Manufacturing Processes and Logistics for Licensing

Delphi Silver Corrosion Reduction Process

Delphi's Silver Corrosion Reduction Process is a method of treating silver-containing surfaces to reduce corrosion.

Delphi's approach electrochemically forms an iodine-containing layer on a silver surface as a means of protecting the silver surface from sulfur. The surface is protected from wear by the thin surface layer that also functions as a solid lubricant, while preserving a low electrical resistance surface (vs. regular oxidation with no protective layer).

The Delphi Silver Corrosion Reduction Process can replace a stable but more costly fluid-based silver lubrication approach.


  • Allows sustained performance of an electrical contact by providing reliable and stable interconnections between the electrical contacts of electromechanical devices
  • Permits a suitably low resistance electrical contact to the underlying silver layer
  • Iodine-containing layer on silver contact surfaces
  • Improves the sulfur-tarnish resistance, friction and wear characteristics, and preserves the electrical stability vs. a bare silver surface
  • Provides a frictional coefficient that is 5 times lower than a bare, clean silver surface
  • Layer does not migrate away from the point of contact with time or during wear
  • Surface resistance is low and electrically stable for conduction of electric current
  • Increases lifetime of sliding switch cycles 
  • Improved fretting endurance
  • Economical and efficient for mass-production

Silver surface after test

Typical Applications

Using a protective iodine-containing coating on the surface of a silver-containing layer, Delphi's Silver Corrosion Reduction Process is particularly useful for the following applications:

  • Electrical device contacts
  • Terminals
  • Switches
  • Other electrical connectors

It can be used in the following markets:

  • Automotive
  • Consumer
  • Industrial


Manufacturing Processes & Logistics: Processes

Patent Number

7,575,665, Method of reducing corrosion of silver containing surfaces


Harrington; Charles R., Aukland; Neil R.