
Posted by Juergen (217.6.15.137) on 12:54:43 08/09/05
In Reply to:H2 instead of He for Al2O3 spraying posted by Régis Pittier
: Hi,
:
: This is a quite simple question, I guess, but I'm pretty new to surface coating...
:
: I'm currently working with a Triplex plasma spray to coat Al plates with Al2O3/TiO2 ceramics. I'm using Ar as primary gaz and He as secondary. I'd really like to get rid of He, and I've thought about using H2 instead. I know this is a vast topic, so I would appreciate you mention some readings or webs site I should look at in order to understand how to do it and what kind of results I should expect.
:
: Please let me know of any similar experience you've been through.
:
: THX
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Tis is Juergen again,
as I wrote yesterday we´re working with the triplex plasma gun.
I got in touch with a developer of this gun. He told me, that H2 or N2 or othe molecular gases would destroy the anode of the Triplex gun because the current densitiy will become too high locally at the 3 contact zones of the anode, resulting in melting it.
So, please use only He as secondary gas.
Regards
Juergen
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