Author : Balaji.S.V., Karuppuswamy.P and Karuppusamy.S

Sheet metal forming is one of the most common metals forming process. The production with accuracy is an important factor in forming process in sheet metal industries. In variety of sheet metal forming process, the bending of sheet metal is major area in the sheet metal industry. The major causes for inconsistent sheet metal part in bending process is spring back, die clearance, tool radius and load of press. Here we have taken the experimental study of The 8 mm thick plate bending process in Fe 410W-C material. The bending process in the plate is an important application because; it is used in various engineering applications. The bending analysis of 8mm thick plate bending has been one of the important issues in theory and engineering. Spring back is a common phenomenon caused by the elastic redistribution of internal stresses during unloading in the bending process and it directly affects the precision and quality of products. So there are strong demands from the manufacturing industry for evaluating the amount of spring back and predicting the final geometry of the work piece with accuracy after the process. There are many bending methods used widely, but the three point bending has been utilized extensively for the bending process due to its apparent simplicity and good flexibility. In this paper, three point bending method is used for 8mm thick plate bending process. Since the prediction of this phenomenon and the compensating of spring back, during process are still a formidable challenge today, few efforts have already been devoted to this objective as experimental studies and theoretical analysis. Here real time experiments conducted with 8mm thick plate for 3 different radiuses. Nearly 10 experiments conducted for each radius and every parameter of experiments noted down. Numerical simulations using finite element analysis are also performed for these three different radii to investigate the effect of spring back and all relevant parameters which are available through simulation also noted down. The finite element model is validated with experimental results of spring back. Then taking the account of three different type tests of three different radius which are formed by our experiments, a well formed pieces without any defect, due to formation is taken and bending radii are measured. Then the optimization of spring back, die clearances for different bending radius done using neural networks in later stage.

Keywords: sheet metal forming; spring back; three point bending; finite element analysis; elastic redistribution of internal stresses, thick plate bending process.

Article published in International Conference on Advances in Mechanical Sciences 2014, Special Issue-2 (Feb 2014)