Stress Corrosion Cracking Behavior of 2205 Duplex Stainless Steel Welded Joint Based on Small Punch Test

Stress corrosion cracking (SCC) sensitivity of different regions of 2205 duplex stainless steel welded joint in seawater solution with different H⁺ concentrations was studied by small punch stress corrosion test. A calculation method of SCC sensitivity coefficient was established based on the load-displacement curves from small punch test. And the difference of SCC sensitivity in base metal zone, heat affected zone and weld zone was compared based on the advantage of small punch micro sample. The fracture mechanism was analyzed from both macroscopic and microscopic fracture. The results showed that the SCC sensitivity of weld zone was higher than that of base metal zone and heat affected zone, so the heat affected zone was prone to SCC in marine environment. Small punch stress corrosion test method is an effective method to evaluate stress corrosion cracking of different zones of welded joints.