Cart (Loading....) | Create Account
Close category search window

Thermal vacancy formation and positron–vacancy interaction in Ti3Al at high temperatures

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $31
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Wurschum, R. ; Institut für Theoretische und Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany ; Kummerle, E.A. ; Badura‐Gergen, K. ; Seeger, A.
more authors

Your organization might have access to this article on the publisher's site. To check, click on this link: 

In order to study the formation of thermal vacancies in the Ti–Al alloy system, high‐temperature positron lifetime measurements together with a modeling of defect formation in the framework of nearest‐neighbor pair bonds were performed for α2Ti3Al and compared to recent results on γTiAl [U. Brossmann, R. Würschum, K. Badura, and H.‐E. Schaefer, Phys. Rev. B 49, 6457 (1994)]. Substantial increases of the positron lifetime τ were observed for Ti65.6Al34.4 and Ti77.1Al22.9 in the temperature range T≳1200 K where thermal vacancy concentrations above the detection limit of positron annihilation are expected from the model calculations for the α2 phase. Within the high‐temperature increase of the positron lifetime in the α2 and the β phase single‐component positron lifetime spectra were observed. This behavior is in contrast to the two‐component spectra observed conventionally at intermediate positron trapping rates and is attributed to a fast detrapping and retrapping of positrons at vacancies due to a low positron–vacancy binding energy. For this case, a vacancy formation enthalpy of HFV=(1.55±0.2) eV in α2Ti65.6Al34.4 and HFV=(1.8±0.2) eV in βTi77.1Al22.9 can be derived. These results are discussed in the context of recent 44Ti tracer diffusion studies. © 1996 American Institute of Physics.

Published in:

Journal of Applied Physics  (Volume:80 ,  Issue: 2 )

Date of Publication:

Jul 1996

Need Help?

IEEE Advancing Technology for Humanity About IEEE Xplore | Contact | Help | Terms of Use | Nondiscrimination Policy | Site Map | Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest professional association for the advancement of technology.
© Copyright 2014 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.