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Among the metal stamping parts, metal shrapnel is a product we use more. The shrapnel also generally determines the material of the shrapnel according to the purpose and performance of the shrapnel. For example, the physical resilience is required to be used more frequently and the pressure is higher. Generally, spring steel, carbon steel or high-hardness stainless steel is selected. After forming, it is heat treated and quenched to reduce its carbon content and increase its hardness to increase the pressing life of its shrapnel.

To achieve physical properties such as easy soldering, acid and alkali resistance, and increased conductivity, copper materials are used to process shrapnel, such as phosphor copper shrapnel and beryllium copper shrapnel. Surface treatment methods such as electroplating (gold, silver, nickel, tin, etc.) can be used to meet the requirements.

The characteristics of mobile phone shrapnel are: it has conductive shrapnel, because the field of use is different, so the shape is different, and it needs to be made by punching. After the metal sheet is made into a shrapnel through a mold, it has physical resilience. If the frequency of use is higher, the pressure is higher. One side is to choose spring steel, stainless steel. After forming, it is heat treated and quenched to reduce its carbon content, and increase the pressing life of its shrapnel by increasing its hardness (that is, fatigue resistance). If the use environment is special, electroplating can be done in the process of shrapnel processing to achieve physical properties such as easy welding, acid and alkali resistance, and conductivity. Such as mechanical inner shrapnel, mobile phone button shrapnel, battery shrapnel, etc.

Furthermore, for digital products such as electronic communications, the main process performance requirements are mainly reflected in accuracy, conductivity, and weldability. Therefore, the use of copper to process shrapnel products is generally designated to use a certain grade/hardness of copper, such as phosphor copper, beryllium copper, red copper, brass, bronze, etc.