18650 Battery Clip

4 Reasons why use Nickle as base plating?

Mostly we see the connector terminal,  components contact surface plating is Gold or Tin over Nickle. Do you know why to use Nickle as a base plating? You could find the answers the below reasons:

1. Leveling layer

The nickel-base plate can be used as a leveling to make the surface finish with lower roughness, thereby reducing friction, thereby improving the wear resistance of gold-plated connectors or contacts.

2. Bearing layer

The nickel plating layer is a hard plating layer, which provides the basis for subsequent gold plating. This prevents the hard gold deposits from cracking and improves the overall wear resistance of gold-plated connectors or contacts used in dynamic cycles.

3. Diffusion barrier

Alloying elements such as copper, zinc, and lead can diffuse into the gold plating through solid-state diffusion, thereby forming weak intermetallic or eutectic at the gold/substrate interface. This consumes some effective gold and reduces the integrity and function of the deposit, and the nickel-base plate also forms an effective barrier to prevent diffusion and migration at the gold/substrate interface.

4. Corrosion inhibitor

The nickel-base plate can work with the final gold plating or Tin plating layer to isolate the substrate from the environment, thereby acting as an effective corrosion inhibitor, which can help reduce the total gold thickness or Tin required to prevent the gold/Tin from corroding the substrate through the deposit. Besides, nickel liners (such as high-phosphorus electroless nickel) have excellent corrosion resistance, while high-purity nickel (such as nickel sulfamate) provides the best welding foundation.

Therefore, in the gold-plated / tin-plated connectors and contacts, the type and thickness of nickel should be carefully considered. The thickness of the nickel-base plate can be changed according to the design requirements of the connector or contact, but the minimum thickness is usually recommended to be 80uin (2um). What Jiatel does is 80~120μ” Nickle thickness for ensuring its good solderability.