Study On Corrosion Of S355J2W Weathering Steel Welded Joints

With the rapid development of railway transport, railway vehicle used in the manufacture increasingly high performance requirements of materials,especially corrosion.Thus,with good resistance to atmospheric corrosion of weathering steel is widely used. Welding of railway vehicles is the main connection process,and the stress concentration is the corrosion of welded joints are often the most serious of the problem is most likely the location of fracture.Corrosion resistance of welded joints are directly affected by the use of weathering steel performance. Bogie's side of CRH3 were entirely used S355J2W weathering steel materials which dependent on imports. S355J2W weathering steel is Germany's newly developed new type of weathering steel,it is not yet found in terms of its corrosion and welding related information,often encountered in the production of S355J2W weathering steel welding issues. Hence we need a study on microstructure and properties of S355J2W weathering steel welded joint.To study the performance of welded joints S355J2W,we choose the gas shielded arc welding S355J2W weathering steel in this subject,and some of these samples were annealed after welding,the material of annealing is to study the corrosion and other mechanical properties,and explore the S355J2W weathering steel is in the welding process of what happened,and the mechanism of microstructure changes produced,and final analysis if have welding defects in the process and what factors infect of welded joints performance,then we can understanding the welding technology of S355J2W weathering steel.In order to better guide S355J2W weathering steel welding technology to provide theoretical basis,This article uses immersion experimental study on the corrosion mechanism and the regularity and observation of morphology of embroidery, analysis of corrosion and mechanical property requirements in use can be met,and to stretch the welded joints,general mechanical properties such as impact testing.While comparative corrosion before and after the performance, analysis of microstructure and fracture morphology.morphology for ductile fracture,3-4 times higher than the standard value.Obtained through experimental analysis either annealed or annealed state of welding joint in the state of the corrosion resistance of materials,they are much better than air cooled State, trains can run to safety.