Automobile stamping parts should have good optimization design method

2020-07-07 15:13:03

Automotive 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 automobile appearance beautiful. The reduction of air resistance can reduce the number of stamping parts and solder joints, which can effectively reduce the cost.

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

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

Mapping geometry method. They think that the mapping from workpiece to blank can be realized according to some assumptions, without considering the boundary conditions such as deformation force, stress-strain relationship and boundary friction. Firstly, the wood model is meshed, and the position coordinates of nodes are obtained by coordinate measuring instrument. Or the CAD model is directly meshed 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 deformation is constant, the three-dimensional space grid is mapped to the two-dimensional plane, thus the initial blank shape and the stress distribution of the workpiece can be deduced.

Simulation method. According to the similarity of mathematical description of many physical problems under certain assumptions, the metal flow of sheet metal flange is simulated by using other physical medium models through mathematical similarity theory. Laplace and Poisson equations are widely used in sheet metal forming.

The description of slip line method shows that only the stamping parts with relatively simple shape can establish the corresponding slip line field. The mathematical expression of the slip line can be obtained from the solution of the characteristic square only under the very simple boundary conditions. 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. This method is based on the transformation of the characteristic line differential equation into a finite difference relationship and the characteristics of the slip line are used as the basis. Therefore, the slip line method is difficult to be popularized and applied in practical production due to its complicated mathematical operation.