A variety of phosphate-coated metal products including gears, ball joints and rods.

Manganese Phosphate, Zinc Phosphate and Iron Phosphate Coatings

Manganese Phosphate, Zinc Phosphate and Iron Phosphate are the treatment of iron or steel by immersion in a solution of phosphoric acid and other compounds. During the process the surface of the metal is chemically converted to form a protective layer of manganese phosphate, zinc phosphate or iron phosphate crystals.

The physical characteristics of the base metal and the pretreatment methods used determine the size and color of the crystalline finish.

  • Black for Manganese phosphate
  • Grey to Black for Zinc Phosphate
  • Light Grey for Iron Phosphate

Phosphate coatings are used as a base for subsequent coatings such as:

  • Paints
  • Waxes
  • Water Soluble Oils
  • Dry Film Lubricants

Phosphate Coating Services We Offer

  • Manganese Phosphate
  • Zinc Phosphate
  • Iron Phosphate
  • Rack and Barrel Processing

Manganese Phosphate Coating is applied when anti-galling and wear resistance are required. It also has the capability to retain oil, improving lubricity and corrosion resistance even further. Commonly used on bearings, bushings, fasteners and other industrial parts, including transmission systems, motor vehicle components, leaf and coil springs, and brake and clutch assemblies.

Zinc Phosphate Coating is applied when excellent corrosion resistance is needed.  Zinc phosphate is mainly used as rust proofing and as Chemical Agent Resistant Coating (CARC) on military equipment including munitions, ground and aviation, allowing them to withstand harsh environmental conditions.

Iron Phosphate Coating is applied when strong adhesion of a subsequent painting is required.

Rack Processing involves attaching parts to metal racks with hooks, wires or spring fingers, allowing components to stay fixed in place during immersion into the plating solution. Rack processing is ideal for delicate parts not able to tolerate the tumbling produced by barrel processing. Rack processing can also work well for large or complex components, plating intricate details with precision. Rack Processing is a favored method used by industries where a high-caliber finish is critical, such as automotive, military, medical and electronics.

Barrel Processing provides a uniform, smooth coating. Parts are rotated slowly while submerged in a plating solution. Barrel processing increases defense and prevention of corrosion and offers an economical solution for plating high volumes of small, durable parts such as fasteners, nuts and bolts. Barrel plating is a good option for plating metal parts of various shapes and sizes.

Phosphate Coating Benefits

  • Reduction of Metal to Metal Galling
  • Performs Well in High Torque Applications
  • Good Base Coating
  • Corrosion Resistance
  • High Lubricity

Phosphate Coating Applications

  • Automotive
  • Home Appliances
  • Military and Defense
A black zinc metal finish is applied to fasteners.


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