Abstract Heaterless hollow cathodes are increasingly attractive for low-power electric propulsion systems due to their compact size and lack of a heater and associated power supply which are well-known failure mechanisms. A low-current, ultra-compact, heaterless, lanthanum hexaboride (LaB6) hollow cathode has been developed for the Magnetically Shielded Miniature (MaSMi) Hall thruster, which is part of the Jet Propulsion Laboratory's Ascendant Sub-kW Transcelestial Electric Propulsion System (ASTRAEUS) aimed at enabling interplanetary missions with high-Δv SmallSats. In the framework of that program, there is an increasing focus on the reliability and life cababilities of every system component. MaSMi's low-current center-mounted heaterless hollow cathode, specifically designed to reduce thermal losses and maximize life, is required to demonstrate a minimum of 5700 h of continuous operation at its peak discharge current of 4 A with a minimum of 1200 ignitions. One of the most critical aspects of the cathode operation is understanding the life implications of repeated heaterless ignitions and any impacts on cathode performance. To understand this issue, an ignition cycling test was performed at JPL. The test successfully demonstrated more than 25,000 heaterless ignitions of the cathode. Measurements of cathode parameters such as discharge and keeper voltage showed that the cathode steady-state operation was not degraded by the repeated ignitions. Photos after cycle testing of the cathode orifice plate, keeper orifice plate, and a cross section of the entire cathode assembly, show surface roughening and some graphite deposition on cathode electrodes from microarcing during the ignitions, but no significant damage inhibiting continued cathode operation.

中文翻译：

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在原型飞行紧凑型无加热器六硼化镧空心阴极上演示 25,000 次点火

摘要 无加热器空心阴极由于其紧凑的尺寸和缺乏众所周知的故障机制的加热器和相关电源，因此对低功率电力推进系统越来越有吸引力。已为磁屏蔽微型 (MaSMi) 霍尔推进器开发了一种低电流、超紧凑、无加热器的六硼化镧 (LaB6) 空心阴极，该推进器是喷气推进实验室 Ascendant Sub-kW 超天体电力推进系统 (ASTRAEUS) 的一部分) 旨在通过高 Δv SmallSats 实现行星际任务。在该计划的框架内，人们越来越关注每个系统组件的可靠性和寿命能力。MaSMi 的低电流中心安装无加热器空心阴极，专为减少热损失和最大限度地延长使用寿命而设计，要求证明在其峰值放电电流为 4 A 的情况下连续运行至少 5700 小时，至少点火 1200 次。阴极操作最关键的方面之一是了解重复无加热器点火对寿命的影响以及对阴极性能的任何影响。为了理解这个问题，在喷气推进实验室进行了点火循环测试。该测试成功地证明了阴极的 25,000 多次无加热器点火。阴极参数（如放电和保持电压）的测量表明阴极稳态操作不会因重复点火而降低。阴极孔板、保持孔板和整个阴极组件的横截面循环测试后的照片，