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Aluminum (or Metallic) Coating

I am trying to find an inexpensive way to coat a diffractive surface. I have tried plating the surface with chrome and nickel, however, the plating has become a problem because of the feature size. I want to try using a metallic coating such as aluminum. However, I cannot find a inexpensive (in comparison to plating) method for high production; the optical industry provides coating for a high price. I have heard of trying "coaters" from the jewelry industry or toy industry. I would like some recommendations on who can provide this service for me with the following parameters: low cost, high throughput, and controllable coating thicknesses.

Julie Kiggins
1998

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I can't imagine how small your parts must be if plating is a problem. Feature size is molecular when it comes to plating.

Perhaps a description of the problems will draw some suggestions.

  
Tom Pullizzi
Falls Township, Pennsylvania
1998

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1997

Alumiplate located just north of the Minneapolis-St. Paul area in Minnesota plates aluminum onto metallic surfaces out of an organic solvent bath. The process is commercialized with facility for high volume work loads.

They have started working with clients in the optics industry for supply of aluminum coatings which take a high degree of polish.

William De La Torre

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Julie,

My company builds a sputter deposition system for high volume low cost plating. The system is an outgrowth of sputter deposition systems we built for CD's. We have used the system for plating of aluminum, titanium and chrome.

Achieving a high polish is primarily a function of the substrate's surface. All of our work has been done on plastic parts produced in highly polished molds. A dazzling finish is possible. Metal, glass and even certain rubbers can be sputter coated in addition to plastics.

If you can give me more information regarding the size of the parts, the material and volumes, I could be of more help.

Best Regards,

Paul Gelardi
- E Media
1998

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I may be in the wrong place here. I am looking for a contact that can coat aluminium onto plastic (for bags).

Is it achievable ? Is it really, really difficult ? (UK)

John Owens
- - Skills Applied
1998

Dear Mr. Owens,

I assume you do not want to coat a finished bag. Aluminum coating on plastic or paper rolls for the packaging industry has been done for years, and many companies do that. Check with www.svc.org. Aluminum coating seals potato chips, etc. from moisture.

Mandar.

Mandar Sunthankar
- Fort Collins, Colorado
1998

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1998

I have a question, is there anyway possible to coat aluminum with something so a magnet will stick?

Thank you very much!

M .Cotter

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M.Cotter:

You can electroplate aluminum with iron, or other magnetic materials--it's not that difficult to do, industrially. Of course, depending on how much magnetic force you want, you may have to plate it with more thickness that you might like.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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Julie,

The most inexpensive way to deposit aluminum at high volume is by PVD processing. This process is used to coat all kinds of inexpensive articles such as jewlery, bottle caps, etc. A number of contract coaters can help you. This process is used to coat CD music discs and diffraction gratings so I am sure that you can get the conformal coating are looking for.

Donald M. Mattox
Society of Vacuum Coaters
Albuquerque, New Mexico 1998

It truly isn't a matter of feature size, Julie.

I was involved with a product something like you are describing: it was a technology to replace microfilming, which used clear mylar films and no chemical processing whatsoever. The 'black' areas of the microfilm (like letters and lines) were simply embossed with a diffraction grating that prevented light from passing through the clear mylar. We made the stampers via conventional two-part silvering of a master, followed by electroforming.

The point being that any of the technologies, from vacuum metallizing, to electroplating, to mirror silvering should handle your project just fine. But, as Don said, CD manufacturers have gone to PVD coating the master, rather than two-part silvering it, prior to electroforming.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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I may be not right here but whether anybody can guide me or tell the process of chrome vapour deposition on glass with fine pitch or grating application is optoelectronics even sourcing of the same would be of great help to me.

suhas joshi
- India
1998

Suhas, you may contact Nitant Mate at EcoSolar, Ltd. in PUNE, and check if he would be interested in vacuum coating chrome for you. If the application is for very thin uniform coatings, you may need to use sputtering.

Mandar Sunthankar
- Fort Collins, Colorado
1998

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I'm conducting a research about a company which makes PVD coatings, and I'm looking for any potencial costumers who would like to buy the equipment, if you have any information I would appreciate it a lot! THANKS!

Gador Garza
1998

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I need help to find out the way for the diffusion of Aluminum into mild steel by heating in aluminum powder in way to obtain a resistant aluminum-iron alloy over the surface of mild steel.

If you have some advise or maybe a company that can help on this I will appreciate it very much.

Benjamin Sierra
- Monterrey, Mexico
1999