温度和机械应力对GF/EP介电强度的影响

摘要

为了研究温度和机械应力对玻璃纤维/环氧树脂(Glass Fiber/Epoxy, GF/EP)复合材料介电强度的影响,分别在不同温度、不同应力大小和不同应力作用形式下对GF/EP复合材料进行了工频击穿试验,并依据电介质的击穿理论分析了温度和机械应力对其介电强度的影响规律.试验结果表明:在环境温度一定的情况下,GF/EP复合材料的击穿强度随拉应力的增大而减小;在弯曲正应力增大的初始阶段击穿强度有所上升,而后呈下降趋势;在确定的机械应力下,GF/EP复合材料低温和高温的介电强度都比室温下有所提高.研究结果为GF/EP复合材料在工程实际应用中提供了重要的实验基础.%To research the effects of temperature and mechanical stresses on the dielectric breakdown strength (DBS) of Glass Fiber/Epoxy (GF/EP) composites, the AC breakdown test has been carried out on the GF/EP composites under different temperatures、different stress magnitude and different style of the stresses, the effects of temperature and mechanical stresses on the dielectric strength have been analyzed according to the dielectric breakdown theory. The results show that: the dielectric strength of GF/EP composites decrease with increasing tensile stress under certain temperature; the dielectric strength increase at first with increasing bending stress, reach a maximum and indicate a decreasing tendency thereafter; compared to room temperature, the dielectric strength of GF/EP composites have been increased in different level under certain stress. The results provide important experimental basis for GF/EP composites in the practical application.