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Need a better water protective coating for Beryllium X-ray target disks

2003

Presently, we are coating the water side of our beryllium disc x-ray target using titanium over titanium nitride. This coating microcracks and corrosion/undercutting of the beryllium occurs through these cracks and any micropits.

The beryllium gets hot due to electron beam bombardment of the other side of the 10" diameter disc. Additionally, the disc flexes due to the difference in pressure between the water system and vacuum. Lastly, the disc flexes due to the differential expansion during electron bombardment.

I'm afraid that the titanium is unable to flex and reflex without cracking. We are considering chromate conversion and perhaps anodizing. Does anyone have any experience with this?

Thanks.

Nick L [last name deleted for privacy by Editor]
Medical X-ray equipment - Los Gatos, California, USA

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The item can be soft gold plated or sulphamate nickel plated, which should be quite flexible. I believe it can be successfully chromate conversion coated. I think, but don't know, that an anodized coating would lack flexibility and be too brittle. Good luck..

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