热氧老化对10kV环网柜环氧基电缆套管材料性能影响

Infl uence of Thermal Oxidative Aging on the Properties of 10kV Ring Main Unit Epoxy-based Insulator

采用高温加速老化的方法,在200℃下对环氧基电缆套管样品进行了不同时间的热老化,并使用扫描电镜(SEM)、傅里叶红外光谱仪(FTIR)、万能试验机、热失重仪(TGA)以及体积电阻率测试仪等对样品性能进行了探究。SEM和FTIR的测试结果表明,随着老化时间的增加,电缆套管样品表面发生了降解并产生了大量的孔洞和颗粒,主要是样品基材主链断裂并产生有色基团。机械性能和电性能测试结果表明,样品的弯曲强度和体积电阻率随着老化时间增加呈先增大后减小的趋势。TGA结果表明,短期热老化会使样品产生后固化效应提升热稳定性,而长期老化则会产生降解使热稳定性降低。随后通过活化能测试及相应计算对样品的使用寿命进行了可靠性评估,发现在100℃使用工况条件下,该产品的理论服役寿命为19年。

The high-temperature accelerated aging method is used to thermally aging the insulator samples for epoxy-based cable warehouse casing at 200℃for different times,and use scanning electron microscope(SEM),Fourier infrared spectrometer(FTIR),and universal testing machine,thermogravimetry analysis(TGA)and electrical tester to explore the sample performance.The test results of SEM and FTIR show that as the aging time increases,the surface of the insulator sample is degraded and a large number of holes and particles are generated.Aging process breaks the main chain of the sample substrate and produces colored groups.The mechanical properties and electrical properties test results show that the bending strength and volume resistivity of the samples first increase and then decrease with the increase of aging time.TGA results show that short-term thermal aging will increase the thermal stability of the sample after curing,while long-term aging will cause degradation and reduce thermal stability.Subsequently,the service life of the sample is evaluated by the activation energy test and corresponding calculation,and the service life of the sample at 100℃is 19 years.