This paper mainly studies the effects of the composites which is low-density polyethylene (LDPE) modified by BiFeO3 powder on space charge characteristics under external magnetic field treatment. In comparison, the nano-BiFeO3 powder is irregular and small when the micron-BiFeO3 powder has regular shape and overlapping structure. XRD shows that BiFeO3 powders used in materials have pure phase. According to the DSC and magnetic properties, the saturation magnetization and crystallinity of the composites under the magnetic field treatment are significantly higher than that of pure LDPE. According to the space charge test, the space charge content in the composite is lower than that in the pure LDPE, when the space charge content of nano-composites is less than that in the micron-composites, and the space charge content is lower at 1 wt% concentration. Under the magnetic field treatment, the space charge distribution of the composites can be promoted; meanwhile, the electric field distribution of the composites can be more balanced. Overall, nano-composites has the best inhibition effect on space charge accumulation, followed by class B micron-composites. The inhibition effect of class A micron-composites is worst; electric field distribution is uneven at the same time.
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