Relative permittivity and electric strength at AC and surge voltage of dielectrics printed by focused deposition modelling

A study of the relative permittivity and electric strength of dielectrics printed by focus deposition modeling was presented. These electrical parameters determined the life-time reliability of devices made of dielectrics. Samples of PLA, ABS, PETG and ASA were tested according to IEC specifications. The dependence of the electrical properties of the samples on the type of material and printing precision was observed. Relative permittivity tests were carried out in the acoustic frequency band from 20 Hz to 20 kHz. It allowed analysis in a higher band than has been done in other publications to date. The electric strength of materials at 1.2/50 μs surge voltage was examined, which has not been widely analyzed before. Weibull plots, as a basis for determining the risk of failure, were prepared. The PETG FR (flame retardant) had the highest electric strength value, while PLA had the lowest. The differences with respect to tests at AC voltage were demonstrated. The printing technique affects the electrical strength value and location of potential electrical break-down.