Abstract

The hemispherical emissivities of five transition elements, V, Nb, Ta, Mo, and W, have been measured from 300 to 1000 K, complementing earlier higher-temperature results. These low-temperature data, which are similar, are fitted to a Drude model in which the room-temperature parameters have been obtained from optical measurements and the temperature dependence of the dc resistivity is used as input to calculate the temperature dependence of the emissivity. A frequency-dependent free-carrier relaxation rate is found to have a similar magnitude for all these elements. For temperatures larger than 1200 K the calculated emissivity is always greater than the measured value, indicating that the high-temperature interband features of transition elements are much weaker than those determined from room-temperature measurements.

© 1987 Optical Society of America

Thermal radiation from metal surfaces

A. J. Sievers
J. Opt. Soc. Am. 68(11) 1505-1516 (1978)

Total hemispherical emissivity of tungsten

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The total hemispherical emissivity of copper

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Temperature variation of total hemispherical emissivity of stainless steel AISI 304

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