材料期刊网

作为高压电机主绝缘的重要组成部分,环氧桐马酸酐黏合剂的性能与电机安全稳定运行密切相关.为改善环氧桐马酸酐黏合剂的力学特性和耐老化特性,制备了质量分数分别为1 wt%、2 wt%、3 wt%和4 wt%的纳米SiO2/环氧桐马酸酐黏合剂,测试了其弯曲强度和冲击强度以及老化前后的击穿场强.结果表明:1 wt%纳米SiO2含量的纳米SiO2/环氧桐马酸酐黏合剂的弯曲强度提高24.79%,含2 wt%纳米SiO2的黏合剂冲击强度提高47.11%.老化前,纳米SiO2/环氧桐马酸酐黏合剂的击穿场强随纳米SiO2含量的增加先增加后减小,2 wt%含量时达到最大值,提高7.3%.电老化后和热老化初期,含1 wt%和2 wt%纳米SiO2的黏合剂击穿场强高于原始黏合剂,28天热老化后,各含量黏合剂的击穿场强与原始黏合剂趋于一致.

Epoxy tung-maleic anhydride adhesive is an important part of high voltage electrical machine main insulation, and affects the stable and safe operation of electrical machine directly.In order to improve the mechanical and aging property of the epoxy tung-maleic anhydride adhesive, the nano-SiO2/epoxy tung-maleic anhydride adhesive composites with the mass fraction of 1 wt%, 2 wt%, 3 wt% and 4 wt% nano-SiO2 were made respectively.The flexural strength and impact strength, and the breakdown strength before and after thermal aging and electrical aging of the composite were measured.The results indicate that flexural strength of 1 wt% nano-SiO2/epoxy tung-maleic anhydride adhesive composite increases by 24.79%, and impact strength of 2 wt% nano-SiO2 loading composite increases by 47.11%.Before the aging, the breakdown strength of the composites increases with the increasing of nano-SiO2 loading first, and then decrease.When the nano-SiO2 loading is 2 wt%, the breakdown strength of nano-SiO2/epoxy tung-maleic anhydride adhesive reaches the maximum and increases by 7.3%.After electrical aging as well as at early period of the thermal aging, the breakdown strength of 1 wt% and 2 wt% nano-SiO2 loading composite are higher than that of the unfilled adhesive.But at the end of 28 days thermal aging, the breakdown strength of all the composites and unfilled epoxy tung-maleic anhydride adhesive tend to be same.