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Title: Ranking the susceptibility to hydrogen-assisted cracking in dissimilar metal welds
Dissimilar metal welds (DMWs) are routinely used in the oil and gas industries for structural joining of high-strength steels to eliminate the need for post-weld heat treatment (PWHT) in field welding. Hydrogen-assisted cracking (HAC) can occur in DMWs during subsea service under cathodic protection. DMWs of two material combinations, 8630 steel/FM 625 and F22 steel/FM 625, produced with two welding procedures, non-temper bead (BS1) and temper bead (BS3), in the as-welded and PWHT conditions were investigated in this study. These DMWs were subjected to metallurgical characterization and testing with the delayed hydrogen cracking test (DHCT) to identify the effects of base metal composition, welding and PWHT procedures on their HAC susceptibility. The HAC susceptibility was ranked using the time to failure in the DHCT at loads equivalent to 90% of the base metal yield strength (YS) and the apparent stress threshold for HAC. A criterion for resistance to HAC in the testing conditions of DHCT was also established. The results of this study showed that 8630/FM 625 DMWs were more susceptible to HAC than the F22/FM 625 DMWs. PWHT did not sufficiently reduce the HAC susceptibility of the 8630/FM 625 and F22/FM 625 BS1 welds. DMWs produced using BS3 performed better than BS1 DMWs. The post-weld heat-treated F22/FM 625 BS3 DMW passed the HAC resistance criterion.  more » « less
Award ID(s):
2052747
PAR ID:
10506630
Author(s) / Creator(s):
;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Welding in the World
Volume:
66
Issue:
8
ISSN:
0043-2288
Page Range / eLocation ID:
1535 to 1550
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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