Study on microstructures and properties of preheated flash butt welded SW400 steel joints

Under the spirit of sustainable development，‘lightweight’has been gradually included into the vehicle design criterion by many manufacturers and used in automobile production．Following this trend，domestic wheel suppliers also begin to study the technology of lightweight wheel．One way to achieve this goal is improving strength grade of the steel and optimizing the structure design in the field of steel wheels．But there are a few problems in flash butt welding process in the application of high strength steel，leading to high rejection rates．SW400 steel is a special high strength wheel steel developed by Benxi Steel．Taking SW400 steel as the research material，this article studys the feasibility of improving the properties of rim flash butt welded joints by adding preheating process．