AMS 2488
Anodic Treatment, Titanium and Titanium Alloys, Solution pH 13 or Higher
Establishes engineering requirements and coating properties for alkaline anodic treatment of titanium and titanium alloys.
What AMS 2488 specifies
AMS 2488 uses a strongly alkaline electrolyte at pH 13 or higher to form functional anodic coatings on titanium. Type 1 is a measurable coating used for elevated-temperature forming and produces a dimensional increase of 0.0002–0.0004 in per surface. Type 2 is the default and produces no measurable change at 0.0001 in micrometer resolution; it is used for anti-galling, galvanic isolation, improved wear, and adhesion of solid-film lubricant. The process does not prescribe one fixed voltage: voltage is raised to maintain current density until current decays to zero. A drawing should state type, areas to anodize, masking, any compatible solid-film lubricant, and dimensional limits.
AMS 2488 types and classes
Every designation the document defines, with the thickness it requires and the tests it imposes.
| Designation | Meaning | Thickness | Requirement / test |
|---|---|---|---|
Type 1 | Coating for elevated-temperature forming. | 5–10 µm 0.2–0.4 mil | Dimensional increase of 0.0002–0.0004 in per surface; coating quality on each lot. |
Type 2 | Default anti-galling, galvanic-isolation, wear, and solid-film-lubricant pretreatment coating. | ≤ 3 µm ≤ 0.1 mil | No measurable dimensional change with a 0.0001 in micrometer; lubricated AMS 4928 wear specimens must reach at least 75000 cycles. |
Tests and the drawing call-out
Tests the document imposes
- Type 1 dimensional increase by micrometer or ASTM B244
- Type 2 no measurable dimensional change at 2.54 µm resolution
- Type 2 wear resistance of at least 75000 cycles with the specified solid-film lubricant
- Visual coating quality
- Solution pH, voltage, current-density, and temperature process controls
How to cite it
Drawing call-out
TITANIUM ANODIZE PER AMS 2488 TYPE <1|2>, [AREAS], [SOLID-FILM LUBRICANT], [MASKING]Angle brackets mark the choices the drawing must make; every finish page shows a completed example.
Finishes specified to AMS 2488
AMS 2488 — frequently asked
What is AMS 2488 Type 1 versus Type 2?
Type 1 is a 5.08–10.16 µm dimensional buildup used for elevated-temperature forming. Type 2 is the default thin anti-galling and lubricant-adhesion treatment with no measurable dimensional change at 2.54 µm resolution.
Does AMS 2488 specify an anodizing voltage?
It does not define one universal voltage. The process raises voltage to maintain the required current density until the amperage decays to zero.
Is AMS 2488 decorative color anodizing?
No. It is a functional alkaline titanium treatment for forming, anti-galling, galvanic isolation, wear, and lubricant adhesion.
AMS 2488 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 ↗