• Latest
  • Trending

Contact Finishes

October 2, 2023

binder Unveils Quick Lock Ruggedized Power Bayonet

October 3, 2023

Connector Temperature Rise and Derating

September 29, 2023

Connector Raw Material Costs Decreased 6.9 Percent in Q2 2023

September 27, 2023

Webinar PCBs: RIGID.flex with Flexible Soldermask or Coverlay?

September 20, 2023

Samtec Expands with a New Cable and RF Connector Manufacturing Facility in Pennsylvania

September 20, 2023

KYOCERA AVX Unveils New Series Poke-Home Single Contacts

September 20, 2023

Murata Announced Completion of New Plating Research Building in Japan

September 19, 2023

RF Compression-Mount Connectors Enhance Millimeter Wave Designs

September 1, 2023

Würth Elektronik Introduces micro SIM Card Interface with Card Detection

August 31, 2023

Yamaichi Extended Board-to-Cable Connectors for Battery Management

August 15, 2023

How the Connector Blade Assignments Impact Power Integrity 

August 15, 2023

How to Maintain 50 Ohms RF Transmission Path

August 15, 2023
  • Privacy Policy
inter-connection blog
  • Home
  • Knowledge base
  • Sister Sites
    • Passive Components Blog
    • PCNS Symposium
    • The Passives Times
    • EPCI Home
  • About
No Result
View All Result
  • Home
  • Knowledge base
  • Sister Sites
    • Passive Components Blog
    • PCNS Symposium
    • The Passives Times
    • EPCI Home
  • About
No Result
View All Result
inter-connection blog
No Result
View All Result

Contact Finishes

October 2, 2023
A A

A contact finish, C in Figure 1.3, consists of a surface coating, generally produced by electroplating, over the contact spring to provide two performance benefits:

Corrosion protection for the contact springs and optimization of the electrical and mechanical characteristics of the contact interfaces. As mentioned, copper alloys are typically used as connector contact springs and are susceptible to corrosion in typical connector operating environments. The contact finish provides corrosion protection by covering the exposed copper to protect it from the operating environment. “Optimization” of contact interface performance is provided by influencing the corrosion and wear characteristics of the contact interface. These functions will be discussed in Chapter II.

RelatedPosts

Connectors Explained

KYOCERA AVX IDC RF Shark Fin Connectors for Antennas Vehicle Systems

Binder Launches M12 Panel L-coded Mount Connectors

There are two general types of contact finishes, noble and non-noble. Gold is the predominant noble metal finish material. The term “noble” refers to the fact that gold is not susceptible to corrosion. Tin is the most common non-noble finish material. Tin is susceptible to corrosion by the formation of a thin self limiting thickness of tin oxide. This oxide protects the contact interface from further corrosion, but is readily displaced on mating of the connector to provide the desired metal-to-metal contact interface.

A brief overview of each finish will be provided here with details to follow in Chapter II/2.1 Contact Finishes.

Noble Contact Finishes
A noble metal finish is a system consisting of three components. A surface coating of noble metal, gold or palladium alloy, an underplate, generally nickel, and the base metal of the contact spring as shown in Figure 1.14. For Telecom or harsh environment gold and nickel are typically electroplated to thicknesses of the order of 0.4 to 0.8 µm (15 to 30 microinches) for gold and 1.25 to 2.50 µm (50 to 100 microinches) for nickel. Noble metal finishes are used in high performance and high reliability applications.

Fig. 1.14: Noble metal contact finish

The gold top coat provides the corrosion protection. It also allows for performance optimization in that the hardness of the gold can be controlled to influence the friction and wear behavior of the mating interface. The nickel underplate provides several performance advantages noted here for reference with details to follow in Chapter II/ Design/Selection/Assembly.

The nickel underplate:
• reduces the susceptibility to pore corrosion
• reduces corrosion migration
• provides a diffusion barrier to base metal migration
• improves the mating durability of the contact interface

The contact spring is included in the noble metal finish system for both electrical and mechanical reasons. The electrical reason is that the distribution of the current flow to the contact interface is dependent on the conductivity of the contact spring. The mechanical reason is that the stresses applied to the contact interface during mating can extend down into the spring material due to the small thicknesses of the gold and nickel platings.

Non-noble Contact Finishes
The dominant non-noble finish is tin, with silver and nickel being used in selected applications. Tin is used in industrial and commercial applications including white goods, while nickel and silver are primarily used in battery contact and power contacts respectively.

These finishes are also typically electroplated, but tin can also be applied by dipping or reflow processes. Tin finish thicknesses are in the range of 2.5 to 5.0 µm (100 to 200 microinches). Nickel and silver thicknesses are generally in the range of 1.25 to 2.5 µm (50 to 100 microinches).

Related

Source: Wurth elektronik
Next Post

The Contact Interface and Contact Physics Overview

The Mechanical Interface: Friction and Wear/Durability

The Electrical Interface: Contact Resistance

Popular Posts

  • Crimped Connections

    0 shares
    Share 0 Tweet 0
  • THR (Through Hole Reflow) Technology: Introduction & History:

    0 shares
    Share 0 Tweet 0
  • Basic Principles of Connectors

    0 shares
    Share 0 Tweet 0
  • The Electrical Interface: Contact Resistance

    0 shares
    Share 0 Tweet 0
  • Space Saving Molex Connector in AR/VR System designs

    0 shares
    Share 0 Tweet 0

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Archive

2023
2022

Newsletter Subscribe

  • About
  • Inter-Connection Blog
  • Inter-Connection News
  • Knowledge base
  • NEWS
  • Privacy Policy
  • Sister Sites
  • Subscribe

© 2023 EPCI - Premium Passive Components & Inter-Connect News

No Result
View All Result
  • About
  • Inter-Connection Blog
  • Inter-Connection News
  • Knowledge base
    • Applications
    • Basic Principles of Connectors
    • Design Selection Assembly
  • NEWS
  • Privacy Policy
  • Sister Sites
  • Subscribe

© 2023 EPCI - Premium Passive Components & Inter-Connect News

This website uses cookies. By continuing to use this website you are giving consent to cookies being used. Visit our Privacy and Cookie Policy.