This specification covers the basic physical requirements and test methods for phosphate/oil and phosphate/organic corrosion protective coatings for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection. The zinc phosphate treatment and subsequent protective coatings are classified into seven grades according to the following requirements: Grade 0A consists of a zinc phosphate coating with no additional sealer (dry); Grade 0B consists of a zinc phosphate coating with a dry organic sealer; Grades 0C, 0D, and I consist of a zinc phosphate coating with supplemental protective oil type compound; and Grades II and III consist of a zinc phosphate with a supplemental zinc-rich epoxy resin coating (with the addition of a clear organic topcoat for Grade II). These coatings may or may not have a decorative finish. The coatings shall meet the requirements specified for appearance, adhesion, corrosion resistance, coating flexibility, thread fit, and dry-to-touch characteristics. In addition, they shall also undergo humidity and coating thickness tests.

1.1 This specification covers the basic requirements for four grades of corrosion protection for fasteners. Grade A consists of a zinc phosphate coating with no additional sealer (dry), Grade B consists of a zinc phosphate coating with a dry organic sealer, Grade C, and Grade D consist of a zinc phosphate coating with supplemental protective oil type compound.

1.2 This specification is intended primarily for fasteners such as nuts, clips, washers, and other ferrous threaded and non-threaded fasteners that require corrosion protection.

1.3 These coatings may or may not have a decorative finish.