Crystalline Destruction Mechanism Caused by Water Tree Based on Lamella Slip
Tao Xiantao, Li Hua, Fang Tian, Tang Letian, Lin Fuchang
State Key Laboratory of Advanced Electromagnetic Engineering and Technology Key Laboratory of Pulsed Power Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan 430074 China
Abstract：In this paper, the crystalline destruction of low density polyethylene (LDPE) caused by water tree was discussed, and a destruction mechanism based on lamella slips was proposed. After 500 hours of accelerated water tree aging on LDPE samples by the water-needle method, the cultivated water trees were observed by scanning electron microscope (SEM). The captured parallel distributed micro-channels are similar to the defects formed by mechanical-stress-caused lamella slip during tensile deformation. Through theoretical analysis, the electro-mechanical stress at the tips of the water tree micro-channels is able to cause the lamella slip. The crystalline parameters of the samples with/without water tree were analyzed by Raman spectroscopy (RS) and differential scanning calorimetry (DSC). The results reveal that the growth of water trees leads to the decrease of crystallinity and the increase of interfacial content, and the amorphous content remains unchanged. Therefore, this paper believes that the crystalline destruction mechanism was proposed based on the lamella slip caused by electro-mechanical stress is the main mechanism of the crystalline destruction.
陶霰韬, 李化, 方田, 唐乐天, 林福昌. 基于片晶滑移的水树结晶破坏机理[J]. 电工技术学报, 2021, 36(12): 2640-2649.
Tao Xiantao, Li Hua, Fang Tian, Tang Letian, Lin Fuchang. Crystalline Destruction Mechanism Caused by Water Tree Based on Lamella Slip. Transactions of China Electrotechnical Society, 2021, 36(12): 2640-2649.
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2021, Vol. 36 
