Ano
Specification
MIL-A-8625 Anodizing, and How to Read the Callout
The controlling specification for anodic coatings on aluminum. If your drawing carries an 8625 callout, this page explains what it is asking for, and we run it in Paoli every working day.
What the specification covers
One Specification, Three Coating Types, Two Classes
MIL-A-8625 governs anodic coatings on aluminum and aluminum alloys for military and aerospace work. It defines the coating types, the dyed and non-dyed classes, sealing requirements, and the testing that proves a lot conforms to what was ordered.
Most engineers who search the bare specification number are holding a drawing with a line on it like ANODIZE PER MIL-A-8625 TYPE II CLASS 2, BLACK. That line is already a complete instruction. It names the process, whether the part is dyed, and what color. We run it exactly as written, and if any element of it is missing or contradicts another, you hear about it before the parts go in a tank.
Reading the callout
What Each Element of an 8625 Callout Means
Four elements do all the work. Get these right on the drawing and there is almost nothing left to discuss before the job runs.
| ELEMENT | WHAT IT SPECIFIES | EXAMPLE |
|---|---|---|
| Type | Which coating process | Type II sulfuric, Type III Hard Coat |
| Class | Dyed or not dyed | Class 1 clear, Class 2 black or color, on Type II and on Hard Coat |
| Seal state | Sealed or non-sealed | Non-sealed wears best, sealed resists corrosion best |
| Thickness | Coating build, when stated | Per the drawing dimension |
Type I is Chromic Acid Anodizing, a thin coating we do not run. When a drawing carries a Type I callout we say so up front instead of substituting Type II, because the two are not interchangeable and the difference tends to surface at somebody else's inspection rather than ours. The full specification text is published free on the government's ASSIST library at quicksearch.dla.mil.
Three Callouts, Read Element by Element
ANODIZE PER MIL-A-8625 TYPE II CLASS 2, BLACK. Type II is sulfuric acid anodizing, Class 2 means the coating is dyed, and BLACK names the dye. Nothing else is needed for us to run it.
ANODIZE PER MIL-A-8625 TYPE II CLASS 1. The same sulfuric process with no dye, which is the clear finish.
ANODIZE PER MIL-A-8625 TYPE III CLASS 1. Hard Coat with no dye. Add the seal state when the part needs one: non-sealed wears best, sealed resists corrosion best. If the drawing is silent on the seal state, we flag it before running.
THE LINE · PAOLI, INDIANAWhere it runs
Which of Our Tanks an 8625 Callout Goes Into
MIL-A-8625 work is not a specialty lane here that gets stood up when an order arrives. It is most of what the shop runs. Both types run in our own tanks, on the same line, with quality control checking each batch as it moves, not only at the end.
Defense work rides on our CAGE code, 9CSF4, and runs on the same schedule as commercial work because it goes through the same building. That is the practical reason a compressed delivery order is a question about capacity that week, not about capability.
Questions
MIL-A-8625 Questions
Which MIL-A-8625 Types Does AnoPRO Run?
Type II Sulfuric Anodizing and Type III Hard Coat, in clear, black, and dyed colors, Class 1 and Class 2. We do not run Type I Chromic Acid Anodizing, and when a drawing carries a Type I callout we say so before quoting instead of substituting Type II.
What Is the Difference Between Class 1 and Class 2?
Class 1 is non-dyed and Class 2 is dyed. The class rides on either type, so a black Hard Coat part is a Type III Class 2 coating and a clear anodized part is Type II Class 1.
Can Type III Hard Coat Be Colored, or Only Clear and Black?
It can be colored. Buyers commonly assume Hard Coat only comes in gray or black, but a Type III Class 2 callout can name other colors, and we run them on request. The dense coating reads darker under dye than Type II does, so send a color target and we will confirm the shade on your alloy before quoting.
Does MIL-A-8625 Require Sealing?
The callout decides. Non-sealed coatings give the best wear resistance and sealed coatings give better corrosion protection, which is a real trade, not a preference. If your drawing is silent on the seal state, we flag it before running.
How Fast Can You Turn MIL-A-8625 Work?
Standard turnaround is 3 to 5 days from the day parts reach our dock, with expedites as fast as same day, and pickup and delivery inside 100 miles of Paoli.
Do You Supply Certification With 8625 Work?
Tell us what your customer requires with the request for quote and we will confirm what we can document before you accept the quote, so a gap turns up now and not at delivery.
Where to go next
The Service Pages Behind Each 8625 Callout
This page covers what the specification asks for. If you already know which type your part needs, these pages cover how we actually run it and what to expect back.
Send the 8625 Callout Exactly as Written.
We quote from the drawing and put the date on the quote. 3 to 5 days standard, same-day expedite available.