Experimental research on the spectral emissivity measurement based on FTIR

Spectral emissivity is an important parameter that dictates the extent of heat radiated from material surface. According to the definition of spectral emissivity, the experimental research on the spectral emissivity measurement was carried out based on the Fourier transform infrared(FTIR) spectrometer. The methods of spectrometer calibration were analyzed. The normal spectral emissivity of Cu was measured at different temperature. The results show that the linear fitting method can obtain the response function and background radiation of the FTIR spectrometer. The two-temperature method can calibrate the FTIR spectrometer quickly, the calibration accuracy is higher for the bigger temperature interval. The normal emissivity of Cu increases with increasing temperature, and decreases with increasing wavelength.