Anisotropy on electrical insulation performance of 3D printed nylon 12

3D printing (3DP) is developing rapidly and has been highly technology maturation, which has broad application prospects in making complex insulation structures which require special pre-designed electric field in uniform or uneven distribution. But the properties of the 3DP material are dependent with the anisotropic intrinsic, which is caused by the lamination manufacturing process. In this paper, the influences of traditional injection molding process (TIMP) and 3DP technology on physical and electrical properties are investigated by using 1mm Nylon12. In the 3DP process, the thickness of the individual laminated layer is 0.1mm. And in order to study the anisotropy of 3DP process, the printing direction is set to be in perpendicular (90°) and parallel (0°) to the electric field direction (thickness direction). The physical and electrical insulation performance, such as density, dc and ac breakdown strength and volume resistivity are studied by using Nylon 12 made by TIMP and 3DP of 0°and 90°. Experimental results indicate that the breakdown electric field and volume resistivity of TIMP is much higher than 3DP materials; under high frequency, the permittivity of 3DP and TIMP is similar, however, under low frequency, the permittivity of 3DP materials is higher than TIMP. Under different printing angles, the volume resistivity and breakdown electric field in the direction of 90° is higher than that in the direction of 0°. The reason for the difference between 3DP and TIMP samples is that there is a gap between layers which results in the decrease of performance. Meanwhile, the equivalent parameters of different direction samples change, resulting in anisotropy of electrical properties.