Normal spectral emissivity measurement on five aeronautical alloys

Aeronautical alloys have a good performance on resisting oxidization, corrosion and fatigue in high temperature environments. Therefore, they are not only widely employed in aero-engine but also in nuclear and petroleum industries. The normal spectral emissivity of five alloys in the wavelength ranging 1–15  μm at moderate and high temperature (400–1200 K) is measured. It is found that the emissivity decreases with the increasing of wavelength and increases when temperature rises. The effects of oxidation and flame treatment process are also studied. The results of the oxidized samples indicate that oxidation can enhance the emissivity significantly and alter the wavelength dependent trend. The results of the flame treatment processed samples show that the impurities and defects caused by the flame treatment process moderately increase the emissivity. The experimental data presented in this paper can be used directly to improve the accuracy of radiation computation and other relevant applications.