AMS 2472
Anodic Treatment of Aluminum Alloys, Sulfuric Acid Process, Dyed Coatings
Establishes processing and performance requirements for dyed sulfuric-acid anodic coatings on aluminum alloys.
What AMS 2472 specifies
AMS 2472 governs dyed sulfuric-acid anodizing for aerospace aluminum parts. Class 1 is principally a marking coating with at least 600 mg/ft² unsealed coating weight; Class 2 is a decorative coating with at least 2500 mg/ft². The current revision also addresses high-copper 2000-series alloys separately. Coated qualification panels receive at least 336 hours of ASTM B117 salt spray, and color and appearance remain lot acceptance features. A drawing should state Class 1 or 2, color, significant surfaces, masking, contact locations, and any dimensional or sealing requirement.
AMS 2472 types and classes
Every designation the document defines, with the thickness it requires and the tests it imposes.
| Designation | Meaning | Coating weight | Requirement / test |
|---|---|---|---|
Class 1 | Dyed coating principally for identification or marking. | Minimum 600 mg/ft² unsealed. | Coating weight, color, appearance, and 336 h salt spray. |
Class 2 | Heavier dyed coating for decorative service. | Minimum 2500 mg/ft² unsealed. | Coating weight, color, appearance, and 336 h salt spray. |
Tests and the drawing call-out
Tests the document imposes
- Unsealed coating weight by ASTM B137
- ASTM B117 salt spray for at least 336 h
- Color and visual appearance
- Sealing and process-control tests
How to cite it
Drawing call-out
ANODIZE PER AMS 2472, CLASS <1|2>, COLOR <COLOR>, <THICKNESS IF REQUIRED>, <MASKING>Angle brackets mark the choices the drawing must make; every finish page shows a completed example.
Finishes specified to AMS 2472
AMS 2472 — frequently asked
What is the difference between Class 1 and Class 2?
Class 1 is principally for dyed marking and has a 600 mg/ft² minimum unsealed coating weight. Class 2 is decorative and raises that minimum to 2500 mg/ft².
Does AMS 2472 guarantee an exact color?
No anodize color is independent of alloy, temper, pretreatment, and geometry. State the color and use an approved physical sample when a close cosmetic match is required.
Is thickness implied by the class?
The classes are defined through application and coating-weight requirements, not a single universal thickness. Add a thickness requirement when fit or dimensional buildup is critical.
AMS 2472 is copyrighted by SAE International. This page explains the document so a drawing can be read; it does not reproduce the standard. Purchase the current edition from the publisher. Official source ↗