Research On Incremental Sheet Forming Process Of Car Covering Parts

Forming process of metal sheet is widely used in the manufacturing industry,but the traditional forming process of metal sheet is formed by the mold.The traditional forming process has the advantages of accurate and fast,but the die manufacturing cycle is long,and the flexibility of forming process is low.Therefore, it is not suitable for producing small batch parts.In order to solve these problems,various kinds of sheet forming processes without die have been studied by scholars in different countries.The incremental sheet forming(ISF) process is one of the most promising technologies in these forming process.ISF is applied the layered manufacturing to the forming of sheet.ISF make the digital manufacture of parts come true and has a high flexibility.In this paper, we take the car body covering parts as the research object,and the finite element simulation analysis is carried out on the ISF of parts.The stress field, strain field and thickness distribution of ISF's parts with different process parameters are simulated.The simulation results show that the stress of parts is less than the tensile strength of the material,the deformation of parts is not very severe.Through the analysis of simulation, we think the crack of parts will not appear in the forming process.The results of simulation show that the experiment of ISF is feasible.So in this paper,we set up four groups of experiments, through experiments to study the effect of process parameters on the forming results.The results of the experiments show that the value of the step depth needs to be determined according to the shape of the parts.When the slope of the part is small, it is needed to reduce the step depth to obtain a higher forming quality.Two sides clamping method can shorten the processing time, and save the sheet,but the thinning and springback of parts is more severe,and may cause some defects.Therefore,the use of four sides clamping method will make the forming results be more good.The thinning of parts is a key point in the analysis of the results of ISF.This is because ISF is a process of drawing, the thinning of parts reflects the deformation of parts.The thickness distribution of the parts shows that the area of serious thinning is just in the larger slope area of parts.The result is in agreement with the sine law.So the thinning of parts can be estimated by the sine law.When the thinning of parts is very severe,we try to use multi-stage incremental sheet forming to solve this problem.