Study on Springback Forecast on Multi-Angular Bending
|School||South China University of Technology|
|Keywords||Springback Numerical Simulation Multi-angular bending Effecting factors|
The metal sheet bending is a kind of plastic processing methods, which is widely used in various fields. In the metal sheet forming process, the springback is an inevitable phenomenon, and it directly affects the precision of workpiece. Springback is a very complex issue, which concludes many factors coupled and shows a high degree of nonlinearity. At the same time, the problem becomes more difficult to grasp because of the complex conditions in the actual production. So, the springback has been an important factor, which restricted the mold design, manufacturing and product quality. Springbanck is that the residual stress makes the workpiece produce the elastic recovery, after the metal sheet forming, and then, the external force to remove the workpiece. The complete springback is a historical cumulative effect of the whole forming, including loading and unloading process. The rebound process is very complex and difficult to accurately control, because the degree of the springback is affected on many factors. It is great significance to study the problem of springback, as the existence of the resilience has been severely affected the part of dimensional accuracy , precision of form and position tolerances.The dissertation is to summarize the main factors influencing rebound and study the rules of the various factors on multi-angular bending and springing according to the problem of multi-angular bending and springing, through theoretical analysis on the stress distribution of the sheet metal bending and springback, using the method of numerical simulation computer simulation and combining experiments. The main research work is as follows:Firstly, the dissertation elaborates on the principle of the metal sheet bending and springback, analyses the process and characteristics on the metal sheet forming and springback and researches respectively the stress distribution and deformation in the deformation zone and non-deformation zone during Bending and Springback about the single angle part based on the theoretical knowledge, and then discussed the process of the multi-angular part bending and springback. The dissertation also explained the forms to express the springback angle and the factors to influence springback.Secondly, the dissertation simulates the process of the multi-angular part bending and springing, using hybrid simulation algorithm based on ABAQUS. The dissertation also studied the key technologies about numerical simulation and ultimately selected the suitable technical parameters, which is to prepare for further research.Thirdly, the dissertation designs and manufactures a set of molds according to the experimental needs. Through the method of orthogonal experiment, the paper obtains the primary and secondary order of the factors and gets the best parameters, with the four factors selected experimented, the springback angles measured and the datas studied with the method of a range analysis.Finally, the dissertation studies the simulation of the multi-angle piece and analyzes the factors which affects the springback and especially researches the various interactions between the bend angles. The dissertation also concludes the rules of the factors through studying the factors, which is significant to master the springback in the process of bending and springing.