Effect of Cold and Hot Compounds Forming on Microstructures and Mechanical Properties in the Deformation Zone of Sharp-Edged High-Strength Steel Sections

We researched the cold and hot composite-forming process, setting the forming speed at 2 m/min, the induction heating frequency at 40 KHz, and the induction current at 3000 A, and manufactured curtain wall steel with sharp corners. We analyzed the microstructure and mechanical properties of the deformation zone of the sharp-edged section using a tensile test, impact test analysis, metallographic observation (OM), fracture morphology observation, and electron backscatter diffraction (EBSD) analysis. The results show that the formed profile had a 96% reduction in the radius of the outer fillet and a 76% increase in the thickness of the corner compared to the pre-formed shape. The tensile strength increased by 3.6%, and the elongation after break increased by 13%. A forming temperature of 850 °C and forming deformation of 70% were determined as the optimum process parameters.