The Simulation Of Composite Fine-blanking Process And The Optimization Of The Die Structure

Fine blanking is an advanced precision processing technology. The finished part has smooth edge and high quality. Because of high-efficient, low consumption, fine-quality and some other characteristics, fine-blanking has been widely used in industrial production. Composite fine-blanking, which is a new area of fine-blanking technology, can make a complex 3D part in only one stoke. But when blanking the thick stuff, the life of the die may be very short and the quality of the part may not meet the requirement, including the quality of punching section, the size and the shape of part. All of these have affected the promotion and application of this processing technology. In order to find the causes of these problems, it is needed to do the finite element analysis of composite fine-blanking process.Targets of this study are a kind of fine-blanking parts and the processing die. Actually this part is a ratchet wheel, which is used in cars. The structure of the part is very complicated, which has characteristics of semi-punching, chamfering and 3D tooth.In this thesis, first the 3D models of the die and part were created. Then these models were imported to the Deform 3D V5.0 software and the dynamic simulation of composite fine-blanking process was done with them. After the simulation , many results can be got,such as the processing animation of the forming part, the stress and strain of anywhere on or inside the part, the load curve of the main punch, and so on. These results can not only help us to confirm the force of the main punch which worked as both the blanking male die and extrusion female die,but also evaluate the quality of part and improve processing technology.In the following, the safety analysis and life prediction of the main punch was done, which is one of the most critical parts of the die. The tool used in the simulation is the Fatigue Analysis Module of Ansys Workbench 10.0. After that,first a proper result was got which included the stress and deformation of the main punch. And then the life of the main punch predicted from the simulation is very close to the actual production. On the other hand, through the simulation, the causes of the damage of the main punch were identified exactly. At the end, according to the problems of the main punch and the other parts which have direct relationship with it, an optimization project of the die structure was put forward. The project was adding one blank holder insert to protect it. This project has currently been affirmed and praised by our cooperative enterprises, which is supposed to be effective to solve these problems and lower the manufacture costs in the actual production.