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Infrared
Emissivity |
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1 Emissivity table introductory comment
Understanding an object's emissivity, or its characteristic
"radiance" is a critical component in the proper handling
of infrared measurements. Concisely, emissivity is the ratio
of radiation emitted by a surface or blackbody and its theoretical
radiation predicted from Planck's law. [W(L,T)=C1/(L^5*(exp(C2/LT)-1)]
A material's surface emissivity is measured by the amount of
energy emitted when the surface is directly observed. There
are many variables that affect a specific object's emissivity,
such as the wavelength of interest, field of view, the geometric
shape of the blackbody, and temperature. However, for the purposes
and applications of the infrared thermometer user, a comprehensive
table showing the emissivity at corresponding temperatures of
various surfaces and objects is displayed. For a more detailed
and technical presentation of emissitivty, please contact ZyTemp
directly. |
 |
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Material
(Non Metal) |
|
|
 |
 |
 |
 |
 |
|
Material(Non-Metals) |
Temp degF(degC) |
Emissivity |
|
Adobe
|
68 (20)
|
0.9
|
|
Asbestos
|
|
贩
|
Board
|
100 (38)
|
0.96
|
|
贩
|
Cement
|
32-392 (0-200)
|
0.96
|
|
贩
|
Cement, Red
|
2500 (1371)
|
0.67
|
|
贩
|
Cement, White
|
2500 (1371)
|
0.65
|
|
贩
|
Cloth
|
199 (93)
|
0.9
|
|
贩
|
Paper
|
100-700 (38-371)
|
0.93
|
|
贩
|
Slate
|
68 (20)
|
0.97
|
|
贩
|
Asphalt, pavement
|
100 (38)
|
0.93
|
|
贩
|
Asphalt, tar paper
|
68 (20)
|
0.93
|
|
Basalt
|
68 (20)
|
0.72
|
|
Brick
|
|
贩
|
Red, rough
|
70 (21)
|
0.93
|
|
贩
|
Gault Cream
|
2500-5000 (1371-2760)
|
.26-.30
|
|
贩
|
Fire Clay
|
2500 (1371)
|
0.75
|
|
贩
|
Light Buff
|
1000 (538)
|
0.8
|
|
贩
|
Lime Clay
|
2500 (1371)
|
0.43
|
|
贩
|
Fire Brick
|
1832 (1000)
|
.75-.80
|
|
贩
|
Magnesite, Refractory
|
1832 (1000)
|
0.38
|
|
贩
|
Grey Brick
|
2012 (1100)
|
0.75
|
|
贩
|
Silica, Glazed
|
2000 (1093)
|
0.88
|
|
贩
|
Silica, Unglazed
|
2000 (1093)
|
0.8
|
|
贩
|
Sandlime
|
2500-5000 (1371-2760)
|
.59-.63
|
|
Carborundum
|
1850 (1010)
|
0.92
|
|
Ceramic
|
|
贩
|
Alumina on Inconel
|
800-2000 (427-1093)
|
.69-.45
|
|
贩
|
Earthenware, Glazed
|
70 (21)
|
0.9
|
|
贩
|
Earthenware, Matte
|
70 (21)
|
0.93
|
|
贩
|
Greens No. 5210-2C
|
200-750 (93-399)
|
.89-.82
|
|
贩
|
Coating No. C20A
|
200-750 (93-399)
|
.73-.67
|
|
贩
|
Porcelain
|
72 (22)
|
0.92
|
|
贩
|
White Al2O3
|
200 (93)
|
0.9
|
|
贩
|
Zirconia on Inconel
|
800-2000 (427-1093)
|
.62-.45
|
|
Clay
|
68 (20)
|
0.39
|
|
贩
|
Fired
|
158 (70)
|
0.91
|
|
贩
|
Shale
|
68 (20)
|
0.69
|
|
贩
|
Tiles, Light Red
|
2500-5000 (1371-2760)
|
.32-.34
|
|
贩
|
Tiles, Red
|
2500-5000 (1371-2760)
|
.40-.51
|
|
贩
|
Tiles,Dark Purple
|
2500-5000 (1371-2760)
|
0.78
|
|
Concrete
|
|
贩
|
Rough
|
32-2000 (0-1093)
|
0.94
|
|
贩
|
Tiles, Natural
|
2500-5000 (1371-2760)
|
.63-.62
|
|
贩
|
Brown
|
2500-5000 (1371-2760)
|
.87-.83
|
|
贩
|
Black
|
2500-5000 (1371-2760)
|
.94-.91
|
|
Cotton Cloth
|
68 (20)
|
0.77
|
|
Dolomite Lime
|
68 (20)
|
0.41
|
|
Emery Corundum
|
176 (80)
|
0.86
|
|
Glass
|
|
贩
|
Convex D
|
212 (100)
|
0.8
|
|
贩
|
Convex D
|
600 (316)
|
0.8
|
|
贩
|
Convex D
|
932 (500)
|
0.76
|
|
贩
|
Nonex
|
212 (100)
|
0.82
|
|
贩
|
Nonex
|
600 (316)
|
0.82
|
|
贩
|
Nonex
|
932 (500)
|
0.78
|
|
贩
|
Smooth
|
32-200(0-93)
|
.92-.94
|
|
Granite
|
70 (21)
|
0.45
|
|
Gravel
|
100 (38)
|
0.28
|
|
Gypsum
|
68 (20)
|
.80-.90
|
|
Ice, Smooth
|
32 (0)
|
0.97
|
|
Ice, Rough
|
32 (0)
|
0.98
|
|
Lacquer
|
|
贩
|
Black
|
200 (93)
|
0.96
|
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