The composite stamping mentioned in this article does not refer to the combination of stamping processes such as cutting, stretching, and punching, but rather to the combination of stamping technology with other processing techniques, such as the combination of stamping and electromagnetic forming, the combination of stamping and cold forging, and the combination of stamping and mechanical processing. Today, we will focus on introducing the latest technology in stamping processing.

1. Composite process of stamping and electromagnetic forming

Electromagnetic forming is high-speed forming, which not only expands the forming range of aluminum alloys, but also improves their forming performance. The specific method of forming aluminum alloy coverings by composite stamping is to use a set of convex and concave molds to install electromagnetic coils at the sharp corners and difficult to form contours of the aluminum alloy coverings, and form them by electromagnetic methods. Then, a pair of molds are used to form the easy to form parts of the coverings on a press machine, and the pre formed parts are subjected to high-speed deformation using electromagnetic coils to complete the final forming. It has been proven that this composite forming method can obtain aluminum alloy coverings that are difficult to obtain with a single stamping method.

The latest research shows that magnesium alloy is a metal with high specific strength, good stiffness, and strong electromagnetic interface protection performance. Its application prospects in industries such as electronics and automobiles are very promising, and there is a trend to replace traditional iron alloys, aluminum alloys, and even plastic materials. At present, magnesium alloy components used in automobiles include instrument panels, seat frames, engine covers, etc. Magnesium alloy tube components are also widely used in cutting-edge industrial fields such as aircraft, missiles, and spacecraft. But the dense hexagonal lattice structure of magnesium alloy determines that it cannot be stamped at room temperature. Now people have developed a mold that combines heating and forming to punch and form magnesium alloy products. The forming process of this product is as follows: during the descent of the punch slider, the upper and lower molds clamp and heat the material, and then form it in an appropriate motion mode.

This method is also applicable for the connection of formed products and the composite forming of various products inside the punch press. Many difficult to form materials, such as magnesium alloys, titanium alloys, and other products, can be stamped and formed using this method. Due to the requirement for the punch slider to have a pause function during the descent process in order to provide time for material heating, a new concept of punch press - CNC crankshaft servo motor punch press - has been developed. This punch press can also achieve composite processing including threading, riveting and other processes in the stamping die, effectively expanding the scope of stamping processing and laying a solid foundation for the widespread application of magnesium alloys in the plastic processing industry.

2. The combination of stamping and cold forging

General sheet metal stamping can only form parts with equal wall thickness, and thinning and stretching methods can only obtain thick bottomed thin-walled parts at most. The limitations of stamping forming limit its application range. In the production of automotive parts, it is common to encounter thin-walled but unevenly thick parts that can be easily formed using a composite plastic forming method combining stamping and cold forging. Therefore, the combination of stamping and cold forging can expand the range of sheet metal processing. The method is to first use stamping method for pre forming, and then use cold forging method for final forming. The advantages of using stamping cold forging composite plastic forming are: firstly, the raw materials are easy to purchase at a low cost, which can reduce production costs; The second is to reduce the large forming force required for a single cold forging, which is beneficial for improving the life of the mold.