Bending characteristics and springback prediction for straightening of carbon steel-stainless steel bimetallic composite pipes

Abstract This paper focuses on carbon steel-stainless steel bimetallic composite pipes as the subject of investigation. By employing the theory of elastoplasticity, an analysis is conducted on the evolution of elastoplastic deformation across the cross-section of the composite pipe. Consequently, a formula delineating the moment-to-elastic-zone ratio segments under pressure straightening conditions for the composite pipe has been derived. The influence of varying ratios of pipe diameter and yield strength on the model is examined. Furthermore, three-point bending simulations were conducted by using ABAQUS CAE, and experiments were carried out under the same conditions by setting different compression amounts to obtain residual deflections. The deviation between simulation values and experimental values is very small, providing significant guidance. When the compression amount is within 4 mm, the error between theoretical values and experimental values does not exceed 0.199 mm.