针对槽型轨在服役过程中会出现磨损、疲劳等需要在现场维修的问题,选用特殊焊丝和特制的自动化焊补修复设备,在槽型轨失效单层堆焊正交试验探索最优堆焊工艺参数的基础上,探讨了多层焊补维修工艺的可行性,以及堆焊层组织和性能水平。结果表明:在预热300℃条件下,单层焊补层热影响区不可避免地出现了马氏体组织,在焊接电压31 V、送丝速度220 mm/s、焊接速度8 mm/s的条件下,堆焊层热影响区马氏体组织含量最少;多层焊补层热影响区组织均为珠光体,堆焊层无裂纹、气孔等缺陷,焊缝成形良好,焊缝组织为奥氏体,其硬度值与母材匹配良好,具有良好的工艺可行性。
Due to the problems that the groove rails need to be repaired in the field during the service process such as wear and fatigue,special welding wire and special automatic welding repair equipment are selected. On the basis of the optimal surfacing welding process parameters explored by the failed orthogonal test of the single-layer surfacing welding,discussing the feasibility of multi-layer welding repair process,and the organization and performance level of surfacing layer. The results show that under the preheating condition of300 ℃,in the heat affected zone of the single-layer welding layer,martensite is inevitable. But with the welding voltage of 31 V,wire feed speed of 220 mm/s,and welding speed of 8 mm/s,the martensite content in the heat-affected zone of the surfacing layer is the lowest. The microstructure of the heat affected zone in these multi-layers are pearlite,and there are no cracks,pores,and other defects in these layers. Welds are well-formed,the microstructure of welds are austenite,and their hardness values are well matched to the parent metal;the polymer damping material properties are not obviously effected by heat generated by welding repair process.Therefore,multi-layer welding repair technology has good process feasibility.
槽型轨服役损伤现场焊补维修技术
groove railservice damageonline weldingrepairing technology
相关文章
相关作者
相关机构