FINISHING SERVICES

Chem Film

ISO 9001: 2015 Certified

Real-Time Traceability

Machining & Finishing

Simplified Sourcing

Chem Film for Prototyping
and Production

Chem Film Standards

MIL-DTL-5541 (Type 1)

MIL-DTL-5541 (Type 2)

AMS-2473

AMS-2474

What is Chem Film?

Chem Film, aka, Alodine™ or Chromate Conversion Coating, is a chemical treatment applied to for aesthetic reasons and to protect metals from corrosion. Alodine™ is a trademark of Henkel Surface Technology and is also known by other names such as Iridite Coating and Yellow Iridate.

Application Methods: Chem Film can be applied to metals by dipping, spraying, or brushing.

Benefits of Chem Film:

Improved paint adhesion

Corrosion protection

Increased electrical conductivity

How does it work?

During a Chem Film coating process, chromate ions (hexavalent or non-hexavalent) act as oxidizing agents to create a passive layer that bonds to the metal surface. This protective, enhanced oxide layer improves corrosion resistance and adhesion for paints or primers. It may also be utilized to modify the aesthetics of a part.

Chem film or Alodine™ is a proper corrosion resistant aluminum surface treatment for painting, powder coating, adhesive bonding, heat sinks, and automotive wheels.

Applications: Often used in the automotive industry on bumpers, grilles, and other car exterior parts, as well as precision machining parts in the manufacturing industry.

Dependable Chem Film Quality
to Unblock Innovation

Production-Grade Quality Inspection of Finished Surfaces

On-Demand Inspection Reports

95.4%

Perfect order success rate

(on-time, in-full delivery)

Get Instant Quote

Masking for Chem Film

Your parts may require masking if you have tight tolerances on your threads or holes. This may even be applicable for a thinner, type II Mil-DTL-5541 coating. Masking may be accomplished with plastic plugs, tape, or even painted liquid plastics. Masking should be called out on a drawing with notes. If you have questions about masking or plugging, contact one of our experts today.

Color Variation with Chem Film

The simplest way to evaluate a conversion coating is to observe a continuity in appearance, smoothness, and adhesion to the base metal. Visual examination is performed to ensure that proper cleaning and coating procedures are used so a coating with sufficient protection exists over the entire part., Materials qualified per MIL-DTL-5541 produce coatings that range in color from clear/colorless to iridescent yellow, brown, gray, or blue.

The following may impact color uniformity:

a. When several alloys are processed with the same conversion chemical, color may vary from alloy to alloy. This is due to the composition differences amongst alloys.
b. Due to the high level of impurities and oxidation on the surfaces of aluminum welds and castings, color may not be as uniform as it is in treating wrought alloys.
c. Conversion chemicals may drip and cause dark spots when the parts are lifted out of the treatment tank. A small amount of spotting is generally acceptable but can be minimized by rinsing after treatment and using proper racking techniques.

Visual examination does not reveal if the protective value of the coating has been impaired by contamination or by overheating during drying. If a clear coating is required, inspection difficulties may arise because visual inspection does not reveal the presence of a coating.

Let’s build something great, together

Get a quote now

Learn More about CNC Machining

CNC Machining design guide

Rapid CNC Machining vs. Traditional CNC Machining
Read More >

PRECISION MACHINED PARTS

Precision Machined Parts: Fictiv's Comprehensive Guide
Read More >

TIPS FOR REDUCING CNC LEAD TIMES

Top 10 Design Tips for Reducing CNC Lead Time
Read More >

YOU MIGHT ALSO BE INTERESTED IN

First Article Inspection (FAI): The Guide for Engineers and Manufacturers

In manufacturing, quality control is engineered and measured. Before production launch, you need proof that your design can be built repeatedly as intended. That data comes from a verification process called First Article Inspection (FAI). During product development, engineers put considerable effort into ensuring the design is near perfect—from dialing in dimensions and tolerances to […]

Learn More

How On-Demand CNC Manufacturing Accelerates New Product Introduction (NPI)

As manufacturers across the U.S. and Canada bring production closer to home, the fastest teams are winning launch windows. Compressing the “design → make → test” cycle isn’t just about efficiency—it’s now a core competitive advantage. On-demand CNC machining, by intelligently routing precision parts to pre-vetted suppliers across regions, enables faster prototyping and pilot production […]

Learn More