An Investigation and Prediction of Springback of Sheet Metals under Cold Forming Condition

Low formability and springback especially at room temperature are known to be major obstacles to advancements in sheet metal forming industries. The integration of numerical simulation within the R&D activities of the automotive industries provides a significant development in overcoming these drawbacks. The aim of the present work is to model and predict the springback of a Galvanized low carbon steel automotive panel part. This part suffers from both positive and negative springback which physically measured using CMM. The objective is to determine the suitable forming process parameters that minimize and compensate the springback through robust FE model. The analysis of the springback was carried out following (Isotropic model and Yoshida – Uemori model) which are calibrated through cyclic stress strain curve. The material data of the Galvanized low carbon steel was implemented via lookup tables in the commercial finite element software Pam-Stamp^(TM). Firstly, the FE model was validated using the deformed part which suffers from springback problem at the same forming condition. The FE results were compared with the measured experimental trails providing very good agreement. Secondly, the validated FE model was used to determine the suitable forming parameters which could minimise the springback of the deformed part. (paper)