Using an Optical Pyrometer for Temperature Measurements of Shock-Compressed Polytetrafluoroethylene

摘要

Optical pyrometry is used to determine the shock-compression temperature of up to 51 GPa of polytetrafluoroethylene - a highly light scattering polymer in the uncompressed state. Conditions are considered under which the relative spectral characteristics of the radiating layer of shock-compressed polytetrafluoroethylene are close to the spectral characteristics of the scattered radiation detected from the end of the sample. A pyrometer for measuring the ratio of spectral radiances at four wavelengths from the range of 380-630 nm is described. The measured relative spectral radiances were approximated by the Planck curve normalized to unity at a wavelength of 630 nm. The approximation suggests that the detected radiation is of thermal nature. The average temperature from four experiments is 3100 ± 200 K. The measured temperature is compared with the results of previous calculations.