焊接工艺对8mm厚SS400超细晶钢焊接组织影响

Effect of Welding Process on Microstructure of Welded Joint of SS400 Steel with 8 mm Thickness

为了得到焊接工艺对8 mm厚SS400超细晶粒钢焊接接头显微组织的影响,分别采用不同焊材和焊接参数对8 mm厚SS400钢板进行了焊接试验,并对接头显微组织进行了观察和分析。试验结果表明,焊条对焊缝组织影响较大,对热影响区组织影响很小,当采用J507碱性焊条焊接时,焊缝可以得到较多的针状铁素体。焊接道次和焊接热输入对焊接热影响区组织影响较大,当采用J422酸性焊条两道次,热输入由11.6 kJ/cm增大到14.9 kJ/cm进行焊接时,热影响区晶粒尺寸和组织分布较为理想。当采用J507碱性焊条单道次,热输入由10.6 kJ/cm增大到19.9 kJ/cm焊接时,热影响区组织较为粗大且分布不均匀。在实际生产中,考虑焊接质量和焊接效率时,J422酸性焊条和热输入为14.9kJ/cm为最优焊接工艺参数。

In order to get the influence of welding process on the microstmcture of welded joint of 8mm thick SS400 steel plate, the welding tests under different welding rods and welding process parameters were carried out on SS400 steel with 8mm thick plates and the joint microstructure was observed. The experimental results show that the effect of welding rods on the mierostmcture of the weld is greater, and the impact on the microstmcture of heat affected zone was less. Elected with J507 basic electrode, the weld microstmeture is large acicular ferrite. The effect of welding heat input and welding pass on heat affected zone is greater. When the heat input from 11.6 kJ/cm increases to 14.9 kJ/em and using J422 two-pass,HAZ grain size and tissue distribution is more desirable. When the heat input from the 10.6 kJ/cm increasing to 19.9 kJ/cm and using J507 single-pass, HAZ is more coarse and uneven distribution. In actual production, considering the efficiency and quality of welding, J422 acid electrode and the heat input 14.9 kJ/cm are optimal welding parameters.