9Ni钢板及焊接接头低温韧性研究

Study on Low Temperature Toughness of 9Ni Steel Plate and Welded Joint

以30mm厚度规格9Ni钢板及其焊接接头为研究对象,通过拉伸、低温冲击、弯曲、扫描电镜观察、CTOD等试验手段对母材、焊缝的低温韧性进行研究、分析。结果表明:9Ni钢板焊接接头硬度在150-320 HV(10)之间,焊缝冷裂纹敏感性较低;9Ni钢板及焊缝低温韧性良好,-196℃及-163℃低温冲击吸收能量≥100J;-163℃条件下母材及焊缝的CTOD值≥0.38mm;焊缝组织以奥氏体组织为主。

Taking the 30mm thick 9Ni steel plate and its welded joint as the research object,the low tempera-ture toughness of the base metal and welding seam is studied and analyzed by means?of?test such as tensile,low temperature impact,bending and scanning electron microscope observation,CTOD.The results show that the hardness of 9Ni steel plate welded joint is between 150-320 HV(10),and the weld cold crack sensitivity is low;9Ni steel plate and weld have good low-temperature toughness,and the low-temperature impact absorbed energy at-196℃and-163℃is≥100J;CTOD value of base metal and weld at-163℃is≥0.38mm;The weld mi-crostructure is mainly austenitic.