高速列车转向架SMA490BW耐候钢焊接热影响区模拟试验

摘要

实验分析高速列车转向架构架用钢焊接接头热影响区的组织性能.采用Gleeble-3500热模拟试验机对SMA490BW耐候结构钢进行焊接时温度循环的模拟,研究了三种焊接线能量状态下两个不同特征热影响区的组织和性能,为焊接工艺的优化提供理论依据.SMA490BW耐候钢的过热温度区间热影响区组织多为贝氏体,并且组织性能根据采用线能量的不同会产生明显差异.随着焊接热输入的增加,其组织晶粒增大,强韧性下降.推荐热输入线能量E=5 kJ/cm.%this paper analyzed the microstructures and mechanical properties of welding heat affected zone in bogie frame of the high speed railway.The experiment of welding thermal cycle was carried out for corrosion resistant steel for welded structure SMA 490BW by means of Gleeble-3500 thermal simulator.Studied the microstructures and mechanical properties of two different HAZ in the 3 kinds of heat input conditions.For providing a theoretical basis to the optimization of the welding process.The microstructure of overheating temperature range heat affected zone is bainites mostly;the mechanical properties of the steel would change clearly along with the different heat inputs.With the increase of heat input,the grain increased,strength and toughness decreased.Heat input E=5 kJ/cm as recommended.