High quality automobile stamping parts should have high quality design method

2020-04-14 15:57:26

Automobile stamping parts should have good optimization design methods, so stamping manufacturers take stamping optimization design as an important way to reduce the cost of automobile manufacturing, which can make the appearance of automobile beautiful. The air resistance is reduced, the number of stamping parts and solder joints are reduced, and the cost is effectively reduced.

Empirical methods. This method is mainly based on some empirical calculation formulas, so its application scope is affected. It is mainly applied to the developable stamping parts with simple shapes (such as rotating parts, bending parts, or stamping parts composed of these simple shapes). Generally speaking, the method of developing the free-form surface of plate parts by experience belongs to the method of adaptability. Its accuracy is affected by many factors such as the user's experience, the empirical formula used and the selection of specific process parameters. Its accuracy needs to be further improved.

The basic assumption of slip line method is that the thickness of sheet metal flange is constant, and it is in plane strain state, the material is isotropic, no hardening, and the effect of friction distribution on plastic flow is not considered.

According to the description of the slip line method, only the stamping parts with relatively simple shape can establish the corresponding slip line field. And only under the very simple boundary condition can the mathematical expression of the slip line be given from the solution of the characteristic square. In general, it is necessary to use the numerical integration of the characteristic equation to obtain the approximate slip line field according to the given boundary conditions and point by point recurrence. This method is based on the transformation of the differential equation of the characteristic line as the finite difference relation and the characteristics of the slip line as the basis. Therefore, the slip line method is difficult to be applied in practical production because of its complicated mathematical operation.

Geometric mapping. They think that the mapping from workpiece to billet can be realized according to some assumptions without considering the boundary conditions such as deformation stress, stress-strain relationship and boundary friction. Firstly, the wooden model is meshed, and the position coordinates of the nodes are obtained by the coordinate measuring instrument. Or the CAD model can directly divide the grid in the computer. Assuming that the thickness of the workpiece is constant during the forming process and the area of the mesh before and after the deformation is constant, the three-dimensional space mesh is mapped to the two-dimensional plane, so that the initial blank shape and the stress distribution of the workpiece can be deduced.

Simulation method. The simulation method is to simulate the metal flow of sheet metal flange under certain assumptions, according to the similarity of mathematical description of many physical problems, through the mathematical similarity theory, using the model composed of other physical media. Laplace and Poisson equations are widely used in sheet metal forming.