Q345B钢等离子-MAG复合焊接头组织与力学性能  

Microstructure and Mechanical Properties of Plasma-MAG Hybrid Welded Joints for Q345B Steel

作　　者：郭阳阳[1] 孙彦文[1] 霍海龙[1] 刘正[1] 郭雨菲 潘厚宏[1] 

机构地区：[1]西南交通大学材料科学与工程学院,成都四川610031

出　　处：《热加工工艺》2016年第11期215-217,共3页Hot Working Technology

基　　金：江苏科技大学先进焊接技术省级重点实验室开放研究基金资助项目(JSAWT-11-02)

摘　　要：以10 mm的Q345B钢板为母材,开Y型坡口,使用等离子-MAG复合焊方法,进行单层单道焊接。对焊接接头进行无损检测,未发现裂纹、气孔、夹渣等缺陷。分析焊接接头的显微组织,焊缝区主要由铁素体和珠光体构成,先共析铁素体沿柱状晶界析出,晶内主要是针状铁素体和珠光体的混合物;焊接热影响区较窄,组织形态变化明显但晶粒尺寸有所改善。硬度试验显示,焊缝和热影响区的硬度高于母材。对焊接接头进行拉伸、弯曲和冲击等力学性能测试,结果表明,采用等离子-MAG复合焊接方法得到的接头强度和韧塑性良好。The Q345 B steel with thickness of 10 mm and Y-groove was single layer welded by Plasma-MAG hybrid welding. Through non-destructive detection in the welding joint, no defects such as crack, pore and slag mclusion could be found. Microstructure of welding joint was also analyzed. The results show that the weld zone is mainly composed of ferrite and pearlite. Pre-eutectoid ferrite is formed along the grain boundary,and grain interior is mainly the mixture of acicular ferrite and pearlite. Moreover, the area of heat affected zone is narrow, and microstructure morphology changes significantly with the fine grain size. Hardness test shows that the hardness of the weld zone and heat affected zone is higher than that of the base metal. Mechanical properties of the welding joint, such as tensile, bending and impact absorption power were determined. The results show that the strength and toughness performance of the joint welded by Plasma-MAG hybrid welding are satisfied.

关 键 词：Q345B钢 等离子-MAG复合焊 焊缝组织 力学性能 

分 类 号：TG456.2[金属学及工艺—焊接]