贝氏体钢辙叉与U71Mn钢轨的焊接

采用 Gleeble 热模拟试验技术,确定贝氏体辙叉钢与 U71Mn 钢轨钢电阻对焊时热影响区的温度场分布及顶锻压力工艺参数;利用该参数在小型闪光焊机上进行小试件焊接试验,确定闪光焊接试验参数;利用 Gaas-100 次级直流闪光焊机对贝氏体钢辙叉与 U71Mn 钢轨进行整轨实际焊接,分析焊接接头拉伸、冲击、硬度分布等力学性能以及其组织结构.结果表明,贝氏体辙叉与钢轨闪光焊接的最佳顶锻压力为 30 MPa 左右,其焊接热影响区很小,焊接接头各项力学性能均达到了铁道部有关标准要求,贝氏体钢辙叉与 U71Mn 钢轨采用闪光对焊直接焊接是可行的.

Abstract：

The temperature field distribution of heat-affected zone (HAZ) in weld joints of bainite steel and U71Mn steel and the technical parameters of upset pressure of flash butt welding were determined by using the Gleeble thermal simulation test technology.After some small specimens of bainitic crossing steel and U71Mn rail steel were welded with a miniature flash butt welder by using the results of the parameters to determine the technical parameters of flash butt welding experiment, bainitic steel crossing and U71Mn steel rail were practically welded with Gaas-100 direct current flash butt welder. The mechanical properties, including tensile toughness, impact test and hardness,and the microstructure of welded joints were analyzed. The results show that the best upset pressure of flash butt welding is about 30 MPa, which the HAZ is very small, and the mechanical properties of the welded joint comes up to the standard of the Ministry of Railway. The welding bainitic crossing steel and U71Mn rail steel by flash butt welding is completely feasible.

Flash butt welding of bainite steel crossing with U71Mn steel rail

The temperature field distribution of heat-affected zone (HAZ) in weld joints of bainite steel and U71Mn steel and the technical parameters of upset pressure of flash butt welding were determined by using the Gleeble thermal simulation test technology.After some small specimens of bainitic crossing steel and U71Mn rail steel were welded with a miniature flash butt welder by using the results of the parameters to determine the technical parameters of flash butt welding experiment, bainitic steel crossing and U71Mn steel rail were practically welded with Gaas-100 direct current flash butt welder. The mechanical properties, including tensile toughness, impact test and hardness,and the microstructure of welded joints were analyzed. The results show that the best upset pressure of flash butt welding is about 30 MPa, which the HAZ is very small, and the mechanical properties of the welded joint comes up to the standard of the Ministry of Railway. The welding bainitic crossing steel and U71Mn rail steel by flash butt welding is completely feasible.