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Corrosion Resistant Light Absorber (Selenium Atmosphere)

Hello!

In a reaction chamber I want to heat a small glass substrate by a radiation heater (3000 K color temperature). For temperature homogeneity and light absorption I want to mount the substrate on a highly conductive absorber plate. The natural choice for material would be copper, but:

1. The substrate shall be heated to 850 K at > 20 K/s, therefore I need the best possible absorption -> blackening finish that can stand thermal stress?
2. The chamber will work in vacuum (-> no outgassing surfaces) as well as in selenium atmosphere. Selenium is highly corrosive for copper (and nearly any other material, best would be molybdenum or ceramics)! -> Surface finish should be corrosion resistant.

The choice of copper as absorber material was my first idea, another possibility would perhaps be Aluminium nitride. Any idea on blackening of AlN? By the way: Aluminium can not be used, it reacts with Se and air humidity to highly toxic Selenium hydride.

Patrick B [last name deleted for privacy by Editor]
- Erlangen, Germany
2001

Hi Patrik. We are working on the same problem -- selenium resistant material -- and I am curious if you have any answer by now?

Alfred Spitzenberger
- Linz, Austria
March 16, 2009

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March 17, 2009

Hi, Alfred. Patrick's question is old, and I'm not sure why it did not attract some answers. Regardless, be assured that many people view this thread every month, and you can certainly be of help to them, and they will hopefully be of help to you. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Ted is available for instant help
or longer-term assistance.

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