Electrode tips-fabrication technology for field emission electric propulsion thruster

For emitting tips of field emission electric propulsion(FEEP) thruster, some factors such as the concentration of the solution, the immersion depth and the etched voltage that influence the electrochemical etching of tungsten tips were investigated through the analysis of tips forming mechanism and the experiments. The optimum parameters for tip fabrication were determined. Emitting tip is fabricated in a 5 mol/L KOH solution at the immersion depth of 2 mm with the voltage of 6 V. After roughness treatment with AC current, the emitting tips for FEEP thruster were produced.