Ablation Performance Experiments With Metal Seeded Polymers

The specific impulse of plain polymers has been found too low for application in pulsed laser propulsion for single stage to orbit flights. Therefore, ablation tests with polymers, seeded with Al and Mg powder in various concentrations to reduce the absorption depth, have been conducted with CO2 pulses up to 280 J and ~12 is pulse length to measure the coupling coefficient and specific impulse in air and in vacuum. A large and increasing loss of pulse energy, presumably deposited in a decoupled absorption wave, has been found for increasing laser pulse energy. This loss prevents the achievement of better results compared to unseeded material.