Reasearch Of Laser Welding Process Of Stainless Steel Train Body

The increasing shortage of global resources raise pressing requirement of lesslightweight of the train body.With the enough strength and corrosion resistance,it willgreatly reduce the quality of the train body bu using the SUS301L trainless steel toproduce.And the fiber laser has successes applied on the industrial,especially cooperationwith the Robert an improve the production efficiency.This paper focuses on the researchof application of laser welding technology on stainless steel train body manufacture,anddemonstrate the feasibility of laser welding technology applied in the manufacture of thetrain body.Process test and property test of three typical joints has been done：By welding one side of the fillet joint of SUS301L-HT stainless steel sheet(1mm),thethree sides welding forning are good.And the deformation of fillet joint is little.The tensile strength of laser butt joint of SUS301L stainless steel sheet(4mm) is99%of the base mental.In the bend test,the welding appears no defects after the sample wasbended180°.And the intergranular corrosion resistance of the weld is good.The surface of the non-penetration sheet(2mm) of the lap joint which is composed ofSUS30L-HT(1mm)sheet and SUS301L-DLT(2mm)sheet is nice.According to the standardof EN15085-3,the strength of a20mm long laser lap weld is equivalent to one spot ofthe resistance welding.In the condition of1×107cycles,the fatigue of the butt joint of SUS301L-DLTsheet(2mm) is310MPa which is slightly lower than the base mental330MPa but muchhigher than the MIG weld.The process parameters are optimized through the unit welding test.At last we weldedthe doorframe and the side wall which are the main part of the train body by the Robert-Laser welding system.The productions meet all the indicators are successfullyinstalled in the train body.Therefore It’s feasible tha applying the laser welding on themanufacture of the stainless steel train body.