E2209双相不锈钢焊条熔敷金属应力腐蚀研究

Investigation of Stress Corrosion Cracks in E2209 Duplex Stainless Steel Welding Joints

研究了2205双相不锈钢母材和E2209熔敷金属在空气、3. 5%NaCl中,应变速率为10^(-6) s^(-1)的慢拉伸应力腐蚀。用金相显微镜观察了母材和熔敷金属组织,通过扫描电镜对母材和E2209熔敷金属断口的形貌进行分析。实验结果表明:2205双相不锈钢母材和E2209熔敷金属的屈服强度差别不大,熔敷金属的塑性比低于母材;在3. 5%NaCl溶液中,母材的强度和塑性均无明显变化,熔敷金属的抗拉伸强度虽也无明显变化但其脆性明显增加,2205双相不锈钢母材和E2209熔敷金属的应力腐蚀敏感性指数分别为8. 82%和41. 56%。

The stress crack corrosion（SCC）of 2205 duplex stainless steel base material and E2209 welding joints wasstudied in air, 3. 5% NaCl solution at 10-6s-1slow tensile experiments. The microstructure of 2205 duplex stainless steeland E2209 welding joints was observed by metallographic microscope and fracture surface morphology was analyzed byscanning electron microscopy （SEM）. The experimental results showed that the base material and the weld joints of 2205duplex stainless steel had the same yield strength, and plasticity of 2205 duplex stainless steel weld joints was poor thanthat of base metal. In 3. 5% NaCl solution, the 2205 duplex stainless steel base material was nearly same in both yieldstrength and plasticity, the yield strength of welding joints did not change but the brittleness increased. The stresscorrosion susceptibility index of 2205 duplex stainless base steel material and the welding joints were 8. 82% and41. 56%.