time and again, we find that the nickel content of failed 316 is below specification, until… Thanks to Josh Lyons of the Thaitanium Project for the heap of corroded hardware pulled from the walls of Railay/Tonsai. Without such real world samples, all is mere speculation. We find a broken bolt from Railay/Tonsai which is absolutely […]
Tag: SSC
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Thailand Crags – 2
Sulphide Stress Cracking (SSC) The second part of a multi-part series For SCC see Part 1 Tonsai/Railay is where stainless-steel anchors go to die. We can now add, that the cause is SRB-mediated SSC. Introduction: I owe much to Martin Roberts of Titan Climbing for taking the initial steps of our great adventure into crag chemistry. […]
Is there a problem with severe bolt corrosion on Kalymnos… yeah?… nah? Let’s review what we know. Many thanks to Jorge Jordan for sending me the broken bolt, and thanks also to Emanuele Pellizzari for the wall-wash samples. Introduction: In September of last year, Facebook lit up with a report of a bolt failure at […]
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Thailand Crags – 1
Chasing Some Demons The first Part of a multi-Part Series Introduction: Tonsai/Railay is where stainless-steel anchors go to die. So, this is where it all began. Actually, I tell a lie, it began elsewhere, but, as far as notoriety within the climbing community is concerned, our story begins many years ago on the tropical beaches […]
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Now This Is Different
An example of an SS anchor chain exhibiting marked resistance to SRB attack Many thanks to Luis Fernandes Silva for the sample. On previous occasions I have reported on the sulphate-rich sea cliffs of Cabo da Roca. They are notorious for the aggressive corrosion of low grade austenitic stainless steels such as 304 (A2). Sulphate […]
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SSC vs SCC
Thanks to Luis Fernandes Silva for providing the sample. Which is it, sulphide stress cracking (SSC) or chloride-induced stress corrosion cracking (SCC)? I raised this question in one of my earlier posts where I described the aggressive corrosion of stainless steel at Cabo da Roca. In that particular post I highlighted the main differences between […]
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Corrosion at Cabo da Roca – 2
Sulphide Stress Cracking The second part of a multi-part series In conducting this work I have been greatly assisted by Luis Fernandes Silva and Rui Rosado who have provided multiple samples and photos for analysis. Luis has spent a great deal of time measuring spot-sulphate levels, and the pH profiles of bolts he has extracted […]
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Corrosion at Cabo da Roca – 1
The story of a sulphate crag The first part of a multi-part part series In conducting this work I have been greatly assisted by Luis Fernandes Silva and Rui Rosado who have provided multiple samples and photos for analysis. Luis has spent a great deal of time measuring spot-sulphate levels, and the pH profiles of […]