20. Emissivity
Emissivity characterization reflects the of material's radiated energy. Emissivity for most organic materials,
paints or oxidized surfaces are about 0.95. Total emissivity of selected metals and non-metals are listed in the
following table.
Measured surfaces
Metal
Aluminum
Oxidization
Oxidization
A3003 Alloy
Rough
Burnishing
Brass
Oxidization
Oxidization
Copper
Electric terminal board
Hastelloy
Alloy
Oxidization
Inconel
Sand-blasting
Electro burnishing
Oxidization
Iron
Rusting
Oxidization
Iron (casting)
Non-oxidization
Casting
Iron (forging) Passivation
Rough
Lead
Oxidization
Molybdenum Oxidization
Nickel
Oxidization
Platinum
Black
Cold rolling
Steel
Steel plate burnishing
Steel plate rubbing
Zinc
Oxidization
Emissivity
0.2-0.4
Asbestos
0.3
Asphalt
0.1-0.3
Basalt
0.3
0.5
Carbon
0.4-0.8
0.6
Ceramics
0.3-0.8
Clay
0.7-0.95
Concrete
0.3-0.6
Cloth
0.15
0.5-0.9
Glass
0.5-0.7
0.6-0.95
Plates
0.2
Stone products
0.2-0.3
Plaster
0.9
Ice
0.4
Limestone
0.2-0.6
Paper
0.2-0.6
Plastics
0.2-0.5
Water
0.9
Soil
Wood
0.7-0.9
0.4-0.6
0.1
0.1
9
Measured surfaces
Non-metal
Non-oxidization
Graphite
Silicon carbide
Convex glass
Smooth glass
Lead-boron glass
English
GB
Emissivity
0.95
0.95
0.7
0.8-0.9
0.7-0.8
0.9
0.95
0.95
0.95
0.9
0.76-0.8
0.92-0.94
0.78-0.82
0.96
0.93
0.8-0.95
0.98
0.98
0.95
0.95
0.93
0.9-0.98
0.9-0.95