(09-19-2011, 07:47 PM)djewell Wrote: Is anyone aware of a thermal barrier coating material which can be sprayed via a high velocity process? I am looking for something like aluminum oxide in a NiCr matrix.
Hi djewell,
I want to share that Aluminum Oxide and combination of Al2O3 + TiO2 coatings can be done very very easily on Detonation Spray Process which is high velocity process and i think this gun only can do ceramic coatings in High Velocity process family (which is not at all possible with HVOF process because of low heat input).
Regarding Thermal barrier coating, YSZ coatings with Plasma Spray Process (Yitria stabilized zirconia (or) Magnesia stabilized zirconia coating) is best suitable coating if you are looking for thermal barrier properties and please note that Magnesia stabilized Zirconia coating can be done with Powder Flame spray process also.
Because of any limitation if you want to coat Al2O3 for thermal barrier applications, then why u are selecting Nicr matrix because NiCr is very conductive then how u will get thermal barrier properties?
I also want to say that doing thermal barrier coatings with High velocity processes is also not a good idea because in high velocity processes porosity is very very low, because of that effect of thermal barrier properties will be reduced but you can get good bond strength if you coat with high velocity processes.
Regards,
SREENIVAS