摘要
采用ERNiCr-3和ERNiCrMo-3两种镍基焊丝,GTAW法实现T92/TP347H异种钢管焊接。研究了接头的显微组织结构、熔合区(线)两侧的成分分布和接头的力学性能,以及焊后热处理对接头组织结构及力学性能影响等。结果表明:T92/TP347H异种钢接头T92侧热影响区(HAZ)主要由过热区、粗晶区及细晶区构成;TP347H侧HAZ没有明显晶粒长大的现象,但晶界、晶内有碳化物析出。两种焊丝焊接的T92/TP347H异种钢接头拉伸断裂面位于TP347H侧母材,焊缝强度较高;ERNiCrMo-3焊接接头的强度高于ERNiCr-3焊接接头,但塑、韧性不如后者。750℃,30 min焊后热处理,有助于降低T92侧HAZ硬度,改善接头的综合力学性能。
T92/TP347H dissimilar steel joints were welded through the GTAW techlonogy,using two type of Ni-based welding wires ERNiCr-3 and ERNiCrMo-3.Microstructures and mechanical properties of the T92/TP347H dissimilar steel welded joints were studied.Effects of the post-weld heat-treatment on the microstructures and mechanical properties of the joints were also investigated.The results show that in the T92/TP347H dissimilar steel welded joints,the T92 heat effected zone（HAZ） mainly consists of the superheated zone,coarse grain zone and fine grain zone.The grain growth of the HAZ of TP347H is not found,nevertheless,the cabrides precipitating along the grain boundaries and inside the grains was detected.Tensile fracture of the joints always takes place in the base metal of TP347H for these two Ni-based welded joints,it indicates the higher tensile strength from two welding seams.Moreover,the ERNiCrMo-3 welded joints are of higher tensile strength,lower plasticities and inpact toughnesses,comparing with the ERNiCr-3 welded ones.The post-weld heat-treatment can improve the comprehensive mechanical properties of these two T92/TP347H dissimilar steel welded joints through reducing the handness value of the T92 HAZ.
出处
《压力容器》
北大核心
2010年第12期1-7,共7页
Pressure Vessel Technology
基金
安徽省电力科学研究院技术开发基金(2009咨-JS-03)
