Zinc Phosphate TT-C-490 Type I and Per Mil-DTL-16232 Type Z Class 1,2,3, and 4.

In most operations where the corrosion resistance of finished workpieces must be especially high, conversion coatings are applied using zinc phosphate. This approach is widely used in the automotive industry and in certain sectors of the appliance and electronics industries. Similarly, zinc phosphating is often specified by the armed services, especially for equipment that may be exposed to severe environments. Moreover, many operations using electrocoating or powder coatings, particularly when a one-coat finish will be exposed to the weather, pretreat workpieces with zinc phosphate.

Iron Phosphate TT-C-490 Type II.

Iron phosphating is the most preferred conversion coating method for indoor equipment. For metal surfaces that do not require high corrosion resistance.

Manganese Phosphate A-A-59267 and Mil-DTL-16232 Type M.

Manganese phosphate coating has the highest hardness and superior corrosion and wear resistances of general phosphate coatings. Manganese phosphating is extensively employed to improve the sliding properties of engine, gear, and power transmission systems. The use of manganese phosphate coatings for improved corrosion resistance can be found in virtually all branches of the metal working-industry.