Anodizing Services
Yijin Solution provides anodizing for aluminum parts. All finishing is done in-house. Work is inspected under our ISO 9001 quality system. Anodizing specifications are confirmed at the quote stage.
- Type II and Type III anodizing on 6000, 7000, 2000, and 5000 series aluminum alloys
- Clear, color, and hard coat finishes
- MIL-A-8625 certified with Zeiss CMM inspection on every order
- Prototype quantities to full production runs
Join 3000+ companies who work with Yijin Solution
Anodizing Overview
Anodizing converts the aluminum surface into a hard, stable oxide layer that becomes part of the base metal rather than sitting on top of it. The result is corrosion resistance, increased surface hardness, and consistent color that does not chip or peel.
When anodizing is specified, masking, dimensional compensation, and alloy-specific behavior are confirmed during the DFM review before production begins. For parts that require a matte or satin pre-finish, bead blasting or tumbling can be added upstream of anodizing in the same order.
Sheet metal fabrication is one stage in a larger product development process. We support the full path from initial concept through engineering review, prototyping, design validation, and volume production.
Anodizing Types and Specifications
The table below compares the three anodizing types we process, referenced to MIL-A-8625.
| Propiedad | Type I (chromic) | Type II (sulfuric) | Type III (hard coat) |
|---|---|---|---|
| Espesor | 0.5 to 7.5 µm | 5 to 25 µm | 25 to 100 µm |
| Hardness (Vickers Hardness, HV) | 200 to 300 | 200 to 400 | 400 to 600 |
| Opciones de color | Clear only | Clear, black, red, blue, gold, custom | Natural dark, black |
| Texture | Thin, slightly matte | Smooth matte to satin (depends on pre-finish) | Coarser matte, slightly textured |
| Lo mejor para | Aerospace, thin walls | General corrosion, decorative | High wear, sliding mechanisms |
| Estándar | MIL-A-8625 Tipo I | MIL-A-8625 Tipo II | MIL-A-8625 Tipo III |
Materials We Anodize
Anodizing behavior varies significantly across aluminum alloy families. The table below covers the alloys we anodize most frequently and the finish characteristics buyers should expect from each.
Alloy 6000 series
| Common grades | Anodizing behavior |
|---|---|
| 6061-T6, 6063 | Excellent. Best all-round choice for anodized parts. Produces uniform, consistent color across Type II and Type III. |
Alloy 7000 series
| Common grades | Anodizing behavior |
|---|---|
| 7075-T6 | Good. High zinc content may produce a yellowish tint on clear anodize. Performs well with black and darker dye colors. |
Alloy 2000 series
| Common grades | Anodizing behavior |
|---|---|
| 2024-T3 | Difficult. High copper content causes uneven dye absorption and mottled color. Type I recommended where anodizing is required. |
Alloy 5000 series
| Common grades | Anodizing behavior |
|---|---|
| 5052, 5083 | Good. Suitable for sheet metal anodizing. Slightly lower hardness than 6000 series coatings. |
Our Anodizing Process
Each anodizing order follows a controlled sequence from file upload through shipment.
- Quote and DFM review on uploaded Computer-Aided Design (CAD) files. Anodizing specification confirmed, dimensional compensation applied at CNC stage.
- Part preparation. Cleaning, etching, and desmutting for uniform oxide formation.
- Anodizing in a controlled bath to the target thickness and type specified on the order.
- Coloring and sealing where specified. Dye color matched to the approved sample or Pantone reference.
- Coating thickness verification by eddy current gauge and dimensional inspection.
- Packaging and shipment from Shenzhen or Florida facility.
Design Considerations for Anodizing
Specifying anodizing at the quote stage keeps tolerances accurate and finishes consistent across every part. The considerations below are the ones we review during every DFM check.
- Dimensional impact. Approximately 50% of the oxide layer penetrates inward and 50% builds outward. For Type II at 25 µm total thickness, expect roughly 12.5 µm of buildup per surface. We compensate at the CNC stage when anodizing is specified at quote.
- Masking. Threaded holes, mating surfaces, and electrical contact pads require masking before the part enters the bath. Specify masked areas on the drawing.
- Rack marks. Parts are suspended from contact points during anodizing, and these points will show as uncoated spots. Specify preferred rack locations on your drawing to keep marks off cosmetic surfaces.
- Corner radii. Minimum 0.5 mm internal radius recommended. External edges benefit from a 0.2 mm edge break before anodizing. This prevents coating buildup and chipping at sharp corners.
- Surface prep. Anodizing faithfully reproduces the surface it receives, including machining marks. For uniform cosmetic finishes, specify bead blasting or tumbling before anodizing. We run both operations in the same production line.
Acabado superficial
ESPECIFICACIÓN
Anodizado
Anodizing builds a hard oxide layer on aluminum surfaces. It improves corrosion resistance and allows color dyeing without paint. Available in Type II and Type III hard anodize up to 50 μm thickness.
Recubrimiento en polvo
Electrostatic powder coating delivers a durable, even finish in any RAL color. Coating thickness ranges from 60 to 120 μm. It resists chipping, scratching, and UV fading better than wet paint.
Revestimiento
Cepillado
Mechanical brushing creates a uniform satin grain on stainless steel and aluminum. It removes surface imperfections and produces a professional, non-reflective appearance.
Pulido
Multi-stage polishing achieves mirror finishes down to Ra 0.05 μm. Common on stainless steel parts for medical, food processing, and optical applications.
Pasivación
Why Choose Yijin Solution for Anodizing
We control every step of the anodizing workflow from DFM review through coating verification and shipment. That integrated approach means consistent oxide quality, accurate dimensional compensation, and certifications that meet aerospace, medical, and automotive requirements.
Every anodized order is verified by eddy current gauge for coating thickness and inspected dimensionally using Zeiss CMMs. Coating conformance is documented per MIL-A-8625. ISO 9001, AS9100D, ISO 13485, and IATF 16949 certifications are held across our quality system.
Anodizing is scheduled into the production run at the quote stage, not added afterward. Parts move from manufacturing to surface prep to anodizing bath to inspection in one continuous workflow, keeping lead times tight.
We anodize single prototypes and production runs of 10,000+ parts through the same controlled process and quality system. There is no minimum order quantity, and volume does not change the inspection standard.
Prototype and production parts are anodized in the same facility using the same bath chemistry and process controls. The specification validated on your first sample applies directly to your production run.
We anodize 6000, 7000, 2000, and 5000 series aluminum alloys, with process parameters adjusted per alloy family. Alloy-specific behavior, expected color response, and any finish limitations are reviewed during the DFM check before production begins.
Integrating anodizing with upstream CNC machining and fabrication in one facility removes the logistics cost of a separate finishing vendor. Our DFM review also identifies dimensional compensation requirements early, so parts are machined to the correct pre-coat dimensions from the first run.
Gallery of Anodized Parts
Below are representative anodized parts produced across aerospace, automotive, medical, robotics, and consumer electronics applications.
Battery pack enclosures, inverter housings, and solar mounting frames with powder coating or galvanizing for outdoor durability and fatigue resistance.
Marine-grade stainless steel control cabinets, bulkhead panels, and deck enclosures with salt spray-resistant finishes for vessels and port equipment.
AS9100D-certified avionics enclosures, structural panels, mounting plates, and access covers with full material traceability and First Article Inspection.
Brackets, battery enclosures, structural reinforcements, and dashboard frames produced under IATF 16949 with PPAP Level 3 documentation.
Appliance housings, consumer electronics enclosures, and decorative cabinets with brushed, anodized, or powder-coated finishes.
Instrument housings, sterilization trays, and medical cart panels in stainless steel with electropolished or passivated surfaces under ISO 13485.
Cleanroom enclosures, wafer handling panels, and vacuum chamber components in electropolished stainless steel for low particulate generation.
Machine guards, chip trays, tooling racks, and coolant enclosures for injection mold shops and tool rooms.
Equipment cabinets, deployable panels, and ruggedized electronic enclosures to MIL-SPEC and NAS standards with full documentation.
FAQs on Anodizing Services
Common questions about specification, color, dimensional impact, and documentation are answered below.
What is the difference between Type II and Type III anodizing?
Type II sulfuric acid anodizing produces a 5 to 25 µm oxide layer suited for general corrosion protection and decorative color. Type III hard coat anodizing builds a 25 to 100 µm layer at 400 to 600 HV. Type III targets wear surfaces, sliding mechanisms, and high-abrasion environments.
Can you anodize parts that were not machined by Yijin?
Yes, we accept parts from external suppliers for anodizing as an add-on finishing service. We recommend supplying a drawing with alloy grade, target anodizing type, and any masking requirements. This allows us to confirm the specification before processing.
What colors are available for anodized parts?
Type II anodizing supports clear, black, red, blue, gold, and custom Pantone-matched colors. Type III hard coat is limited to natural dark gray and black. Color consistency depends on alloy grade and surface preparation.
How much do anodized parts change in dimension after coating?
Approximately 50% of the oxide layer builds outward from the original surface. For a 25 µm Type II coating, expect roughly 12.5 µm of dimensional growth per side. We apply compensation at the CNC machining stage when anodizing is specified at quote.
Do you offer MIL-A-8625 conformance documentation?
Yes, we provide coating thickness reports and MIL-A-8625 conformance documentation with every order that specifies military or aerospace anodizing requirements.
Can you anodize cast aluminum parts (A356, A380)?
Cast alloys with high silicon content, such as A380, produce uneven oxide layers and inconsistent color. A356 responds better but still requires process adjustments. We review castability and finish expectations during the DFM check and advise on the expected result before production.
Surface Finish Guides
What is Passivation of Stainless Steel?
Stainless steel can still rust if its surface is not clean enough. During machining, grinding, tumbling, or handling, small iron
What is Bead Blasting?
Engineers often need a part that looks clean and even, without the shine or tool marks left by machining. Which
What is Electroplating?
Electroplating is often used when the surface of a part needs to do more than the base material can handle.
Request an Anodizing Quote
Anodizing specification is confirmed at the quote stage, dimensional compensation is applied at CNC, and coating is verified before shipment. Every order includes DFM review and MIL-A-8625 conformance documentation where required. Póngase en contacto con nosotros with your CAD files to receive a quote with anodizing specification recommendations within two business days.