Page 89 - 《真空与低温》2025年第3期

真空与低温 第 31 卷 第 3 期
360 Vacuum and Cryogenics 2025 年 5 月

面 向 空 间 应 用 的 铱 -氧 化 钇 灯 丝 研 制

李志伟，李 洋，张光华，毛舒宇，郭等柱，魏贤龙 *
（北京大学电子学院 纳米器件物理与化学教育部重点实验室，北京 100871）

摘要：真空电子器件在空间应用中具有关键作用，其核心电子源需满足高发射电流、抗振动冲击、抗热冲击
及长寿命等严苛要求。现有热发射灯丝中，铱-氧化钇灯丝抗氧化性强，但发射性能有限。面向空间应用设计了螺
旋形铱-氧化钇灯丝，显著提升了发射性能，单个灯丝的发射电流超 200 mA。同时，为灯丝引入了绝缘支撑结构，
显著增强了抗振性能和连续工作能力。所制备的螺旋灯丝通过了鉴定级测试，并可以连续工作 2 300 h 以上。研
究表明了铱-氧化钇灯丝的卓越性能，拓展了其在航天领域的应用前景。
关键词：热电子发射；热阴极；氧化钇；空间应用；商业航天
中图分类号：TB71 文献标志码：A 文章编号：1006−7086（2025）03−0360−05
DOI：10.12446/j.issn.1006-7086.2025.03.011

Study on Iridium-yttrium Oxide Filaments for Space Applications

*
LI Zhiwei，LI Yang，ZHANG Guanghua，MAO Shuyu，GUO Dengzhu，WEI Xianlong
（The Key Laboratory for the Physics and Chemistry of Nanodevices，School of Electronics，
Peking University，Beijing 100871，China）

Abstract：Electron and ion sources based on thermionic emission filaments are widely used in various space applications，
such as ionization sources for ion thrusters，neutralizers for different types of electric thrusters，ionization sources for leak de-
tectors and mass spectrometers，and ionization vacuum gauges. The electron sources in these devices face stringent require-
ments such as high emission current，resistance to vibration and thermal shock，and long lifespan. The existing thermionic
emission filaments primarily include tungsten filaments， thoriated tungsten filaments， and iridium-yttrium oxide filaments.
Among these， thoriated tungsten filaments exhibit excellent emission performance but are radioactive. Tungsten filaments
have low emission efficiency and poor oxidation resistance. Iridium-yttrium oxide filaments are non-radioactive and possess
good oxidation resistance，but their emission performance is relatively low. In helium mass spectrometers and ionization vac-
uum gauges，traditional iridium-yttrium oxide filaments mostly use a straight-wire structure，with emission currents typically
ranging from 0.1 to 10 mA. This study designs a spiral iridium-yttrium oxide filament for space applications，which signifi-
cantly improves the emission performance，with a single filament emission current exceeding 200 mA. At the same time，an
insulating support structure is introduced for the filament，which significantly enhances its vibration resistance and continu-
ous working ability. The filament partially contacts the support structure both during operation and non-operating periods，
achieving spatial positioning and stabilization through this “soft contact”. This prevents performance degradation caused by
solder joint detachment or high-temperature deformation， thereby improving the filament’s adaptability and stability under
the harsh conditions of space. The prepared spiral filament has passed the qualification test and can work continuously for
more than 2 300 hours. This study demonstrates the excellent performance of iridium-yttrium oxide filaments and expands its
application prospects in the aerospace field.
Key words：thermionic emission；hot cathode；yttrium oxide；space application；commercial spaceflight

收稿日期：2024−11−29
基金项目：国家自然科学基金（62350040）
作者简介：李志伟，博士，特聘副研究员。E-mail：lzw111@pku.edu.cn
通信作者：魏贤龙，博士，研究员。E-mail：weixl@pku.edu.cn