Could nanodielectrics operate stably under coupling multi-physics for a long time? In recent years

nanodielectrics have been demonstrated in improving short-term electrical performance of electrical devices

but their long-term operational performance is still inadequate. In this work

silicone rubber material used for DC cable accessories is selected

and nano Al2O3 and TiO2 are selected as fillers. The physicochemical properties

mechanical properties and electrical properties under coupling thermal-mechanical aging are characterized and discussed. It is found that as aging time increases

secondary crosslinking occurs inside the material

followed by degradation and the formation of microcracks. As aging time progresses

the electric characteristics of various groups exhibit an initial rise followed by a gradual decrease. The aging resistance of nano-doped silicone rubber is maintained under the low mechanical stress-thermal coupling aging. However

under high stress-thermal coupling aging

the performance drops significantly

even worse than undoped materials. The relevant research provides a theoretical basis for the long-term stability evaluation and material design research of cable accessory insulation materials.