室温硫化硅橡胶绝缘保护材料冷热循环老化特性研究  

Study on Thermal-cooling Aging Characteristics of Room Temperature Vulcanized Silicone Rubber Insulation and Protection Materials

作　　者：金海云[1] 马佳炜 曾飏 丁昌昊 张晨曦 高乃奎[1] 张剑刚 JIN Haiyun;MA Jiawei;ZENG Yang;DING Changhao;ZHANG Chenxi;GAO Naikui;ZHANG Jiangang(State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学电力设备电气绝缘国家重点实验室,西安710049

出　　处：《高压电器》2020年第9期159-165,共7页High Voltage Apparatus

基　　金：国家自然科学基金资助项目(51272208)。

摘　　要：为探究工作在气温条件多变、昼夜温差大的环境下室温硫化硅橡胶(RTV)绝缘保护材料的老化特性,文中制备了RTV硅橡胶试样,并对其进行了冷热循环老化模拟试验,通过红外光谱测试(FTIR)及扫描电子显微镜(SEM)研究了老化前后微观结构的变化规律及老化机理,并通过拉伸试验、介电性能测试及击穿试验,分析了冷热循环老化过程中力学性能、体积电阻率、介电性能及击穿强度等宏观特性的变化规律。结果表明,冷热循环老化过程中,试样分子链交联网络劣化,同时产生-OH等强极性基团。在老化温度及高低交变温度应力共同作用下,试样近表面出现填料脱落、形成孔洞及裂纹的现象,微观结构受到一定程度的破坏,导致力学性能下降、体积电阻率减小、相对介电常数与介质损耗增大、击穿强度下降,整体绝缘性能劣化。In order to explore the aging characteristics of room temperature vulcanized silicone rubber(RTV) insulation protective material in the environment with conditions of variable temperature and large temperature difference between day and night,RTV samples were prepared and the thermal-cooling cycle aging simulation tests were conducted in this paper.The change laws of microstructure characteristics before and after aging and aging mechanism were studied through Fourier infrared spectroscopy(FTIR) and scanning electron microscopy(SEM).The tensile test,dielectric properties test and breakdown test were conducted to analyze the change laws of macro characteristi-s,such as mechanical properties,volume resistivity,dielectric properties,and breakdown strength during the thermal-cooling cycle aging process.The results showed that the molecular chain cross-linking network of samples deteriorated during the thermal-cooling cycle aging process,and strong polar groups(such as-OH) were generated at the same time.Under the combined effect of aging temperature and temperature stress,the phenomenon of filler shedding,formation of holes and cracks appeared on the near surface of the sample,and the microstructure was destroyed to a certain extent,resulting in decreased mechanical properties,reduced volume resistivity,increased relative permittivity and dielectric loss,and decreased breakdown strength.In general,overall insulation performance deteriorated.

关 键 词：室温硫化硅橡胶 绝缘保护 冷热循环老化 老化机理 力学特性 电学特性 

分 类 号：TM215.2[一般工业技术—材料科学与工程]