reduce it The alloying elements decrease also the lamellar spacing compared to the binary alloy. Microstructural investigations after the creep tests show a beneficial effect of the alloying elements on the microstructural stability during creep exposure, since they retard the discontinuous coarsening rate.

Authors with CRIS profile

Involved external institutions

Helmholtz-Zentrum Geesthacht Zentrum für Material- und Küstenforschung GmbH (HZG) Germany (DE)

How to cite

APA:

Bresler, J., Neumeier, S., Ziener, M., Pyczak, F., & Göken, M. (2019). The influence of niobium, tantalum and zirconium on the microstructure and creep strength of fully lamellar gamma/alpha(2) titanium aluminides. Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 744, 46-53. https://doi.org/10.1016/j.msea.2018.11.152

MLA:

Bresler, Johannes, et al. "The influence of niobium, tantalum and zirconium on the microstructure and creep strength of fully lamellar gamma/alpha(2) titanium aluminides." Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing 744 (2019): 46-53.

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