小口径G115新型马氏体耐热钢管接头组织性能分析
Microstructure and Mechanical Property Analysis of Small Diameter G115 New Martensitic Heat Resistant Steel Tube Welded Joint
章亚林 1王立玉 2王学 3张鹏 2黄桥生1
作者信息
- 1. 国家能源集团科学技术研究院有限公司,湖北 武汉 410066
- 2. 中国能源建设集团江苏省电力建设第一工程有限公司,江苏 南京 210001
- 3. 武汉大学动力与机械学院,湖北 武汉 430072
- 折叠
摘要
采用自主开发的焊材,对我国研制的G115 新型马氏体耐热钢进行了小口径管焊接工艺试验,分析了接头的显微组织,测试了接头的力学性能.结果表明,G115 小口径管的焊接工艺性良好,在常规GTAW工艺下焊接可以得到无缺陷的焊接接头,接头的常温拉伸和弯曲性能均满足相关要求.焊缝在焊态下的韧性很低,经过760℃×1.5 h的焊后热处理后,其冲击吸收能量由6J提高到80J以上.焊后热处理后,启裂区的断裂机制由解理转变为韧窝,明显提高了裂纹萌生需要的能量.G115 焊接接头仍然存在细晶热影响区(FGHAZ)和软化带,软化带出现在靠近母材的临界正火区.
Abstract
Using self-developed welding material,the welding procedure test was performed for small dimameter tube of new martensitic heat resistant steel G115 developed in China.The microstructure of the G115 welded joint was observed and its mechanical properties were tested.The results show that the welding process of the G115 small dimameter tube is good and the joint without defects can be obtained by conventional GTAW process.The room temperature tensile and bending properties of the joint meet the relevant requirements.The toughness of the weld seam in welded state is very low.After the postweld heat treatment(PWHT)at 760℃ for 1.5 h,its impact absorption energy increases from 6 J to more than 80 J.After PWHT,the fracture mode of the crack initiation area changes from cleavage to dimple,which increases the crack propagation energy.There are still fine grain heat-affected zone and softening zone in the joint,softening occurs in the intercritical heat-affected zone near the base metal.
关键词
G115钢/马氏体耐热钢/力学性能/显微组织Key words
G115 steel/martensitic heat resistant steel/mechanical properties/microstructure引用本文复制引用
出版年
2024
NETL
NSTL
万方数据