电焊机2025，Vol.55Issue(6)：155-162,8.DOI:10.7512/j.issn.1001-2303.2025.06.21
超超临界机组G115耐热钢管TIP TIG接头组织与性能研究
Study on the Microstructures and Properties of TIP TIG Joints of Ultra-Supercritical Unit G115 Heat-resistant Steel Pipe
摘要
Abstract
The TIG backing+TIP TIG welding method was used to connect G115 steel pipes of Φ530×115mm in power plant boilers,and a high-temperature tempering treatment was carried out at 770℃.The microstructure and mechanical properties of the joint were analyzed using metallographic,hardness,impact,and electrochemical corrosion testing methods.The research shows that the weld bead area is mainly composed of martensite and a small amount of ferrite,with the struc-ture being mainly equiaxed and columnar crystals;the heat-affected zone is mainly composed of plate martensite and some original austenite structures;the parent material presents a needle-like martensite morphology.The hardness of the joint shows a trend of first decreasing and then increasing,with the lowest at the parent material(210.5 HV0.2),the heat-affected zone slightly higher than the parent material zone,the hardness of the fusion zone first decreasing and then gradually increas-ing,and the highest hardness in the weld bead zone being about 281.3 HV0.2.The impact toughness shows the opposite trend,with the impact absorption work of the heat-affected zone reaching 103.09 J,significantly better than the 59.37 J of the weld bead zone,but both meet engineering requirements.Electrochemical corrosion tests reveal that the parent material has the best corrosion resistance,while the weld bead area has reduced corrosion resistance due to the high-hardness martensite structure.The research indicates that the TIP TIG welding process can achieve high-quality connections of G115 heat-resistant steel pipes,but the high hardness and low toughness characteristics of the weld bead area need to be further im-proved through process optimization(such as heat input control or alloy composition design)to enhance the comprehensive service performance of the joint.关键词
G115耐热钢管/TIP TIG焊/显微组织/力学性能/腐蚀Key words
G115 heat-resistant steel pipe/TIP TIG welding/microstructures/mechanical properties/corrosion分类
金属材料引用本文复制引用
盛美芳,刘鹏,郭新芳,杨刘波..超超临界机组G115耐热钢管TIP TIG接头组织与性能研究[J].电焊机,2025,55(6):155-162,8.基金项目
山东省自然科学基金(ZR2016JL017) （ZR2016JL017）
