Example of Nadcap Manganese Phosphate on Ball Screws

Manganese Phosphate (Nadcap accredited)

Manganese phosphate coatings are applied to the surface of ferrous substrates to prevent galling and to improve break-in properties. Manganese phosphate coatings, unlike zinc phosphate coatings, also provide continued wear protection after initial break-in. The coating is formed via immersion in a dilute phosphoric acid solution and is dark grey in appearance. In applications such as firearms, the coating resists scuffing and allows for oil application and reapplication.

The standard measurement method for manganese phosphate coatings is by coating weight, and Chem Processing, Inc. applies weights ranging from 5 to 32 g/m2, as determined by customer specification. By itself, the manganese phosphate coating offers minimal corrosion protection—the heavier the coating weight the higher the degree of protection—but this protection is significantly enhanced by the application of an oil, lacquer or wax. Manganese phosphate may also serve as a base for Teflon, Xylan, powder coating or CARC paint.

Manganese phosphate also goes by the trade name Parco Lubrite, is sometimes called parkerizing in reference to finishing on firearms, or may be called phosphatizing. 

Chem Processing, Inc. offers MIL-DTL-16232 Type M, Class 4 (black) phosphate.

Note to engineers: Manganese phosphate is called a "friable" coating by industry specifications, meaning the coating can be crushed under load. It is measured by coating weight, not thickness. Burnishing of the coating will usually relieve interference in tight tolerance applications. 

Chem Processing Inc. Manganese Phosphate Capabilities:

  • Coating weights from 5 to 32 g/m2
  • Military certifications
  • Abrasive blasting and phosphate coating performed at a single facility per MIL 16232G Sec. 3.2
  • Masking for selective coating application
  • Salt spray corrosion testing per ASTM B-117
  • Bulk or rack processing

Applicable Specifications:

  • AMS 2481
  • MIL-DTL-16232
  • MIL-P-16232
  • MIL-STD-171 5.3.1
  • TT-C-490
  • PN 14.08 (UTC Aerospace Systems/Hamilton Sundstrand)

  • VGS 6.2.3 (Vetgo-Grey/GE Oil & Gas)

Common Applications of Manganese Phosphate Coatings:

  • Oil & Gas Industry: couplings, fittings, oil rig components
  • Firearms & Ordinance: (we can certify to Parkerizing™ specifications) barrels and other components that are frequently and repeatedly oiled for lubrication
  • Aerospace: actuator components, fastening systems
  • Gears & Bearings: break-in and lubricity
  • Marine Equipment: break-in of engine components.

Chem Processing Inc. offers manganese phosphate coating services to Illinois, Wisconsin, Iowa, the Midwest and beyond. CPI is strategically located by highway routes to Chicago, Milwaukee, Madison, St. Louis, and Minneapolis. The CPI facility is minutes from Rockford Chicago International Airport , a major Midwestern air freight hub, enabling efficient door-to-door delivery across the United States or across the globe.