Passivation: 

About:

Passivation is a chemical process that removes various particles and residues that can permeate base materials during machining. These embedded particulates and oils often go unseen by the naked eye, and are a significant cause of metal deterioration. 

Passivation renews the surface, restoring it to original specifications, and acts as a protective coating to environmental factors like water, air, and extreme environments. Passivation does not create dimensional change, and while it does improve the surface's uniformity and surface finish, it does not change the appearance of the base metal. 

Applications: 

  • Improves and extends life of product:  improves corrosion resistance and deburrs/polishes the part
  • Stainless Steel:  in stainless steel, passivation creates a film over stainless steel that causes it to lose its chemical reactivity. This strengthen's the metals durability and corrosion resistance. 

 

Cadmium Plating:

About:

Cadmium plating serves as a "sacrificial coating," corroding before the metal beneath. It is often used with chrome conversion coatings to increase the corrosion resistance, resulting in a gold color, though other colors like olive drab are available.

Cadmium plating offers increased corrosion protection, making it the preferred coating for saltwater environments, and provides an exceptional bonding surface for adhesives. While cadmium plating is recommended for aircraft, its tendency to sublimate, outgas, and spontaneously form whiskers in a vacuum, makes is unsuitable for spacecraft.

Properties:

  • Bonding Surface: provides an exceptional adhesive bonding surface
  • Corrosion Resistance: preferred coating for saltwater environments, and in applications wherein components are reassembled often, as in aircrafts
  • Conductivity: low electrical resistance, high conductivity
  • Lubricity: high lubricity provides a high coefficient of friction and prevents galling

Applications:

  • Aerospace, Transportation, Electronics, Marine applications, Home/Office Products (window hardware, door latches, home construction)