Additively manufactured WR-10 copper waveguide

Abstract

Direct additive manufacturing method utilizing electron beam melting techniques was employed to produce fully dense oxygen free copper W-band waveguides. By employing smaller copper powder, finer deposition layer, and spot-melting methodology surface roughness average has been reduced from 44 μm to 28 μm. A magnetically driven abrasive process was then employed to demonstrate further surface roughness average improvement of 5 μm. Initial RF test results on as-printed WR-10 waveguide confirm that surface post-processing will be essential to implementation of additive manufacturing techniques in vacuum electronics.