Sulfuric acid alumite is the most common anodic oxide coating.
The clear coating gives the product a beautiful appearance while maintaining the texture of aluminum, along with a hard surface and high corrosion resistance.
It also allows colorful dyeing of products.

Compliance standards (examples)
MIL-PRF-8625F (MIL-A-8625) Type II Class 1 (Non-dyed)
MIL-PRF-8625F (MIL-A-8625) (Dyed)
SAE-AMS 2471
SAE-AMS 2472
Sealing: We offer dichromate (Na), nickel acetate, hot water, high-pressure steam sealings and others according to the product’s specifications.

Sulfuric acid anodizing
Standard coating thickness: 10μm or greater
Maximum coating thickness: 30μm
(Reference: In JIS H 8601, coating thickness is classified into 7 grades: AAs3, 5, 6, 10, 15, 20 and 25)
(Reference: In ISO7599, coating thickness is classified into 5 grades: AAs5, 10, 15, 20 and 25)

Maximum product size for processing

◆Second line: 350×1,700×9,000mm

Maximum weight for processing depends on the product size and shape.

◆Fourth line: 1,000×1,100×2,800mm (500×1,100×2,800mm for black oxide finish)

We can normally handle product masses up to 800 kg.
(We will do our best to handle products with larger masses.)

◆Sixth line

A large alumite production line for the 8th-generation liquid crystal manufacturing equipment
Compatible with large panels sized 3,000 × 4,000 mm with a maximum weight of 1 t

At our company, the standard coating thickness is set to 10μm unless specified.
You might think that alumite has only to remain on a product surface.
Please be sure to include the quality level of anodic oxide coating in your product quality plan.
We deliver the planned quality.

Welcome to the authentic hard alumite.
You might think that hard alumite is just a thick alumite.
Merely increasing the thickness of alumite never creates hard alumite.

At the Riken Alumite Industry, we offer technically-established hard alumite treated in a cold electrolytic bath.
Our know-how sufficiently accumulated so far will surely satisfy your needs.

Compliant with MIL-PRF-8625F (MIL-A-8625) Type III Class 1 (Non-dyed) Class 2 (Dyed)
SAE-AMS 2469 and other specifications In general, sealing treatment is not applied because it reduces abrasion resistance.
Even though, we will apply sealing treatment such as dichromate (Na), nickel acetate, hot water, and steam sealings upon your request.

We also accept copper-containing alloys (A2024, A2017, etc.).

Available sizes and masses

1,400×1,100×2,800mm (500×1,100×2,800mm for black oxide finish)
We accept products with a weight of up to 800kg regularly.
(We will accept products heavier than 800kg as much as possible.)
We have prepared other production lines that can treat products with a size of up to 350×1,500×9,000mm.

Chromic acid alumite is a thin and dense coating with high corrosion resistance.
Anodic oxide coatings generally reduce the fatigue strength of a base metal, but chromic acid anodic coating has a negligible impact on metal fatigue strength. Chromic acid anodic coating has therefore been applied to aircraft fuselage, structural materials and components.
In addition, the chromic acid in the electrolyte acts as a corrosion inhibitor and will not dissolve or corrode if left on the product, so it can be safely used on products whose structure is prone to electrolyte residue, such as assembly components.

Conforms to MIL-PRF-8625F (MIL-A-8625) Type I Class 1 (non-staining) Class 2 (staining)
MIL-PRF-8625F (MIL-A-8625) Type IB Class 1 (non-staining) Class 2 (staining)
SAE-AMS 2470 and other specifications
Sealing: We offer dichromate (Na), nickel acetate, deionized water sealings and others depending on the product’s specifications.

Available sizes and masses

800×1,800×2,100mm (500×1,100×2,100mm for black oxide finish)
We can normally handle masses up to 800 kg. (We will do our best to handle products with larger masses.)

Meets MIL-DTL-5541F Type I Class 1A/MIL-C-5541E Class 1A
(Iridite 14-2, Alodine 1200)
Meets MIL-DTL-5541F Type I Class 3/MIL-C-5541E Class 3
(Iridite 14-2, Alodine 1000)

Compliant with other aeronautical standards.

Generally applied for anti-rust treatment and painting surface preparation treatment.
Proves effective where electrical conductivity and corrosion resistance are required.

Colored chromate: Iridite 14-2, Alodine 1200
Colorless chromate: Alodine 1000

Maximum size for processing (for Iridite 14-2)

900×1,300×2,000mm

*Iridite 14-2 is QPL-81706 approved, and Alodine is Ministry of Defense approved.

*We will accept products with a size larger than the above as much as possible.

Alodine 1000 is applicable to products with a size of up to 900×1300×2000mm.
Alodine 1200 is applicable to products with a size of up to 500×650×650mm.

Newly prepared large-scale processing line
Size of the treatment bath: 950×1,500×7,500mm
Alodine 1000 and Alodine 1200 treatments are available.
Large components are also acceptable.
Please contact our sales engineering department.

Oxalic acid anodizing

Standard coating thicknesses of oxalic acid alumite are 6μm and 9μm.
Since its integral gold color, oxalic acid alumite is usable as a colored anodic coating.
Unlike dyeing, oxalic acid alumite causes no decolorization. Oxalic acid alumite also provides excellent corrosion resistance and reliable gloss.

“Alumite” is originally a trade name for the oxalic acid anodic oxide coating.
It is a high-quality anodic coating invented in Japan, although only a few domestic processors still process true “ALUMITE.”
Corrosion resistance of oxalic acid alumite is reported to be superior to that of hard alumite.

Available sizes and masses

Please contact our sales staff for the size and weight processable.

Industrial (hard) chromium plating is the most reliable surface treatment to prevent sliding wear. The coating is very hard and excellent in abrasion, heat and corrosion resistances.

Hardness: 800HV or higher (JIS H8615 specifies 750HV or higher)
Friction coefficient (guide): static friction coefficient of 0.17, dynamic friction coefficient of 0.16

This anodic coating is produced by anodization in a phosphoric acid bath and can be used as a base treatment for plating of aluminum or as a base treatment for painting and bonding.
Unlike other anodic oxide coatings, hydration sealing treatment is inapplicable to the coating. However, since the coating adsorbs no crystal water, stable adhesion effect can be expected.

Available sizes and masses

Applicable to products with a size of up to 400×500×400mm.

Acid etching with a mixture of sulfuric acid and dichromate enhances adhesion strength.

Available sizes and masses

Applicable to products with a size of up to 800×1,500mm×2,000 mm. *We will accept products with a size larger than those mentioned above as much as possible.