A novel approach to springback control of high-strength steel in cold roll forming

To high-precision control the springback of high-strength steel (HSS) in cold roll forming, the 3D finite element analysis (FEA) models of hat-shaped sectional HSS roll forming process were built with the professional roll forming software COPRA. Two conventional angle adjusting methods for HSS, i.e., the Namaste-type and the Platform-type applied widely for complex-sectional normal steel, easily lead to the edge waves and asymmetric behavior, respectively, especially high springback that is difficult to control by the FEA simulation and practical production of HSS cold roll forming process. The roll design of the UDT (USTB-Durable T)-type angle adjusting method was developed to significantly reduce springback with the improvement of the edge waves and asymmetric behavior in the hat-shaped sectional HSS roll forming process by the FEA simulation. The proposed angle compensation method based on UDT-type angle adjusting method achieved high-precision springback control by the FEA simulation, which provides a novel approach for springback control effectively in complex-sectional HSS roll forming process. The industrial application gives remarkable results that the hat-shaped sectional HSS product can strictly meet market requirements of less than 0.5° by the proposed angle compensation method based on UDT-type angle adjusting method.