With a high voltage grade and large transmission capacity, ultra-high voltage (UHV) gas insulated metal enclosed transmission line (GIL) needs insulator with higher resistance to the comprehensive effect from electric, heat, and force. In this paper, epoxy composite materials were prepared by doping micro-Al2O3, micro-SiO2, and micro-Al2O3-SiO2 blend fillers, respectively. The mechanical, thermal, and electrical properties of the blend system were tested and analyzed. The results show that with the increase of the volume proportion of Al2O3, the comprehensive mechanical properties of the composites are improved, and pure micro-Al2O3/epoxy composite exhibits the best mechanical properties. Doping two fillers improves the thermal conductivity and arc resistance of the composites, but slightly reduces the glass transition temperature and increases the thermal expansion coefficient. When the volume ratio of Al2O3 and SiO2 in composites is 1:1, the arc resistance duration and the thermal conductivity of the composite reaches 1.198 W/(m·K) and 186.63 s, respectively. With the increase of the volume proportion of SiO2, the dielectric constant of the composites decreases, while the breakdown strength increases. The power frequency breakdown strength of the pure micro-SiO2/epoxy composites is the highest, reaching 36.63 kV/mm.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |