电子辐照对聚乙烯热缩套管力学性能的影响

利用45 keV,1 MeV和2 MeV电子分别对聚乙烯热缩套管进行辐照实验,研究不同能量电子辐照对聚乙烯热缩套管力学性能的影响,并分析电子辐照下材料的损伤效应机理,建立力学性能退化规律。结果表明：实验选定的3种能量电子辐照都会造成聚乙烯的降解,材料脆化产生裂纹,从而导致其力学性能下降；但是由于这3种能量电子穿透深度不同,45 keV电子只能造成聚乙烯热缩套管表层材料损伤,力学性能最大下降量只有30%~40%,而1 MeV和2 MeV电子却会导致套管力学性能完全丧失,力学性能下降接近100%。

Damage Effects of Electron Irradiation with Different Energy on Mechanical Properties of Polyethylene Heat-shrinkable Sleeves

Damage effects of electron irradiation with different energy on mechanical properties of polyethylene heat-shrinkable sleeves were studied by irradiating the sleeves with 45 keV, 1 MeV and 2 MeV electrons respectively. The mechanical property degradations of the sleeves before and after radiations were present. X-ray photoelectron spectra ( XPS) , scanning electronic microscopy ( SEM) and Fourier transform infrared spectroscopy ( FTIR) were used to analyze the element contents, the morphologies and the molecular struc-tures of the samples to study the damage mechanism of the sleeves. A degradation model for the changes of the mechanical properties of the sleeves in electron radiation environment was proposed. It is shown that the increase of irradiation degradation of the polyethylene causes the sleeves’ mechanical properties. For the penetration depth of different energy electrons in polyethylene is different, only a shallow layer the sleeves is affected by 45 keV energy electrons, while 1 MeV and 2 MeV energy electrons are penetrated the sleeves and cause the sleeves great damage. The mechanical properties of the sleeves are decreased by about 30% to 40% after 45 keV energy electron irradiation, and decreased by about 100% after 1 MeV and 2 MeV energy electron irradiation.