MATERIALS FOR MANUFACTURING TERMINALS

Terminal is a common connector in industrial production, which can transmit stable signal and current to the required equipment during use. The following describes the materials used for the production terminals. 

Plastic Material for Making Terminals

1. EP: This material has good geometric stability and does not absorb water. In addition, the fire resistance of this material is very good, and its stability is better than that of ordinary thermoplastic when the temperature increases, but its toughness is poor. 

2. PA-F: This material is a nylon reinforced by fiberglass, which has strong rigidity and hardness. Compared with ordinary nylon, it can work in high temperature environment. Therefore, it is also suitable for the field of overvoltage protection. The reinforced nylon absorbs less water than normal nylon. In addition to the above differences, the other properties of the two materials are the same. The fire resistance grade of reinforced nylon is HB to V0, according to the UL94, and the type V0 material is dyed black in most cases. 

3. PC: This material has the characteristics of high hardness, good toughness, transparency, stable size, good insulation and good thermal stability. Transparent polycarbonate is especially suitable for cover or marking material. The polycarbonate is resistant to acid, saturated fat carbohydrates, gasoline, lipids and oils. The polycarbonate is less resistant to solvents, benzene, lye, acetone and ammonia. The stress cracks may be formed when it is in contact with some chemical reagents. 

4. PBT: PBT has good geometric stability. This material has high strength and heat resistance after reinforced by fiberglass. It also has reliable fire resistance and excellent electrical properties. 

5. PA66: The insulation shell of the terminal has high requirements for the quality of the material, most of the shell is made of thermoplastic nylon PA66. The cost of this plastic is very low and it is environmentally sound, which is conducive to recycling. 

Metal Materials for Making Terminals

Copper, brass and phosphorus bronze have good electrical conductivity, and their mechanical properties are also very good. For R0HS requirements, the surface of these materials needs to be tinned, which can ensure the contact resistance of the conductor is good. In addition to the electrical properties, the tin coating can also allow the conductor to have a good corrosion resistance. The solder joints of the terminals also need to be tinned, which can guarantee the good welding performance of the solder joints for a long time. The brass part of the terminal is also first plated with a layer of nickel, thus preventing the diffusion of tin. The nickel layer effectively prevents the loss of zinc atoms in brass. 

The steel material will pass through a yellow chromic acid rock layer after galvanized to provide additional passivation for the steel material. This can fully protect the surface of steel materials, strengthen the corrosion resistance of steel materials. Even if the zinc layer is destroyed, the steel material is still not easy to be corroded. Under the action of electrolyte, the metal ions of zinc will migrate to the upper surface of iron, which will provide long-term corrosion resistance for iron materials.