Bands II/III low observable coatings
The Laboratoire de Physique et du
Rayonnement de la Lumière . (LPRL) provides
additives that give polyurethane paints simultaneously infrared low
observable characteristics in bands II and III. LPRL
also offers prepared polyurethane band II/III coatings that do not
compromise radar cross-section reduction schemes, are compatible with a variety of primers, and
may be applied using standard technology (e.g. spray gun).
LPRL’s lightweight coatings provide stealth
characteristics in bands II and III without significantly altering the thermal
exchange properties of the substrate or compromising radar stealth.
The emissivity e
of LPRL band II/III coatings may be tuned to meet the demands of the application, from a
minimum of 0.59 in band II (3 to 5 mm) or 0.75 in
band III (8 to 12
mm).
Some key characteristics LPRL’s band II/III coating are shown in the table below:
|
e
(band II) |
0.56
< e
< 0.62 |
|
e
(band III) |
0.72
< e
< 0.77 |
|
Maximum Temperature |
180 C / 356 F |
|
Min. Thickness |
50
mm / 2 |
|
Density |
1.3 |
|
0.013 |
Below is shown a thermograph taken with a bolometric infrared camera (a band III infrared camera) of an LPRL bi-band coating compared to a NATO black coating. The sample consisted of an aluminum plate which was heated on a hot plate to 60 degrees Celsius. The aluminum plate was coated with a NATO black coating,, which contains some aluminum powder to lower its emissivity. In the right hand region of the figure is an LPRL coating which was deposited over the black coating.
The apparent temperature is indicated for each region, and shows that the LPRL coating results in a reading 4 degrees Celsius (or 7 degrees Fahrenheit) below that of the black coating. From this image we estimate the emissivity in band III of the LPRL coating to be 0.72.
|
|
| [1] Assuming minimum thickness |
