Aluminum Anodizing Services for Corrosion Resistance, Hardness & Durability
MIL provides spec-driven aluminum anodizing—including Type I, II, and III—to enhance corrosion resistance, wear performance, hardness, and dye absorption for precision components used in aerospace, defense, medical, and industrial applications.
All Services
High-Performance Anodizing for Critical Metal Components
Aluminum anodizing is an electrochemical process that transforms the surface of aluminum into a controlled, hardened oxide layer that improves corrosion resistance, wear resistance, and coating adhesion.
MIL applies anodize coatings to meet stringent MIL-spec, AMS, and OEM requirements while maintaining tight dimensional tolerances and consistent film build.
Aluminum Anodizing Highlights
- Type I Chromic Acid Anodize: 0.00005″–0.0001″
- Type II Sulfuric Acid Anodize: 0.0001″–0.0008″
- Type III Hardcoat Anodize: 0.0008″–0.003″
- Available in multiple dyed color options
- Excellent corrosion and wear protection
- Ideal pretreatment for solid film lubricants, prime, and paint
- Numerous aerospace prime approvals and Nadcap accreditation
- Suitable for close-tolerance, complex, and multi-step part workflows
How the Aluminum Anodizing Process Works
Step 1 — Surface Preparation
Proper pre-treatment is essential for ensuring a uniform oxide layer. MIL performs:
- Degreasing and precision cleaning
- Etching or deoxidizing where required
- Masking of tight-tolerance surfaces
- Controlled racking to support consistent electrical contact
Step 2 — Electrochemical Anodizing
Parts are immersed in a controlled acid electrolyte and energized to thicken the natural oxide layer.
Depending on the required anodize type, MIL can achieve:
- Thin, protective Type I layers
- Versatile, dye-compatible Type II layers
- Extremely hard, wear-resistant Type III layers
Step 3 — Dyeing (Optional)
For applications requiring color identification, aesthetics, or UV-stable coloration, MIL offers a range of dye colors with excellent absorption due to the anodized pore structure.
Step 4 — Sealing
Sealing closes the anodic pores to lock in dyes and enhance corrosion protection. MIL performs:
- Hot water sealing
- Nickel acetate sealing
- Other spec-driven sealing methods based on customer requirements
Step 5 — Inspection & Verification
All anodized parts undergo rigorous testing, including:
- Thickness measurement
- Seal quality assessment (e.g., dye spot)
- Adhesion and visual inspection
- Documentation aligned with spec requirements
Why Work With MIL for Aluminum Anodizing?
Aerospace-Level Process Control
MIL’s Nadcap accreditation and long list of prime approvals ensure compliant, repeatable anodizing for the most demanding manufacturing programs.
Consistent Thickness & Color Uniformity
Controlled electrical parameters, racking, and bath chemistry deliver reliable film thickness—even on complex geometries.
Integrated Multi-Process Workflows
Anodizing frequently precedes or follows other processes such as:
- Solid Film Lubricants
- Chem Film
- Prime & Paint
- Passivation
MIL performs all of these services in-house to reduce handling risk and lead time.
Trusted by Machine Shops & OEMs for 80+ Years
MIL is known for handling complex, tight-tolerance parts and ensuring they meet spec—every time, without exception.
Applications & Industries Served
Component Types
- Brackets, housings, and machined structures
- Aircraft interior and exterior hardware
- Actuation system parts
- Precision hardware requiring wear protection
- Components needing cosmetic or color coding options
Industries
- Aerospace & defense
- Space systems
- Medical devices
- Industrial equipment & instrumentation
- Specialty manufacturing and R&D
Frequently Asked Questions About Aluminum Anodizing
Type I is thin and corrosion-resistant; Type II offers thicker films and dyeing options; Type III is a hardcoat layer with high wear resistance.
Typical ranges:
- Type I: 0.00005″–0.0001″
- Type II: 0.0001″–0.0008″
- Type III: 0.0008″–0.003″
Yes—MIL controls growth precisely and masks critical surfaces to maintain dimensional integrity.
Yes. Type II anodize is ideal for dye absorption, and MIL offers multiple color options.
Absolutely—anodized surfaces provide excellent adhesion for solid film lubricants, primers, and paints.
Most aluminum alloys can be anodized, though results vary based on composition. MIL can recommend the best approach based on alloy and application.
Get Started Today
Fast, accurate estimates for Type I, II, and III anodizing—including multi-process finishing workflows.
Need help determining the correct anodize type, thickness, or pre-treatment? MIL’s engineering team is here to advise.
When Your Parts Carry Risk, We Carry the Load. 82 Years of Flight-Critical Confidence.