采用工艺试验,力学性能试验以及光镜、电镜等显微分析等方法对转向架构架焊接接头的组织形态和力学性能进行了研究,确定了焊接接头各区的组织形态和力学性能的变化情况。研究结果表明,利用(Ar+CO2)混合气体保护焊焊接Q345E钢时,焊缝组织主要为先共析体素体、针状铁素体和珠光体,热影响区组织主要为先共析铁素体、珠光体和粒状贝氏体,焊接接头具有良好的力学性能。

The microstructure and mechanical properties of the welding joints of bogie frame were studied through mechanical tests,optical and electron microscope observations as well as electron probe analysis etc.,then the microstructure state and variation of mechanical properties were determined. The results showed that the welded seam gotten from (Ar+CO2) gas shielded arc welding mainly contains proeutectoid ferrite,acicular ferrite and pearlite,while the heat-affected zone of which mainly contains proeutectoid ferrite,perlite and granular bainite. Tensile and impact tests combined with the hardness measurements demonstrated that the corresponding welded joints have favorable mechanical properties.