LPPS Coating Temperature and 'Non-Stick' Coatings
I'm after some information and haven't been able to find what I need in a literature search so far, so I thought I'd ask here.
I'm asking about the temperatures experienced in an LPPS machine, in the plasma jet itself and in the atmosphere surrounding it.
It's a Metco 03CP plasma gun with an EPI 264A gas flow panel running on He and Ar. Metco 60C powder feed unit.
We typically spray revolving parts at a distance of approx. 12" from the nozzle exit. What I'm trying to find out is the temperature that might be experienced in the plasma jet 12" from the nozzle. Tough question!
I'd also like information regarding the temperature of the atmosphere in the coating chamber and perhaps the temperature gradient between the plasma jet and the inner wall of the chamber, although I can estimate this fairly easily once the plasma jet temperature is known.
It is quite clear that the jet would melt various superalloys if they were left in there stationary and the rate of melting is a function of time. What I want to determine is, based on the temperature of the jet, how long various alloys can be exposed to the plasma jet during both the TA cleanup process and coating process. Any pointers to answer this question would be greatly appreciated!
Another related question is about non-stick coatings, such as Teflon variants, that we could apply to tooling to prevent the adhesion of MCrAlY and reduce the need for acid stripping the tooling. This is directly related to the temperature related in the plasma jet area, or rather the temperature that the tooling might reach after x amount of time. If anyone has any advice or experience that they could share regarding non-stick coatings in high temperature environments, ideally with MCrAlY involved, then I'd appreciate that too.
Thanks!
Rich
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