Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Hydrogen trapping in T24 Cr-Mo-V steel weld joints—microstructure effect vs. experimental influence on activation energy for diffusion

Hydrogen trapping in T24 Cr-Mo-V steel weld joints—microstructure effect vs. experimental... Hydrogen-assisted cracking is a critical combination of local microstructure, mechanical load and hydrogen concentration. Welded microstructures of low-alloyed creep-resistant Cr-Mo-V steels show different hydrogen trapping kinetics. This influences the adsorbed hydrogen concentration as well as the diffusion by moderate or strong trapping. A common approach to describe hydrogen traps is by their activation energy that is necessary to release hydrogen from the trap. In the present study, Cr-Mo-V steel T24 (7CrMoVTiB10-10) base material and TIG weld metal were investigated. Electrochemically hydrogen charged specimens were analyzed by thermal desorption analysis (TDA) with different linear heating rates. The results show two different effects. At first, the microstructure effect on trapping is evident in terms of higher hydrogen concentrations in the weld metal and increased activation energy for hydrogen release. Secondly, it is necessary to monitor the real specimen temperature. A comparison between the adjusted heating rate and the real specimen temperature shows that the calculated activation energy varies by factor two. Thus, the trap character in case of the base material changes to irreversible at decreased temperature. Hence, the effect of the experimental procedure must be considered as well if evaluating TDA results. Finally, realistic temperature assessment is mandatory for calculation of activation energy via TDA. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Welding in the World Springer Journals

Hydrogen trapping in T24 Cr-Mo-V steel weld joints—microstructure effect vs. experimental influence on activation energy for diffusion

Loading next page...
 
/lp/springer_journal/hydrogen-trapping-in-t24-cr-mo-v-steel-weld-joints-microstructure-FXdz5JqH7B

References (58)

Publisher
Springer Journals
Copyright
Copyright © 2018 by International Institute of Welding
Subject
Materials Science; Metallic Materials; Continuum Mechanics and Mechanics of Materials; Theoretical and Applied Mechanics
ISSN
0043-2288
eISSN
1878-6669
DOI
10.1007/s40194-017-0546-6
Publisher site
See Article on Publisher Site

Abstract

Hydrogen-assisted cracking is a critical combination of local microstructure, mechanical load and hydrogen concentration. Welded microstructures of low-alloyed creep-resistant Cr-Mo-V steels show different hydrogen trapping kinetics. This influences the adsorbed hydrogen concentration as well as the diffusion by moderate or strong trapping. A common approach to describe hydrogen traps is by their activation energy that is necessary to release hydrogen from the trap. In the present study, Cr-Mo-V steel T24 (7CrMoVTiB10-10) base material and TIG weld metal were investigated. Electrochemically hydrogen charged specimens were analyzed by thermal desorption analysis (TDA) with different linear heating rates. The results show two different effects. At first, the microstructure effect on trapping is evident in terms of higher hydrogen concentrations in the weld metal and increased activation energy for hydrogen release. Secondly, it is necessary to monitor the real specimen temperature. A comparison between the adjusted heating rate and the real specimen temperature shows that the calculated activation energy varies by factor two. Thus, the trap character in case of the base material changes to irreversible at decreased temperature. Hence, the effect of the experimental procedure must be considered as well if evaluating TDA results. Finally, realistic temperature assessment is mandatory for calculation of activation energy via TDA.

Journal

Welding in the WorldSpringer Journals

Published: Jan 8, 2018

There are no references for this article.