stress- corrosion crack initiation of high-strength pipeline steel in near-neutral ph environments
نویسندگان
چکیده
stress-corrosion cracking (scc) tests were conducted in the near-neutral ph standard solution, ns4, and in an actual soil solution, using four-point bending at a high stress ratio and low frequency conditions very similar to those of operational pipelines. pitting incubation appeared first and then pitting initiated and grew in both solutions although there were many more pits on the specimen tested in soil purged with 5% co2 +95%n2 than in the specimen tested in ns4 solution purged with the same gas. these observations show that samples in soil solution are more susceptible to pitting than those in ns4 solution. when the pit reached a critical size, the increased stress concentration around the pits, resulted in transition to a crack.
منابع مشابه
Stress- Corrosion Crack Initiation of High-strength Pipeline Steel in Near-neutral pH Environments
Stress-corrosion cracking (SCC) tests were conducted in the near-neutral pH standard solution, NS4, and in an actual soil solution, using four-point bending at a high stress ratio and low frequency conditions very similar to those of operational pipelines. Pitting incubation appeared first and then pitting initiated and grew in both solutions although there were many more pits on the specimen t...
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عنوان ژورنال:
international journal of iron & steel society of iranناشر: iron & steel society of iran
ISSN 1735-4145
دوره 3
شماره 1 2006
کلمات کلیدی
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