Is Matte White Anodizing possible?

A. Yes, White Anodizing is possible. The color is opaque white ceramic coating that is harder than Hard Anodizing. The problem with this coating is that unlike conventional Hard Anodizing, the coating is not self sealing, and white color cannot be preserved if sealed in any of the commercially available sealing solutions. The way to overcome this problem is to avoid aqueous hydrated solutions, since even small amounts of water will turn this coating into gray color. If the color is not objectionable, Sealing this coating in conventional Nickel Acetate Solution will result in glossy gray finish. Silvery white coatings are much easier to obtain, consult your vendors.

A. Hello Mark. Forget Type I. My gut feel is that no anodized aluminum finish will give you quite the look you seek, but Type 2 is certainly best. It can be left uncolored (aluminum color, not white) or it can be dyed (almost any color except white). If you look around you can find examples to work with to get a feel for what it's like (aluminum clothes hangers, knitting needles, crochet hooks, archery arrows, paintball guns, flashlights). Type 3 hard coat will probably not be reflective but matte in appearance and probably light gray to not quite black. Sorry, I can't offer pricing estimates except to say that anodizing is not a particularly expensive process.

A. You can achieve and almost white appearance on a type 2 anodized surface with the correct surface preparation is key. I can get my type II to an off white color but it still does have a shade to it.

A. I will be happy to. I have achieved an "Off-White" coating coloration on type 2 anodizing by preparing the surface with Glass bead blasting. and then with my type 2 bath at 175-180g/l and at a temp of 70 degrees. I can plate to a thickness of 2.5 - 3.5 tenths this results in an off white appearance of the aluminum. If you plate over 3.5 tenths the coating becomes more greyish off-white. Now keep in mind that I use a caustic etch and I etch commonly 2-3.5 minutes @ 120 degrees after a 10 minute soak clean at 140 degrees. as well as a Ni-acetate seal to end it all up. I can send photos if you would like.

A. I use roughly 14.5 to 15 amps per square foot.

It is a lower ASF than normal and yes it allows the pore size to be larger. That is my guess.. But it comes out an off white color.

A. Hi Milt. Per this thread, and related thread 11600, it seems the answer is "close but no cigar".

A. Some years back a large finishing company that I worked for in the Springfield, Massachusetts area developed a very nearly white anodize. I'm not sure if they still offer it on a small run, custom basis. Large runs were definitely out of the question.

A. Hi, Ivan. Another thread which talks about white anodizing is 11600; it presents a 23-page pdf about a white anodizing method. Please try to describe your situation (are you a consumer/product designer/OEM, or an anodizing shop employee?), what kind of components (rivets, extrusions, castings, machine parts, RVs), the environmental exposure (interior/exterior use?). If you are able to frame your question in terms of the answers that were provided I'm confident that people will be able to help you with it. Good luck.

Regards,

A. To the best of my knowledge, conventional anodizing dyes are still not available in white. I do recall that some company has claimed to develop electrolytic coloring process that is white, but I've never seen it.

A. 1. Threads should not be anodized because the sharp edges are completely converted to oxide which will flake off. No sharp edge should be anodized.

2. White dye for coloring anodic pores is not available.

A. Hi Lorenzo. Are you sure that you mean "anodized" -- because that implies that the allen screws are made of aluminum, whereas aluminum is an unusual material for allen screws. Whether the screws are aluminum or zinc plated steel, you might consider electrophoretic lacquer, as it is both thin and less likely to chip off than most organic coatings.

Regards,