Phys.org July 8, 2024 GHz burst-mode femtosecond (fs) laser provides distinct characteristics in materials processing as compared with the conventional irradiation scheme of fs laser (single-pulse mode). Researchers in Japan used the moderate pulse interval of 205 ps in the burst pulse for high-quality and high-efficiency micromachining of single crystalline sapphire by laser induced plasma assisted ablation (LIPAA). The preceding pulses in the burst generated plasma by ablation of copper placed behind the sapphire substrate, which interacted with the subsequent pulses to induce ablation at the rear surface of sapphire substrates. The ablation quality, efficiency, and the fabrication resolution were […]
Tag Archives: Ablation
Performance of electric solid propellant
Science Daily September 3, 2019 Electric solid propellants are being explored for use in dual-mode rocket engines because they aren’t susceptible to ignite from a spark or flame and can be turned on and off electrically. A team of researchers in the US (Missouri University of Science and Technology, University of Illinois, NASA Marshall Space Flight Center) compares a high-performance electric propellant with polytetrafluoroethylene (PTFE), a traditional propellant used in ablative pulsed plasma thrusters. They found that the electric solid propellant ablates about two times more than the traditional propellant. According to their analyses the physics of propellant ablation is […]