Abstract
The spectral emissivity ε(λ, T) is required when thermal radiation pyrometers are used to determine the true temperature of a subject. If the surfaces of steels are heated in air, the values of ε(λ, T) changes in dependence on the oxidized condition of the surfaces. However, oxidizing conditions have not been exactly controlled in studies on the spectral emissivity of oxidized surfaces of steels. So, reported values of ε(λ, T) are rather unreliable and sometimes unavailable.
In the present study, the values of ε(λ, T) on the surfaces of commercial steels, that is, JIS S09CK, SUS430, SUS304, and SKH3, which were heated in controlled atmospheres of different oxygen partial pressures, were measured at temperatures from 1000°C to 1300°C and in the wavelength region from 0.34 to 0.94 μm.
Experimental results were examined by the equation concerning to free electrons and the lattice vibration and constants which are used to calculate the values of ε(λ, T) were determined.
