Table 2.

Coefficient of energy efficiency, for studied systems, at three different charging voltages.

Filler Content in Specimens (phr)	neff (%)
	50 V	100 V	150 V
Neat epoxy	23.31	26.59	30.76
5 Fe3O4/10 BaTiO3	35.40	38.74	60.56
10 Fe3O4/10 BaTiO3	41.54	49.82	62.23
15 Fe3O4/10 BaTiO3	45.10	56.99	79.23
20 Fe3O4/10 BaTiO3	48.24	53.19	64.73
40 Fe3O4/10 BaTiO3	52.54	61.35	17.47
50 Fe3O4/10 BaTiO3	55.72	64.42	-