摘要
研究了外加纵向磁场对SUS316L奥氏体不锈钢激光-稀有气体保护复合焊接接头成形特点、微观组织及显微硬度分布的影响。实验结果表明,在外加纵向磁场的作用下,接头的余高减小,熔宽增大,成形系数增大,截面宽而深。外加磁场改变了接头的热循环,使热影响区析出长条形δ-铁素体,抑制了晶粒的生长。外加磁场使熔池旋转,接头晶粒得到细化,结晶均匀性得到提高,显微硬度分布变得稳定。这种影响随着磁感应强度的增加而增强,随着接头深度的增大而减弱。
The influences of external longitudinal magnetic field on weld joint forming characteristics, microstructure and microhardness distribution are investigated in SUS316L austenitic stainless steels by laser-metal inert gas hybrid welding. The experimental results show that, under the action of external longitudinal magnetic field, the weld joint reinforcement decreases, the weld width increases, the forming coefficient increases, and the cross section appears wide and deep. The external magnetic field alters the thermal cycle of the weld joint, which makes the striped 6-ferrite precipitation occur in the heat affected zone and the grain growth is inhibited. The external magnetic field causes the rotation of the molten pool and the weld joint grains are refined. The uniformity of crystallization is improved and the microhardness distribution becomes stable. This effect enhances with the increase of the magnetic induction intensity but weakens with the increase of the weld joint depth.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2017年第8期139-147,共9页
Chinese Journal of Lasers
基金
国家973计划(2014CB045703)
