This paper presents a review hydrogen-induced cracking (HIC) of Ti Grade 7 and other relevant titanium alloys under nuclear waste repository environmental conditions, with a primary emphasis on the corrosion processes possible in aqueous environments at Yucca Mountain. The current understanding of hydrogen absorption and the role of passive film on titanium alloys is presented. The key corrosion processes that could occur are addressed individually. Finally, the models developed to assess the hydrogen concentration in the drip shield due to passive general corrosion and galvanic coupling to less noble metals under repository conditions is described. To facilitate the discussion, Ti Grades 2, 5, 7, 9, 11, 12, 16, 17, 18, and 24 are included in this review. It can be concluded that under repository conditions, HIC of titanium alloys will not occur because there will not be sufficient hydrogen in the metal even after 10,000 years of emplacement. Based on the many assumptions adopted this assessment can be considered very conservative.

Subject
Acids, Materials, Absorption, Hydrogen concentration, Corrosion rate, Hydrogen absorption, Titanium oxide, Acidity, Metals, Titanium, Risk reduction, Titanium alloys, Hydrogen
Keywords:
Titanium Alloys, Nuclear Waste, Palladium, Hydrogen-Induced Cracking
© 2005 Association for Materials Protection and Performance (AMPP). All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photocopying, recording, or otherwise) without the prior written permission of AMPP. Positions and opinions advanced in this work are those of the author(s) and not necessarily those of AMPP. Responsibility for the content of the work lies solely with the author(s).
2005
Association for Materials Protection and Performance (AMPP)
You do not currently have access to this content.