3D Printed Cryogenic High Voltage Devices

Progress in three-dimensional (3D) printing opens new ways to produce complex structures, and therefore, 3D printing may be an appropriate fabrication method for novel cryogenic high voltage devices with special geometrical requirements. A simple 3D printer “Ultimaker Original” with heated printbed is used for printing test samples. First, some tests were performed with one sample geometry type using the materials polyamide, polystyrene, polylactic acid, and acrylonitrile butadiene styrene (ABS). The results with the ABS material concerning mechanical, cryogenic, and leak tightness properties were considered as most promising. High voltage breakdown strength of ABS disk samples was examined based on standard IEC 60243 for alternating, direct, and standard lightning impulse voltage with liquid nitrogen as surrounding medium. In addition, flashover voltage tests were performed. Finally, the following prototype high voltage devices were printed and partly tested: high voltage insulator, minicryostat equipped with a standard 10 kV bushing, cryogenic axial insulation break, room temperature insulation break, and feedthrough. Some of the first results are promising, but further development is necessary. In particular, leak tightness needs improvement, and shock cooldown to liquid nitrogen temperature must be avoided because it causes ABS material destruction.