Study Of Springback For Design Of The Tool In Big Sheet Metal Forming

Sheet metal stamping is an extremely important process for the manufacture of sheet metal parts and is widely used in automobile, aircraft, electronic instrument and other industries. Its required tool is called the mother of the industrial products, some industrial product relie on tool to produce on a large scale. Due to the enormous promoting effect to social production and national economy, the tool market of the world develops rapidly. With the development of the tool market, curved tool application has a more and more range.However, the problem of springback does not always have a fairly good solution, blocking the efficacy of the manufacture of curved tool. What is more, the research of large-scale sheet metal re-spring, such as the research of the automobile cover parts, becomes the tough problem. To resolve this actual problem, the paper proposes the method of compensating springback in the design of curved tool.In the study of springback, the influence of material parameters, die gap, lubrication, die radius, etc. on springback is analyzed, this paper pays attention to consider material parameters, such as material yield stress, thickness and target radius. Base on analysis of re-spring process of ideal elastic-plastic material, the paper proposes a calculating method for sheet metal bending and springback. Inverse solution of springback in bending, a formula to calculate the bending radius by material yield stress, thickness and target radius is derived. At the same time, the paper is helpful for tool modification in sheet metal forming.In the paper, a experience formula is led into. The paper compares formula with experience formula and analyses them. At the same time, a model is built. This model is analyzed in the simulated experiment in finite element method. Deducing formula is verified further, analyzed and amended, which makes it especially accurate. In the end, the project and practice is guided. By a train of analysis and demonstration, a conclusion can be reached: Compared with the experience formula, the inferring formula is especially accurate during the period of elastic-plastic, it has certain directive function about the project and practice.In addition, the paper briefly introduces the history, the current situation and the future development about the study of re-spring.