Dielectric properties of human phantom material using XLPE composite with shape memory characteristics

Dielectric properties and shape memory characteristics of carbon black/dielectrics/crosslinked polyethylene (XLPE) composite for human phantom materials were investigated. The complex dielectric constants of only carbon black filled XLPE composite were increased with the content of carbon black and showed the frequency dependence decreased with increasing frequency. The carbon black/dielectrics/XLPE composite showed the complex dielectric constant increasing with the amount of dielectrics at the constant concentration of carbon black. The decrease of dielectric constant with the frequency was also occurred by the effect of carbon black. The dielectric constant and conductivity required for the phantom material such as skull and brain at 600 MHz∼2 GHz could be obtained by adjusting the composition ratio of dielectric powder and carbon black. The XLPE composites simulating the skull and brain showed the good shape recoverability even though the relative increase of the residual strain was found in the thermomechanical cycling test by the addition of fillers. The solution to minimize the effect of air gap between a specific absorption rate measurement-access probe and a probe hole on the phantom model would be proposed in this study.