Application of 3-D Metal Printing to Microwave Components and Antennas

3-D printing has been developed very rapidly in microwave device applications over the past few years. Metal printing is an additive manufacturing technique of synthesizing metallic parts from metal alloy power, which is totally different from the traditional machining method or "subtractive manufacturing". The latter usually introduces some errors in terms of accuracy, alignment and assembly, inevitably degrading the performance of the devices, especially the efficiency at high frequency. This paper looks at the application of Direct Metal Laser Sintering (DMLS) to microwave components and antennas. The advent and the maturing of the DMLS technology may revive the fortunes of these devices as designs that are previously difficult to fabricate can be now easily handled. Some newly developed examples implemented via DMLS technique are also included in this paper.