# Absorptivity and emissivity of metal and deposited coating on metals

 MATERIAL Solar Normal Total Absorptivityαn, solar Total Hemispherical Emissivity at Moderate Temperature ε $\left( \frac{{{\alpha }_{n,solar}}}{\varepsilon } \right)$ Aluminum, polished 0.10 0.018 * 5.6 Chromium, polished 0.415 0.08 5.2 CrOx on aluminum foil 0.964 0.023 42 Copper, polished 0.29 0.019 * 15 CuO on aluminum sheet 0.90 0.15 6.0 Gold, polished 0.19 0.018 * 11 Iron, polished 0.445 0.05 * 8.9 Nickel, polished 0.15 0.04 * 3.8 NiS+ZnS on steel 0.88 0.10 8.8 Nickel dendrites on stainless steel 0.99 0.26 3.8 Platinum, polished 0.307 0.050 * 6.1 Silver, polished 0.07 0.017 * 7 Stainless steel, 301 0.37 0.05 * 7.4 Titanium 0.63 0.134 * 4.7 Tungsten, polished 0.37 0.03 * 12 Zinc oxide on stainless steel 0.95 0.08 11.6 Steel

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