6Emissivity Table
METALS
Material | Emissivity (ε) |
Aluminum – pure highly polished plate . . . . . . . . . . . . . . . . . . . . . . . . 0.04 to 0.06 Aluminum – heavily oxidized . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.20 to 0.31 Aluminum – commercial sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.09 Brass – dull plate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.22 Brass – highly polished, 73.2% Cu, 26.7% Zn . . . . . . . . . . . . . . . . . . . . . . . . . 0.03 Chromium – polished. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.08 to 0.36 Copper – polished. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 Copper – heated at 600°C (1112°F) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.57 Gold – pure, highly polished or liquid. . . . . . . . . . . . . . . . . . . . . . . . . 0.02 to 0.04 Iron and steel (excluding stainless) – polished iron . . . . . . . . . . . . . . . . 0.14 to 0.38 Iron and steel (excluding stainless) – polished cast iron. . . . . . . . . . . . . . . . . . . 0.21 Iron and steel (excluding stainless) – polished wrought iron . . . . . . . . . . . . . . . 0.28 Iron and steel (excluding stainless) – oxidized dull wrought iron . . . . . . . . . . . . 0.94 Iron and steel (excluding stainless) – rusted iron plate . . . . . . . . . . . . . . . . . . . 0.69 Iron and steel (excluding stainless) – polished steel. . . . . . . . . . . . . . . . . . . . . . 0.07
Iron and steel (excluding stainless) – polished steel oxidized at
600°C (1112°F). . . . . . . . . . . . . . . . . . . . 0.79 Iron and steel (excluding stainless) – rolled sheet steel . . . . . . . . . . . . . . . . . . . 0.66 Iron and steel (excluding stainless) – rough steel plate . . . . . . . . . . . . . 0.94 to 0.97 Lead – gray and oxidized . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.28 Mercury . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.09 to 0.12 Molybdenum filament . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.10 to 0.20 Nickel – polished . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.07 Nickel – oxidized at 649 to 1254°C (1200 to 2290°F) . . . . . . . . . . . . 0.59 to 0.86 Platinum – pure polished plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 to 0.10 Platinum – wire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.07 to 0.18 Silver – pure and polished . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.02 to 0.03 Stainless steel – polished . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.07 Stainless steel – Type 301 at 232 to 941°C (450 to 1725°F). . . . . . . . . 0.54 to 0.63 Tin – bright . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.06 Tungsten – filament . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.39 Zinc – polished commercial pure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.05 Zinc – galvanized sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.23
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