The Basic Characteristics Of Stamping Forming Processing

There are many stamping forming processes used in production time, with various forms and names, but the essence of plastic deformation is the same. Stamping forming has the following very prominent characteristics.
(1). The pressure per unit area perpendicular to the direction of the plate is not sufficient to cause plastic deformation of the plate in the direction of the plate. Since the quality of pressure per unit area perpendicular to the direction of the plate is much less than the internal stress in the direction of the plate, most of the stamping deformation can be treated as plane stress state approximately, so that the analysis of deformation mechanics and the calculation of process parameters are greatly simplified.
(2). Because the relative thickness of the sheet hair used in stamping is very small, the anti-instability ability under the action of compressive stress is also very poor, so it is difficult to successfully complete the stamping process in the free state without the anti-instability device (such as the blank holder, etc.). Therefore, the elongating stamping process, which is dominated by tensile stress, is more than the compression process, which is dominated by compressive stress.
(3). During stamping, the stress inside the sheet hair embryo is equal to or less than the yield stress of the material. At this point, stamping and volume forming are very different. Therefore, the influence of the hydrostatic pressure component in the stress state of the deformation zone on the forming limit and deformation resistance has lost its importance in the volume forming. In some cases, it can even be completely ignored. Even if it is necessary to consider, the treatment methods are not the same.
(4). In stamping forming, the constraint effect of the die on the sheet hair embryo is relatively light, unlike the forced forming (such as die forging), which is realized by the full contact of the cavity with the shape of the workpiece. In stamping forming, in most cases, the sheet hair embryo has some degree of freedom, often only one surface is in contact with the die, and sometimes there is even a deformed part of the surface on both sides of the sheet which is in contact with the die. In this case, the deformation of this part of the hair embryo is controlled by the external force exerted by the mold on its adjacent parts. This is the case, for example, for the hanging part of the forming of spherical and conical parts and for the winding of the end of the tube.
Because stamping has some of the above characteristics in deformation and mechanics, the stamping technology has also formed some characteristics different from volume forming.
Because it is not necessary to apply a large unit pressure on the surface of the sheet wool to form it, the research on the strength and stiffness of the die is not very important in the stamping technology, on the contrary, the development of simple die technology. For the same reason, the process of forming by gas or liquid pressure has been developed.
Due to the plane stress state or the more simple strain state (compared with the volume forming), the current research on the deformation and mechanical parameters of the hair embryo in the stamping forming sink is more in-depth, and it is possible to use reasonable scientific methods for stamping processing. With the help of electronic computer and advanced testing means, on the basis of real-time measurement and analysis of sheet metal properties and stamping deformation parameters, the research work of realizing intelligent control of stamping process is also carried out.
After people have a deeper understanding of the stamping forming process, they have realized that stamping forming has a very close relationship with raw materials. Therefore, the study of sheet metal stamping performance, namely formability and shape stability, has become an important content of stamping technology. The research on the stamping performance of sheet metal is not only the need of the development of stamping technology, but also promotes the development of iron and steel industry production technology, and provides a reliable foundation and basis for improving the quality of sheet metal.