Abstract：It is found that surface charge accumulated on polymer insulating materials used in radioactive environment leads to serious discharge accident. Thus, from the safety point of view, it is necessary to investigate whether the surface charge behavior of polymer is altered by irradiation. In this paper, polyethylene (PE) is employed as test sample which is previously irradiated in air up to 100 kGy and then up to 1000 kGy with dosage rate of 10 kGy/h by using a 60Co gamma-source. The charges are injected onto sample surface by employing needle-plane electrode arrangement, where the needle electrode is connected to a dc high voltage source and the plane electrode is grounded. An electrostatic probe is designed to measure surface charge density immediately after the surface is charged. The results show that the amount of negative charge is larger than that of positive charge regardless of the total dose of gamma-ray irradiation. With increasing the total dose of gamma-ray irradiation, the total charge on PE surface initially decreases then increases. It is suggested that the capacity of PE surface for storing charges depends upon the density of localized surface states, which is changed by radiation induced cross-linking and degradation reactions of molecule structure of PE.
杜伯学, 高宇, 马宗乐. 伽玛线辐射对聚乙烯表面电荷累积的影响[J]. 电工技术学报, 2009, 24(6): 1-4.
Du Boxue, Gao Yu, Ma Zongle. Effects of Gamma-Ray Irradiation on Surface Charge Accumulation of Polyethylene. Transactions of China Electrotechnical Society, 2009, 24(6): 1-4.
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