NAS 4006 Compliance
High Purity AlumiPlate® Aluminum for NAS 4006 Fastener Systems
99.99% pure electroplated aluminum is an ideal coating for fasteners and fastener systems to meet NAS 4006 coating requirements. AlumiPlate Inc. can certify full compliance to this exacting standard.
NAS 4006 is the National Aerospace Standard that governs the application of aluminum coatings for fasteners, including titanium fasteners. NAS fastener specifications are commonly used for high strength steel, titanium, Inconel and Hastelloy aerospace fasteners. This standard was created for aerospace applications (military, commercial aviation, etc.) that require resistance to environmental corrosion or to eliminate galvanic corrosion with dissimilar metals. The required coating thickness is 0.0002” – 0.0005”. Processing at temperatures higher than 400 °F is not allowed. As long as performance requirements are met, any coating process can be used (strike layers are allowed).
NAS 4006 Aluminum Fastener Coating Specification Requirements
This National Aerospace Standard fastener document specifies aluminum coating performance criteria and test methods for thickness, coverage, appearance, adhesion, fluid resistance, paint stripper resistance, embrittlement, corrosion protection and heat protection.
Thickness – 0.0002 to 0.0005 inches per MIL-STD-1312
Coverage and Appearance – visual examination for coverage and uniformity (pin holes, porosity, blisters, nodules and pits not allowed).
Adhesion – destructive adhesion test showing no separation under magnification (scrape or bend to rupture)
Fluid resistance – no blistering or loss of adhesion when exposed to phosphate ester hydraulic fluid (Aerosafe 2300 or equivalent) at 150 °F for 30 days.
Paint stripper resistance – no blistering or loss of adhesion when exposed to MIL-R-81294 paint stripper at room temperature (75 °F +/- 5 °F).
Embrittlement – no cracking after installing fasteners (using 80% of rated ultimate load) in 7075-T6 aluminum block. Metallurgical examination of polished and mounted samples after exposure for 72 hours at 300 °F +/- 10 °F.
Corrosion protective properties – same or better performance as cadmium plated control block in a modified accelerated exposure procedure (modified 14-day Acid-Salt Spray Test per ASTM B-287). This test measures inorganically and organically coated ferrous and non-ferrous metals for their relative corrosion resistance at moderately elevated temperatures (35 °C / 95 °F).
Heat Protection – destructive adhesion test showing no separation under magnification (scrape or bend to rupture) after heating at 375 °F +/- 25 °F for four (4) hours and air cooling.
Aluminum electroplating meets all specification requirements for National Aerospace Standard 4006 bolts, with confirming order certifications.
Contact us for more information or to discuss your application in more detail. As experts on the NAS 4006 approval process, you can be certain that your fasteners will meet this rigorous standard.
Contact us to request more information on aluminum plating for NAS screw specifications.
Ready to utilize high-purity electroplated aluminum for your fastener application? We can help you meet NAS 4006 specification requirements with our 99.99% pure aluminum coatings. Reach out to our helpful team today to get started!