Effect of Welding Procedures on Microstructure and Mechanical Properties of Flash Butt Welded Joints for B600CL Steel
By flash welding method,the 4.5mm thickness B600 CL hot rolling steel plates were welded with different welding parameters.The microstructure of interface region was observed,and the tensile properties of the welded joints were researched,the effects of upset pressure,upset allowance and flash allowance on the microstructure and mechanical properties of welded joints were studied.The results show that,with the increase of upset pressure,the bainite structure in interface refines,while the tensile strength and elongation of the weld joint are affected slightly;with the increase of upset allowance,the microstructure gradually coarsens,the tensile strength and elongation decreases,and the tensile properties deteriorate when the upset allowance is over 5.5mm.With the increase of flash allowance,the bainite structure in interface gradually coarsens,and the tensile strength and elongation gradually reduce;when the flash allowance is more than 10 mm,the tensile properties are seriously deteriorated.