SpectralEmissivity & Emittance

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High-Temperature Spectral Emittance of Oxides of Erbium, Samarium, Neodymium and Ytterbium

Author: Guazzoni, Guido E.1

Source: Applied Spectroscopy, Volume 26, Issue 1, Pages 1-113 (January/February 1972) , pp. 60-65(6)

Publisher: Society for Applied Spectroscopy

Abstract: Normal spectral emittance data are reported for solid specimens of the oxides of erbium, samarium, neodymium, and ytterbium… over the spectral range ..0.5-5.0 um and at sample temperatures from 1540 up to 1870 K.

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Spectral Emittance of Ablation Chars, Carbon, and Zirconia to 3700 deg K

Hemispherical Spectral Emittance of Ablation Chars, Carbon, and Zirconia to 3700 deg K

Abstract: The initial results of the application of special optical techniques to high-temperature emittance and reflectance studies of an ablation-material char and certain other refractory materials representative of those present in ablation residues formed during aerospace reentry operations are presented. Spectral hemispherical emittance and reflectance were determined with an image pyrometer integrated with an arc-imaging furnace for carbon, graphite, zirconia, and a phenolic-nylon ablation-material char at wavelengths from 0.37 micrometer to 0.72 micrometer for temperatures from 2100 deg K to 3700 deg K. The data obtained are compared with those of other investigations to the extent that the existence of comparable data permits. Surface-roughness properties of the materials studied were determined from measurements made with a light-section microscope. The dependence of the spectral hemispherical emittance of oxidized carbon at a wavelength of 0.65 micrometer on its surface-roughness properties was investigated experimentally and the emittance was found to be a linear function of the root-mean-square slope of the surface when the roughness is large compared with wavelength. p3

Description: Technical note
Pages: 31
Report Date: MAR 65
Report Number: A107703

Normal Spectral Emittance Measurements (600–2000 nm) of Alumina

An online General Electric Company Downloadable Corporate R& D Technical Report (PDF Format – 308KB)
Report Title: Normal Spectral Emittance Measurements (600–2000 nm) of Polycrystalline Alumina (PCA) at High Temperatures

Author(s) L. Bigio, of the Component Ceramics Laboratory
GE Report Number: 99CRD128

Date: November 1999
Number of Pages: 8

Key Words: spectral emittance, 600-2000 nm, polycrystalline alumina, PCA, high temperatures, fiber optic radiance probe

“A novel method is shown for measuring the spectral emittance of polycrystalline alumina (PCA) in the temperature range ~1100-1400 C, from 600-2000 nm. The method utilizes a CO2 laser at 10.6 microns to heat a ~4 mm size spot on a small sample (~6×4 mm) from one side, while the temperature and emission are measured optically from the other side. A fiber optic radiance probe focuses on a 2 mm spot in the middle of the larger heated region, and directs the collected emission to a spectrometersystem. Radiance measurements are conducted relative to a blackbody at 1000 C. The temperature is measured at the same location viewed by the radiance probe using a thermal imaging pyrometer with a narrow bandpass at 10.6 microns. Since this is the same wavelength as the laser, care must be taken to avoid the scattered laser radiation that partially overfills the sample. An emittance at 10.6 microns of 0.97 is assumed for the temperature measurements. In this spectral region, the emittance is found to decrease with increasing wavelength and increase with increasing temperature. This method can be used on other ceramic materials as well.”

Emissivity and Optical Properties of UO(2)

Emissivity and Optical Properties of UO2

Tabulated Values: