Manufacture of insulating agents for electric field relaxation using functionally graded materials, with electric field calculations

The authors of this paper have previously developed a successive layer accretion method based on vacuum filtration, for the manufacture of functionally graded materials (FGMs) by a progressive lamination procedure. For this, they have been granted a U.S. Patent. Using this method, it is possible to manufacture FGMs with thicknesses ranging from several millimetres to several centimetres. The authors have previously manufactured functionally graded materials consisting of iron (III) oxide-kaolin, copper oxide-kaolin and titanium oxide-kaolin, using the said successive layer accretion method. The manufactured FGMs were examined using an SEM to investigate their grading characteristics. Electrical properties such as resistivity, permittivity and permeability were also measured. In the present paper, they report results of permittivity and resistivity measurements conducted on an FGM consisting of titanium oxide and kaolin