兆瓦级风电后机架用Q345C/D结构钢低温冲击性能研究  

Research on Low Temperature Impact Properties of Q345C/D Steels for Rear Frame of Megawatt Wind Turbine

作　　者：李沛海 高鹏宇 邓杰 邓薇薇 LI Peihai;GAO Pengyu;DENG Jie;DENG Weiwei(Chongqing ChangZheng Heavy Industry Co.,Ltd.,Chongqing 400083,China)

机构地区：[1]重庆长征重工有限责任公司,重庆400083

出　　处：《热加工工艺》2020年第23期129-133,共5页Hot Working Technology

摘　　要：为验证Q345C/D焊接接头的低温冲击性能能否满足兆瓦级风电后机架材料使用要求,研究了热处理前后Q345C/D焊接接头在-20、-30、-40℃的低温冲击性能。实验表明,热处理前后Q345C焊接接头-40℃下平均冲击功分别为53 J和92 J,热处理前后Q345D焊接接头在-40℃下平均冲击功分别为97.3 J和138.6 J。经过热处理后,合金元素碳化物析出,形成了沉淀强化,并且焊接内应力降低,接头低温冲击韧性得到了明显改善。冲击断口SEM照片说明热处理前后的Q345C/D焊接接头均为韧性断裂。In order to verify whether the impact performance of Q345C/D welded joints at low temperature is suitable for the requirement of frame of a megawatt wind turbine, the low temperature impact properties of Q345C/D welded joints before and after heat treatment at-20℃,-30℃, and-40℃ were investigated. The experiment proves that the average impact energy of Q345C welded joints at-40℃ before and after heat treatment is 53 J and 92 J respectively. The average impact energy of Q345D welded joints at-40℃ before and after heat treatment is 97.3 J and 138.6 J respectively. After heat treatment, the carbide precipitates, the precipitation strengthening forms and the welding stress decreases. The low temperature impact toughness of the joint improves significantly. The SEM images of impact fracture indicate that the Q345C/D weld joint before and after heat treatment is ductile fracture.

关 键 词：低温冲击性能 风电机架 焊接接头 Q345C/D结构钢 

分 类 号：TG457.11[金属学及工艺—焊接]