Influence of Nb, Ta and Zr on the Interdiffusion Coefficients and Solid Solution Strengthening of γ-TiAl Single Phase Alloys

Haußmann L, Neumeier S, Bresler J, Keim S, Pyczak F, Göken M (2022)

Publication Type: Journal article

Publication year: 2022

Journal

Metals MDPI

Book Volume: 12

Article Number: 752

Journal Issue: 5

DOI: 10.3390/met12050752

Abstract

The alloying elements Nb, Ta and Zr improve the creep properties of fully lamellar γ/α2 titanium aluminides significantly. Since high temperature deformation mainly occurs in the γ-phase of γ/α2 titanium aluminides, the diffusivity and the solid solution hardening effect of these three elements in the γ-phase is studied by analyzing the concentration gradients of the alloying elements and the resulting hardness across the interdiffusion zone of diffusion couples by energy dispersive X-ray diffraction and nanoindentation. The results reveal that Zr has the highest interdiffusion coefficient but also the largest solid solution hardening coefficient. The mechanical properties of single γ-phase Ti-54Al-5X alloys were investigated by strain rate jump tests. The addition of 5 at.% Nb or Ta lead to an increased strength compared to a binary γ-Ti-54Al alloy. The Zr-containing γ-TiAl alloy reveals the highest strength at 750°C and 900°C, which is discussed to be due to the strong solid solution hardening effect of Zr. However, in comparison to the other alloys, Ti-54Al-5Zr shows quite brittle behavior up to 900°C. The lower diffusivity of Ta compared to Nb leads to a higher strength of the Ta-modified alloy at 900◦C.

Authors with CRIS profile

Lukas Haußmann Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Steffen Neumeier Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Johannes Bresler Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Mathias Göken Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Involved external institutions

Helmholtz-Zentrum Hereon DE Germany (DE)

How to cite

APA:

Haußmann, L., Neumeier, S., Bresler, J., Keim, S., Pyczak, F., & Göken, M. (2022). Influence of Nb, Ta and Zr on the Interdiffusion Coefficients and Solid Solution Strengthening of γ-TiAl Single Phase Alloys. Metals, 12(5). https://dx.doi.org/10.3390/met12050752

MLA:

Haußmann, Lukas, et al. "Influence of Nb, Ta and Zr on the Interdiffusion Coefficients and Solid Solution Strengthening of γ-TiAl Single Phase Alloys." Metals 12.5 (2022).

BibTeX: Download