| Automobile industry always focus on reducing the weight of vehicle body.Improving the formability of automobile steel plate as well as enhancing the automobile collision performance and safety coefficient of automobile operation.High strength and high plasticity steel plate is an important way to realize the lightweight of automobile.TWIP steel developed by Twinning Induced Plasticity(TWIP),which has high strength and good plasticity,shows a wide application prospect in the process of automobile lightweighting.Though TWIP steel has good formability,its rebound in stamping process is very serious,which tremendously hindered its application.With the development of the automobile industry,in recent years,the demand for accuracy of parts forming and which made the springback problem become more serious.There are many factors that affect the springback of TWIP steel,such as: blank holder force,friction coefficient,thickness of sheet metal,fillet radius,bending angle,mold clearance and so on.The springback is affected by many factors,which makes its prediction and control in TWIP steel forming process becomes very difficult.The rebound defect is one of the hardest thing to overcome in high strength steel forming process.Traditionally,the control of springback defects is mainly on the workpiece to keep the test mode and repair mode,which is inefficient and time-consuming.In this paper,the springback of U-shaped parts is studied by using the numerical simulation method in the springback of TWIP steel,and the optimized parameters are optimized by robust optimization method.Excellent combination of process parameters,effective control of the rebound.The research results have important guiding function on the stamping process and mold design of TWIP steel,which has a positive effect on the application of TWIP steel. |
