基于小冲孔试验的2205双相不锈钢焊接接头的应力腐蚀开裂行为

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

在含有H^(+)的混合海水溶液中采用小冲孔应力腐蚀试验方法对2205双相不锈钢焊接接头不同区域的应力腐蚀开裂敏感性进行了研究。基于小冲孔试验的载荷-位移曲线建立了应力腐蚀开裂敏感性系数计算方法,并依托小冲孔试样毫微取样的优势对比了母材区、热影响区和焊缝区应力腐蚀敏感性的差异。从宏观断口与微观断口两方面分析了断裂机理。结果表明:焊缝区的应力腐蚀开裂敏感性均高于母材区和热影响区,焊缝区在海洋环境中更易发生应力腐蚀开裂。小冲孔应力腐蚀试验方法是一种评价焊接接头不同区域应力腐蚀开裂现象的有效方法。

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.