Oxygen diffusion coefficient in the γ phase of a TiAl GE alloy determined by SIMS

• Published in: Intermetallics Vol. 172; p. 108367
• Main Authors: Thenot, Camille, Monceau, Daniel, Connétable, Damien, Sallot, Pierre, Pinault-Thaury, Marie-Amandine, Monchoux, Jean-Philippe
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2024; Elsevier
• Subjects: Condensed Matter; Diffusion; Intermetallics (aluminides, silicides); Materials Science; Physics; Secondary ion mass spectrometry; Intermetallics (aluminides, silicides); Diffusion; Secondary ion mass spectrometry; Intermetallics (aluminides silicides)
• ISSN: 0966-9795; 1879-0216
• DOI: 10.1016/j.intermet.2024.108367

First reliable experimental oxygen diffusion coefficient data have been obtained in a Ti48.3Al47.7Cr1.9Nb2.1 near-γ GE alloy through secondary ion mass spectrometry (SIMS) depth profiling measurements of 18O isotopes between 500 °C and 700 °C. The following expression of diffusion coefficient D has thus been derived: D(m2/s)=10−10.6±1∙exp(−107±10kJ.mol−1/RT). These data have been compared with theoretical calculations from literature, showing reasonable agreement concerning the activation energy, but significant discrepancy regarding the D values. •Oxygen diffusion coefficients in the γ phase of TiAl are reliably determined.•18O diffusion experiments and SIMS depth profiling characterizations are implemented.•The experimental results are compared with literature theoretical predictions.