Coating Tungsten Wire with Glass or Quartz

Xerox used to do this all the time for corona devices before the move to pin corona generators. One problem with any brittle coating on a wire is flex.

Osram Sylvania in Towanda, PA was the supplier of tungsten wire we used. I don't know if there is any IP still in force, but I'd call Osram and see what they know.

If you are looking chemical inertness, you could try: http://www.entechinst.com/silonite.php

Seems a pretty cool process.

It's just an excuse to wish you a very Happy Healthy and Prosperous New Year for 2007, but had you considered C.V.D. Diamond,

Check out:- http://cat.inist.fr/?aModele=afficheN&cpsidt=2688785

It's just an excuse to wish you a very Happy Healthy and Prosperous New Year for 2007, but had you considered C.V.D. Diamond,

Check out:- http://cat.inist.fr/?aModele=afficheN&cpsidt=2688785

Happy new year - this looks very interesting I will look it over - any further assistance would be highly appreciated.

Happy new year - this looks very interesting I will look it over - any further assistance would be highly appreciated.

Glad you found it useful, Google is great when you know what you are looking for. You may find the GEC Diamond Programme at Caswell interesting, They were developing high performance optical coatings, employing microwave plasma, way back in 1993. The GEC Journal of Research Vol 11 No1 1993 page 43, shows a scanning electron micro graph of a microwave plasma deposited synthetic diamond film, that revealed large square (100) facets at the surface, \fig.11., Fig.12 showed the diffraction trace, revealing a strongly oriented film in the <100> direction. For comparison a trace from a polycrystalline natural diamond was displayed below the CVD trace.

The morphology of the surface was found to be highly dependent on the growth conditions. As the application was for optical components, impurities which cause absorption of radiation and an optically scatter free flat surface were critical to the project. Your application may not be quite so demanding?

For simplicity and high mechanical strength, it's hard to beat the ubiquitous Oxy-Acetylene route. CVD films deposited this way were found, back then, to be superior, in this respect. For the short length you want to coat, I would guess that some sort of vibrating jig, holding the wire taut, and oscillating to and fro in a fine point jeweller's torch flame, might do the trick. The deposition rates are very slow, so occasional rotation of the filament/or flame might be desirable to deposit an even coating on all sides. Best of luck with your fascinating research.

Alastair.