厚壁焊件热影响区韧性沿厚度分布研究(上)  

Study on the Toughness Distribution of Heat Affected Zone of Welded Joints with Thick Walls in Thickness Direction (Ⅰ)

作　　者：胡梦佳[1] 蔡志鹏[1,2] 李克俭[1] 张宇[1] 潘际銮[1] 刘霞[1,3] 王朋 许晓进 丁玉明 霍鑫 HU Mengjia CAI Zhipeng LI Kejian ZHANG Yu PAN Jiluan LIU Xia WANG Peng XUXiaojin DING Yuming HUO Xin(Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China Collaborative Innovation Center of Advanced Nuclear Energy Technology, Beijing 100084, China Shanghai Electric Power Generation Equipment Co., Ltd. Turbine Plant, Shanghai 200240, China)

机构地区：[1]清华大学机械工程系,北京100084 [2]先进核能技术协同创新中心,北京100084 [3]上海电气电站设备有限公司汽轮机厂,上海200240

出　　处：《热力透平》2017年第2期98-102,共5页Thermal Turbine

摘　　要：采用夏比冲击实验和小冲杆实验对2.25Cr-1Mo-0.25V钢厚壁焊接接头热影响区韧性沿焊缝深度方向的分布进行了测试,并使用体视显微镜和扫描电镜对冲击断口进行观察,对裂纹扩展路径进行金相观察。结果表明,热影响区的冲击韧性和断裂韧性沿焊缝深度方向都表现出了"中部区域韧性优于两侧"的特征,冲击裂纹主要沿粗晶区扩展,推测韧性分布的差异有可能是由于不同位置的塑性应变不同造成的,即塑性损伤沿厚度方向的分布差异是导致韧性分布差异的原因。相关结果对评估厚壁焊接构件接头性能和改进制造工艺具有一定参考意义。Charpy impact test and small punch test were conducted to measure the toughness distributionalong the thickness direction in heat affected zone （HAZ） made of 2. 25Cr-1Mo-0. 25V steel. The stereomieroscope and scanning microscope were employed to investigate the facture appearance, and metallographic observation was applied for the crack propagation path. It was found that the toughness of HAZ in the central part was superior to that in the two sides along the direction of thickness. The crack extended mainly along the coarse grain zone. It＇s inferred that the plastic strain distribution should be responsible for the distribution of toughness in the HAZ along the thickness direction. All the results could provide important reference for evaluating the performance of the thick-wall welded joint and improving the manufacturing process.

关 键 词：韧性 塑性应变 夏比冲击实验 小冲杆实验 

分 类 号：TG407[金属学及工艺—焊接]