This letter details the metallization process of 3-D-printed WR-28 and WR-10 waveguides using electroplating. The 3-D printing technique is stereolithography, so the printed parts are plastic-based. A two-step metallization process is followed: a premetallization with nickel spray to make the part conductive and a subsequent electroplating process, emphasizing the chemical compounds and quantities needed to improve the result obtained, as well as the metallization times and currents applied on the parts. In addition, manufacturing deviations are measured and compensated. The results obtained are compared with simulations and commercial waveguide sections. Measurements show S11S_{11} below −33 and −21 dB for WR-28 and WR-10, respectively. Measured average losses are around 1 dB/m for WR-28 and 4 dB/m for WR-10, which is equivalent to copper with an effective surface roughness lower than 0.4 μm0.4~\mu \text{m} .

中文翻译：

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适用于毫米波设备的精确内部电镀和 3D 打印工艺指南


这封信详细介绍了使用电镀 3D 打印 WR-28 和 WR-10 波导的金属化工艺。 3D 打印技术是立体光刻技术，因此打印的部件是基于塑料的。接下来是两步金属化过程：用镍喷雾进行预金属化以使零件导电，然后进行电镀过程，强调改善所获得结果所需的化合物和数量，以及零件上施加的金属化时间和电流。此外，还测量并补偿制造偏差。将获得的结果与模拟和商业波导截面进行比较。测量结果显示，WR-28 和 WR-10 的 S11S_{11} 分别低于 -33 和 -21 dB。测得的平均损耗，WR-28 约为 1 dB/m，WR-10 约为 4 dB/m，相当于有效表面粗糙度低于 0.4 μm0.4~\mu \text{m} 的铜。