物理学报Issue(20)：1-8,8.DOI:10.7498/aps.63.209401
高能电子辐射下聚四氟乙烯深层充电特性
Research of deep dielectric charging characteristics of p olytetrafluoro ethene irradiated by energetic electrons
摘要
Abstract
Deep-layer dielectric charge and discharge in insulating material irradiated by energetic electrons are one of the major factors causing spacecraft anomalies. In this paper we establish a two-dimensional physical model of deep-layer dielectric charging, based on charge distribution and energy deposition of incident electrons and conductivity properties. The model is accomplished by finite element method, and the deep-layer dielectric charging characteristics of polytetrafluoroethene irradiated by energetic electrons are calculated. The calculation results show that in the vacuum environment, in the surface of the dielectric there exists a weak reverse electric field, and it first decreases to zero and then increases with the increase of depth. The maximum electric field appears near the ground, but the electric field presents a slight reduction at the position of ground point. Space-time evolution characteristics of the maximum potential and maximum electric field in different radiation times (one hour, one day, ten days and 30 days) within dielectric are analyzed. With the increase of radiation time, the maximum potential increases from-128 V to-7.9 × 104 V, and the maximum electric field increases from 2.83×105 V·m-1 to 1.76×108 V·m-1. Finally, the influence of electron-beam density on the maximum electric field is discussed. In a typical space environment (1 × 10-10 A·m-2), the maximum electric field reaches 2.95 × 106 V/m·m-1 for ten days. However, in severe space environment (2×10-8 A·m-2, the maximum electric field rapidly reaches 108 V/m for 42 hours, exceeding the breakdown threshold (about 108 V·m-1), which may easily cause electrostatic discharge). The physical model and numerical method can be used as a research basis of multi-dimension electric filed simulation of spacecraft complex parts.关键词
介质深层充电/聚四氟乙烯/高能电子辐射/二维电场仿真Key words
deep dielectric charging/polytetrafluoroethene/energetic electrons radiation/two dimension electric field simulation引用本文复制引用
李国,闵道敏,李盛涛,郑晓泉,茹佳胜..高能电子辐射下聚四氟乙烯深层充电特性[J].物理学报,2014,(20):1-8,8.基金项目
国家自然科学基金重点项目(批准号:51337008)和国家自然科学基金(批准号:11275146)资助的课题.* Project supported by the Key Program of the National Natural Science Foundation of China (Grant No.51337008) and the National Natural Science Foundation of China (Grant No.11275146) （批准号:51337008）
