Marine Atmospheric SCC of Unsensitized Stainless Steel Rock Climbing Protection

A failure investigation into the root cause of fixed austenitic stainless steel climbing anchor hardware in tropical marine climates has been presented. The incident 316L climbing anchor was fixed in a seaside limestone cliff in southern Thailand and underwent transgranular chloride stress corrosion cracking (TGSCC) after 10 years of service. Since stainless steel does not normally undergo stress corrosion cracking (SCC) at ambient temperatures, the conditions known to promote ambient temperature TGSCC of austenitic stainless steel are reviewed. A mechanism that may give rise to TGSCC in limestone climbing anchors in warm marine environments is postulated.