304不锈钢焊接接头的耐应力腐蚀性能

Stress Corrosion Behavior of 304 Welding Joints of Stainless Steel Tube

碳钢／304不锈钢复合管如果不锈钢钢管的焊接工艺参数不当，焊接接头便容易发生应力腐蚀。采用钨极氩弧焊方法焊接了304不锈钢钢管，通过慢应变速率拉伸和双环动电位再活化试验研究了不同焊接工艺参数焊接接头的耐应力腐蚀性能。结果表明，可有效提高耐应力腐蚀性能的最优焊接工艺：氩气流量为12～15L／min，焊丝为ER308，焊接电压为50V，电流为50A，焊接速度为8～10cm／min；选择合适的焊丝和降低焊接电流可有效增加304不锈钢焊接接头处的耐应力腐蚀性能。

The welding joints of carbon steel /304 stainless steel composite tubes will be liable to stress corrosion if improper welding parameters are adopted for the stainless steel tube. Thus W electrode Ar-arc welding technique was applied to weld the stainless steel tube; and the stress corrosion behavior of the welding joints obtained under different welding parameters was investigated with slow strain rate drawing test and double-loop electrochemical potentiokinetic reactivation test. The best welding parameters were determined to be Ar flow rate of 12 ~ 15 L / min,welding wire of ER308,welding voltage of 50 V,welding current of 50 A,and welding speed of 8 ~ 10 cm / min. The welding joints obtained under the optimal welding parameters exhibitted excellent stress corrosion resistance. Moreover,it was feasible to effectively improve the stress corrosion resistance of the stainless steel tube welding joints by selecting proper welding wire and decreasing welding current.