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.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

1. Scope

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.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

B117 Practice for Operating Salt Spray (Fog) Apparatus

F1470 Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection

Keywords

coating; corrosion; fasteners; protection; phosphate; resistance; rust; Corrosion-resistant coatings--specifications; Corrosive service applications--bolting/fastening applications; Electrodeposited coatings--specifications; Fasteners (metal)--specifications; Organic coatings--specifications; Phosphate coatings; Protective coatings--specifications; Zinc electrodeposited coatings--specifications; Zinc phosphate (ZnP) coatings

ICS Code

ICS Number Code 21.060.01 (Fasteners in general); 25.220.60 (Organic coatings)

Citing ASTM Standards

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