Material selection directly impacts the overall product performance and is a key aspect of design. Taking plastic materials as an example: if the design is based on UL94 or V-0 flame retardancy, it's crucial to carefully review the technical parameters in each material's property data sheet to ensure they meet product standards, such as passing impact resistance and aging resistance tests. In the hardware sector, the selection of the TP (Transfer Plate) sheet material is particularly important because it must meet both certain conductivity (current) and elasticity requirements. This presents a challenge for engineers, but it's precisely this aspect that connector manufacturers are pursuing in elastic components. Many hardware material manufacturers are working on this. Conductivity directly affects temperature rise and contact resistance. The quality of elasticity is related to the material's chemical elements, elastic modulus, hardness, and tensile strength. The elastic modulus is calculated using the fourth strength theory formula in materials mechanics.
The higher the conductivity of the material, the lower the contact resistance and the lower the temperature rise. The insertion and extraction force has a quadratic relationship with the contact resistance. Contact resistance is mainly divided into: compression resistance, film resistance, and volume resistance (the resistance of the conductor itself). Film layer resistance accounts for 70-80% of the total resistance and is a major factor affecting connector lifespan, so it should be given full attention. Taking gold plating and silver plating as an example, although silver has higher conductivity than gold, its chemical stability is not as good as gold, resulting in a much higher film layer resistance than gold plating. Therefore, understanding the relationship between the above is of guiding significance for our material selection and is a prerequisite for product design.
