Chemical Film vs. Anodize

It’s been a while since we’ve posted, so we figured we would give you a post relative to what we have seen recently in manufacturing. For some reason, we have been seeing a lot of engineers who are calling out the incorrect finish for their parts, and we want to help set the issue straight! Simply put, chemical film (also known as┬áchromate conversion, yellow iridite, or alodine) and anodize are NOT the same thing. Most people assume that they may have similarities, that they can be used interchangeably, but this is not the case for most instances. So let’s take a close look at what each finish is and when you should use them. But first, I’d like to point out and say that although we are a metal fabricator, we actually have an in-house metal finishing shop as well as a sister metal finishing company, and have knowledge on when and when not to use each of these finishes. Continue reading

Anodize Coatings for Aluminum Alloys

purple anodize aluminum partMore recently, we have been seeing manufacturing prints that call-out an incorrect military spec for anodize on aluminum parts. As a result, we wanted to do this blog post to better inform engineers of calling-out the right classifications for anodize. But first, here is a mistake we have recently seen that is a good example:

Incorrect: “Finish: Anodize MIL-A-8625 Type II, Class 1, Blue”

The issue with this incorrect call-out is the class number and color. According to Military Spec MIL-A-8625, Class 1 is designated as “non-dyed.” This contradicts the “blue” color that is called out. All Class 1 specifications need to be clear color. To designate a color (blue, black, etc.), Class 2 needs to be specified. Here is the proper way to call out the specification above (please note the following call-outs are an example pertaining to the incorrect call-out above. Call-outs can vary depending on the desired Type/Class/Color): Continue reading