Plasma White Alumina
A&A Coatings material is a white alumina ceramic powder for plasma spray. It produces dense coatings which resist wear by fibers and threads, and also resist erosion in high temperatures. These coatings are also useful as thermal barriers and, when sealed, are used for electrical resistance in high temperatures.
Material Powder Characteristics
| Typical Composition: | Aluminum Oxide (98.5%) Silicon Dioxide (1%) Other Oxides (Balance) |
| Typical Size Range: | -270 mesh +15 microns -53 +15 microns |
| Melting Point: | 2000°C (3630°F) approximate |
Physical Properties of Coating
| Texture, as sprayed, (microinches RMS): | 325-400 |
| Finish, ground (microinches aa): | 45-50 |
| Macrohardness: | Rc60 |
| Cross-Sectional Hardness (DPH300): | 690 |
| Density (g/cc): | 3.3 |
| Coating Weight (lb/ft2/.001″): | .017 |
| Porosity | Low |
| Bonding: | Good |
| Emissivity: | 0.2-0.3 |
| Thermal Shock Resistance: | Very Good |
Thickness Limitation
A&A Coatings Plasma Sprayed White Alumina was designed for use in thin coatings, not more than .5mm (.020″) thick. If sprayed thicker, the probability of cracking and delamination will increase rapidly, as is the case of thick coatings of all fine powders.
Surface Preparation
A&A Coatings Plasma Sprayed White Alumina can be applied to most substrates which have been cleaned to remove surface oxides. This cleaning is accomplished with a light grit blast. Additionally, a “Bond coat” is required in most cases. Please contact us for substrate specific requirements.
Finishing
A&A Coatings Plasma Sprayed White Alumina can be ground to required finish size and polished to a 20 surface finish.