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| The Effect of Combined Thermal-Mechanical Aging on the Cross-Linking Network and Mechanical and Electrical Properties of Silicone Rubber |
| Zhou Yuanxiang1,2, Zhang Zhenghui1, Zhang Yunxiao2, Zhu Xiaoqiqan2, Huang Meng3 |
1. The Wind Solar Storage Division of State Key Lab of Control and Simulation of Power System and Generation Equipment School of Electrical Engineering Xinjiang University Urumqi 830047 China;
2. State Key Lab of Control and Simulation of Power System and Generation Equipment Department of Electrical Engineering Tsinghua University Beijing 100084 China;
3. State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing 102206 China |
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Abstract This study aims to explore the effect of the combined thermal-mechanical stress on the insulation performance of the silicone rubber in cable accessories. Specifically, a combined thermal-mechanical aging test of the silicone rubber was designed and conducted; the mechanical properties, electrical properties, and microstructure of silicone rubber before and after thermal aging were compared and analyzed. As aging increases, the tensile strength and elongation at break of the specimen decreases and the hardness increases, respectively. The breakdown strength of the sample first increases and then decreases after thermal aging. Under certain aging time, the breakdown strength decreases with the increasing tensile stress while the relative dielectric constant gradually increases. The test results of cross-linking density and infrared spectroscopy suggest that at the early aging stage, the oxidative cross-linking reaction occurs between the main chains of the silicone rubber, leading to the decreased free volume and carrier mobility and increased breakdown strength; at the later aging stage, the cross-linked system structure and the molecular chain is destroyed, causing the increased free volume and carrier mobility and decreased breakdown strength. Under the action of mechanical stress coupling, the curled molecular chain is stretched along the direction of mechanical stress, and the stretched molecular chain is more likely to break at high temperatures. As a result, the insulation performance of the material further deteriorates. These results lay a theoretical foundation for the assessment of the aging state of silicone rubber for cable accessories.
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Received: 20 July 2021
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[1] 杜伯学, 韩晨磊, 李进, 等. 高压直流电缆聚乙烯绝缘材料研究现状[J]. 电工技术学报, 2019, 34(1): 179-191.
Du Boxue, Han Chenlei, Li Jin, et al.Research status of polyethylene insulation for high voltage direct current cables[J]. Transactions of China Electro-technical Society, 2019, 34(1): 179-191.
[2] 黄兴溢, 张军, 江平开. 热塑性电力电缆绝缘材料: 历史与发展[J]. 高电压技术, 2018, 44(5): 1377-1398.
Huang Xingyi, Zhang Jun, Jiang Pingkai.Thermoplastic insulation materials for power cables: history and progress[J]. High Voltage Engineering, 2018, 44(5): 1377-1398.
[3] 单秉亮, 李舒宁, 杨霄, 等. XLPE配电电缆缺陷诊断与定位技术面临的关键问题[J]. 电工技术学报, 2021, 36(22): 4809-4819.
Shan Bingliang, Li Shuning, Yang Xiao, et al.Key problems faced by defect diagnosis and location technologies for XLPE distribution cables[J]. Transactions of China Electrotechnical Society, 2021, 36(22): 4809-4819.
[4] 周远翔, 张云霄, 陈铮铮, 等. 机械应力对硅橡胶电树枝起始性能的影响[J]. 绝缘材料, 2017, 50(2): 53-57, 63.
Zhou Yuanxiang, Zhang Yunxiao, Chen Zhengzheng, et al.Effects of mechanical stress on electrical tree initiation in silicone rubber[J]. Insulating Materials, 2017, 50(2): 53-57, 63.
[5] Pohmer K.High temperature addition curable silicone rubbers innovations and new developments[J]. Kautschuk und Gummi Kunststoffe, 2001, 54(7-8): 368-371.
[6] 陈杰, 吴世林, 胡丽斌, 等. 退役高压电缆附件绝缘状态及理化性能分析[J]. 电工技术学报, 2021, 36(12): 2650-2658.
Chen Jie, Wu Shilin, Hu Libin, et al.Analysis of insulation state and physicochemical property of retired high-voltage cable accessories[J]. Transactions of China Electrotechnical Society, 2021, 36(12): 2650-2658.
[7] 黄光磊, 李喆, 杨丰源, 等. 直流交联聚乙烯电缆泄漏电流试验特性研究[J]. 电工技术学报, 2019, 34(1): 192-201.
Huang Guanglei, Li Zhe, Yang Fengyuan, et al.Experimental research on leakage current of DC cross linked polyethylene cable[J]. Transactions of China Electrotechnical Society, 2019, 34(1): 192-201.
[8] 费益军, 张云霄, 周远翔. 硅橡胶热老化特性及其对电缆附件运行可靠性的影响[J]. 电工电能新技术, 2014, 33(12): 30-34.
Fei Yijun, Zhang Yunxiao, Zhou Yuanxiang.Thermo characteristics of Silicone rubber and its effects on operational reliability of extra-high voltage cable accessories[J]. Advanced Technology of Electrical Engineering and Energy, 2014, 33(12): 30-34.
[9] 王佩龙. 高压电缆附件的电场及界面压力设计[J]. 电线电缆, 2011(5): 1-4, 10.
Wang Peilong.Electrical field and interface pressure control in HV cable accessories design[J]. Electric Wire & Cable, 2011(5): 1-4, 10.
[10] 周远翔, 张云霄, 张旭, 等. 热老化时间对硅橡胶电树枝起始特性的影响[J]. 高电压技术, 2014, 40(4): 979-986.
Zhou Yuanxiang, Zhang Yunxiao, Zhang Xu, et al.Influence of thermal aging time on electrical tree initiation of silicone rubber[J]. High Voltage Engineering, 2014, 40(4): 979-986.
[11] 吕鸿, 马佳炜, 杨贤, 等. 热老化对220 kV硅橡胶电缆接头绝缘材料介电性能的影响[J]. 绝缘材料, 2019, 52(2): 47-51.
Lü Hong, Ma Jiawei, Yang Xian, et al.Influence of thermal ageing on dielectric properties of insulating materials in 220 kV silicone rubber cable joint[J]. Insulating Materials, 2019, 52(2): 47-51.
[12] 陈庆国, 尚南强, 魏昕喆. 热老化对液体硅橡胶材料介电性能及力学特性的影响研究[J]. 电机与控制学报, 2020, 24(4): 141-148.
Chen Qingguo, Shang Nanqiang, Wei Xinzhe.Influence of thermal oxygen aging on dielectric and mechanical properties of liquid silicone rubber[J]. Electric Machines and Control, 2020, 24(4): 141-148.
[13] Kashi S, Varley R, de Souza M, et al. Mechanical, thermal, and morphological behavior of silicone rubber during accelerated aging[J]. Polymer-Plastics Technology and Engineering, 2018, 57(16): 1687-1696.
[14] Ito S, Hirai N, Ohki Y.Changes in mechanical and dielectric properties of silicone rubber induced by severe aging[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2020, 27(3): 722-730.
[15] 杜伯学, 苏金刚, 徐航, 等. 机械应力下高温硫化硅橡胶电树枝生长特性[J]. 中国电机工程学报, 2016, 36(24): 6627-6634, 6915.
Du Boxue, Su Jingang, Xu Hang, et al.Treeing growth characteristics in HTV silicone rubber considering mechanical stress[J]. Proceedings of the CSEE, 2016, 36(24): 6627-6634, 6915.
[16] 惠宝军, 彭阳涛, 傅明利, 等. 机械应力作用下硅橡胶材料的击穿特性研究[J]. 绝缘材料, 2019, 52(7): 29-35.
Hui Baojun, Peng Yangtao, Fu Mingli, et al.Breakdown characteristics of silicone rubber under mechanical stress[J]. Insulating Materials, 2019, 52(7): 29-35.
[17] 刘昌, 惠宝军, 傅明利, 等. 机械应力对硅橡胶高压电缆附件运行可靠性的影响[J]. 高电压技术, 2018, 44(2): 518-526.
Liu Chang, Hui Baojun, Fu Mingli, et al.Influence of mechanical stress on the operation reliability of silicone rubber high voltage cable accessories[J]. High Voltage Engineering, 2018, 44(2): 518-526.
[18] Liu Ying, Wang Xing.Research on property variation of silicone rubber and EPDM rubber under interfacial multi-stresses[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2019, 26(6): 2027-2035.
[19] Wang Xia, Wang Chencheng, Wu Kai, et al.An improved optimal design scheme for high voltage cable accessories[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2014, 21(1): 5-15.
[20] 张志劲, 张翼, 蒋兴良, 等. 自然环境不同年限复合绝缘子硅橡胶材料老化特性表征方法研究[J]. 电工技术学报, 2020, 35(6): 1368-1376.
Zhang Zhijin, Zhang Yi, Jiang Xingliang, et al.Study on aging characterization methods of composite insulators aging in natural environment for different years[J]. Transactions of China Electrotechnical Society, 2020, 35(6): 1368-1376.
[21] 汪佛池, 律方成, 杨升杰, 等. 基于FTIR的110kV复合绝缘子硅橡胶伞裙老化性能分析[J]. 电工技术学报, 2015, 30(8): 297-303.
Wang Fochi, Lü Fangcheng, Yang Shengjie, et al.The aging characteristic of silicon rubber sheds of 110kV composite insulators based on FTIR test[J]. Transactions of China Electrotechnical Society, 2015, 30(8): 297-303.
[22] 夏云峰, 宋新明, 何建宗, 等. 复合绝缘子用硅橡胶老化状态评估方法[J]. 电工技术学报, 2019, 34(增刊1): 440-448.
Xia Yunfeng, Song Xinming, He Jianzong, et al.Evaluation method of aging for silicone rubber of composite insulator[J]. Transactions of China Electrotechnical Society, 2019, 34(S1): 440-448.
[23] 王若丞, 贺云逸, 康洪玮, 等. 电缆接头绝缘用硅橡胶热老化及超声特性[J]. 高电压技术, 2021, 47(9): 3181-3188.
Wang Ruocheng, He Yunyi, Kang Hongwei, et al.Thermal aging and ultrasonic characteristics of silicone rubber for cable joint insulation[J]. High Voltage Engineering, 2021, 47(9): 3181-3188.
[24] Hillborg H, Ankner J F, Gedde U W, et al.Crosslinked polydimethylsiloxane exposed to oxygen plasma studied by neutron reflectometry and other surface specific techniques[J]. Polymer, 2000, 41(18): 6851-6863.
[25] Ma Bin, Gubanski S M, Hillborg H.AC and DC zone-induced ageing of HTV silicone rubber[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2011, 18(6): 1984-1994.
[26] Flory P J, Rehner J.Statistical mechanics of cross-linked polymer networks I. rubberlike elasticity[J]. The Journal of Chemical Physics, 1943, 11(11): 512-520.
[27] 周远翔, 刘睿, 张云霄, 等. 硅橡胶电树枝的引发与生长过程[J]. 高电压技术, 2014, 40(12): 3656-3664.
Zhou Yuanxiang, Liu Rui, Zhang Yunxiao, et al.Initiation and propagation processes of electrical tree in silicone rubber[J]. High Voltage Engineering, 2014, 40(12): 3656-3664.
[28] 李昂. 橡胶的老化现象及其老化机理[J]. 特种橡胶制品, 2009, 30(5): 56-67.
[29] 付秋兰, 吴向荣, 温茂添. 缩合型室温硫化硅橡胶耐热性的研究进展[J]. 有机硅材料, 2003, 17(1): 28-31, 51.
Fu Qiulan, Wu Xiangrong, Wen Maotian.Study progress on thermal stability of condensed type RTV silicone rubber[J]. Silicone Material, 2003, 17(1): 28-31, 51.
[30] 张丽新, 杨世勤, 何士禹. 质子辐照空间级硅橡胶的正电子淹没寿命谱研究[J]. 强激光与粒子束, 2002, 14(4): 629-632.
Zhang Lixin, Yang Shiqin, He Shiyu.Study on positron annihilation lifetime spectrum of polysilicone rubber after proton radiation[J]. High Power Laser & Particle Beams, 2002, 14(4): 629-632.
[31] Artbauer J.Electric strength of polymers[J]. Journal of Physics D: Applied Physics, 1996, 29(2): 446-456.
[32] Park C H, Okajima K, Hara M, et al. Effect of heat treatment on dielectric strength of polyethylene terephthalate under compressive stress[J]. IEEE Transactions on Electrical Insulation, 1983, EI-18(4): 380-389.
[33] 杨洪, 申屠宝卿. 硅橡胶的耐热稳定性[J]. 合成橡胶工业, 2005, 28(3): 229-233.
Yang Hong, Shentu Baoqing.Heat stability resistance of silicone rubber[J]. Synthtrc Rubber Industry, 2005, 28(3): 229-233.
[34] 梁曦东, 周远翔, 曾嵘. 高电压工程[M]. 2版. 北京: 清华大学出版社, 2015.
[35] Roberts S.Dielectric constants and polarizabilities of ions in simple crystals and barium titanate[J]. Physical Review, 1949, 76(8): 1215-1220. |
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2022, Vol. 37 
