Delrin® for Propulsion with CO2 Laser: Carbon Doping Effects

Polyoxymethylene (POM) a.k.a. Delrin has been commonly used for propulsion with carbon dioxide (CO2) lasers as a solid fuel providing excellent combination of coupling coefficient and specific impulse. In this paper the propulsive characteristics of white and black (carbon‐doped) Delrin will be examined and compared. A Transverse Electric discharge in gas at Atmospheric pressure (TEA) CO2 laser with 300 ns pulse width was operated at up to 20 J pulse energy to produce irradiances on the order of 1–500 MW/cm2 on Delrin targets. Fourier Transform Infrared (FTIR) spectroscopy, time‐resolved force sensors, a ballistic pendulum, and Schlieren imaging techniques were used to determine absorption spectra, coupling coefficient, specific impulse, and internal efficiency of Delrin. An analysis will be made of the possible routes for force generation.