Resistance to Stress Corrosion Cracking

One of the chief attributes of the nickel alloys is their resistance to chloride-induced stress corrosion cracking. A common solution for assessing the resistance of materials to this extremely destructive form of attack is boiling 45% magnesium chloride (ASTM Standard G 36), typically with stressed U-bend samples. As is evident from the following results, the three nickel alloys (C-22®, C-276 and 625) are much more resistant to this form of attack than the comparative, austenitic stainless steels. The tests were stopped after 1,008 hours (six weeks).

Alloy Time to Cracking
316L 2 h
254SMO 24 h
625 No Cracking in 1,008 h
C-276 No Cracking in 1,008 h
C-22® No Cracking in 1,008 h