Stress corrosion behavior of pipeline steel(X52)welded joint

The resistance of pipeline steel joint welded by submerged arc welding to stress corrosion cracking (SCC) at its different regions in boiling mixed nitrate solution and in H_2S saturated solution at room temperature is examined by the constant-load tension method. The result shows that when tested in nitrate, the weld metal may be the weakest link of the joint if the welding material doesn't match well. The resistance to SCC of the joint in H_2S is very low, especially at the bond and coarse grain zone and is closely dependent on the metallurgical quality of base metal.     

高强钢焊接接头在H2S介质中的应力腐蚀性能

用恒载位伸法分别测定了ＨＧ８０钢焊接接头（焊态和回火态）各区在室温饱和Ｈ２Ｓ溶液中的应力腐蚀破裂（ＳＣＣ）抗力。试验结果表明，ＨＧ８０钢接头在介质中表现出很低的断裂抗力。其中焊缝金属是最薄弱的环节。对于焊接接头而言，不能简单地用硬度来预测或评价材料ＳＳＣＣ敏感性，用回火处理来提高高强钢接头的ＳＳＣＣ抗力时需要慎重对待关键在于这种处理能否消除敏感组织或有所改善。     

低碳钢焊接接头碱脆破裂的研究

本文叙述了用多种试验方法测试评定低碳钢焊接接头对碱脆破裂的敏感性。提出低碳钢焊接结构防止碱脆破裂的基本措施是消除焊后残留应力。     

铝厂低碳钢设备碱脆破裂的研究

铝厂碱脆破裂是最危险的破坏形式之一,本文采用了恒应变四点弯曲应力腐蚀试验、恒载荷拉伸试验、焊接接头圆盘试验以及恒载荷悬臂梁试验等几种常用的试验方法评估了20g低碳钢及其焊接接头对于碱脆破裂的敏感性,并在117℃、30%NaOH溶液中获得相应的试验数据。同时利用显微镜、扫描电镜及电化学方法探讨了碱脆破裂的机制。文中所获得的一些碱脆破坏试验结果及技术措施已在某些铝厂及化工厂获得一定的经济效果。