Electromagnetic performance of Ti6Al4V and AlSi7Mg0.6 waveguides with laser beam melting (LBM) produced and abrasive flow machining (AFM) finished internal surfaces

Abstract

Metal additive manufacturing processes, such as laser beam melting (LBM), can play a key role in developing antenna-feed chains because monolithic and multifunctional parts can be manufactured with high geometric freedom in the design phase. Using LBM technology, lighter and more compact antennas can be produced and manufacturing costs can be reduced. However, the surface roughness of internal surfaces in waveguides produced by LBM is much higher (about 10 μm Ra) than that produced by conventional manufacturing technologies. Consequently, such high surface roughness of the internal surface can affect electrical current propagation through the waveguide and corresponding transmitted power. In this paper, abrasive flow machining (AFM) was used to reduce the surface roughness of the internal surfaces of four different waveguides used at both K and Q bands. A significant reduction in the transmission loss at both K and Q bands was observed as their internal surface roughness decreased from about 10 μm to 1 μm Ra. This was assumed to be due to an increase of the internal surface electrical conductivity with the decrease of roughness in waveguides channels.

KEYWORDS:

• Electromagnetic performance
• waveguide
• additive manufacturing
• laser beam melting (LBM)
• abrasive flow machining (AFM)
• internal surface
• surface roughness

Acknowledgements

The ‘La région Auvergne Rhône-Alpes' in France is acknowledged for funding the purchase of the AFM machine (Extrude Hone^®). A special thank goes to Extrude Hone for providing the AFM medium. The authors are grateful to M. Cici, H. Seux, and P. Polly for making and modifying the fixture parts.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by I@L Carnot MELTED.

Notes on contributors

Mathieu François

Mathieu François received his MSc in Mechanics, Materials and Processes from Arts et Métiers ParisTech School of Engineering in 2016. He received his PhD from Arts et Métiers ParisTech, Paris, France, in 2020. He worked as a PhD candidate at Thales SIX GTS France with a partnership with Arts et Métiers ParisTech School of Engineering and the French National Center for Scientific Research.

Sangil Han

Sangil Han is a Postdoctoral Researcher of Laboratoire de Tribologie et Dynamique des Systèmes (LTDS) at the Université de Lyon, Ecole Centrale de Lyon – ENISE, France. He received his BS in agricultural machinery and process engineering from Seoul National University, South Korea, in 2000, and his PhD in mechanical engineering from the Georgia Institute of Technology, GA, USA, in 2006. He previously worked as a Senior Research Engineer at Samsung Electronics, South Korea. His research interest aims at experiment and modeling hard turning, abrasive flow machining (AFM) and sequence machining.

Frédéric Segonds

Frédéric Segonds is an Associate Professor of Mechanical Engineering at Arts et Métiers ParisTech, Paris, France and a member of the Product Design and Innovation Laboratory (LCPI). His research interest aims at ‘Creativity and Design With/For/By Additive Manufacturing'.

Corinne Dupuy

Corinne Dupuy is a Researcher of the Processes and Engineering in Mechanics and Materials Laboratory (PIMM), Paris, France.

Mickaël Rivette

Mickaël Rivette is an Associate Professor of Arts et Métiers ParisTech, Metz, France and a member of the Manufacturing Engineering and Control Laboratory (LCFC). His research interest focuses on design for additive manufacturing.

Simon Turpault

Simon Turpault is an Engineering Technologist of Thales SIX GTS France, Cholet, France. He is specialized in materials, processes, and additive manufacturing.

Mehdi Mimouna

Mehdi Mimouna is a Researcher of OPS-Hardware Techno. Tools & Engineering, Thales SIX GTS France, Gennevilliers, France

Ferdinando Salvatore

Ferdinando Salvatore is an Associate Professor of Laboratoire de Tribologie et Dynamique des Systèmes (LTDS) at the Université de Lyon, Ecole Centrale de Lyon – ENISE, France. His research focuses on finishing processes, such as abrasive flow machining (AFM), drag finishing, and electrochemical mechanical polishing.

Joël Rech

Joël Rech is a Professor of Laboratoire de Tribologie et Dynamique des Systèmes (LTDS) at the Université de Lyon, Ecole Centrale de Lyon – ENISE, France. He leads a research group of 23 people working on the characterization and modelling of physical phenomena at the tool/work material interface in cutting and superfinishing operations. He made remarkable breakthroughs in numerical modeling of surface integrity induced by cutting and polishing processes (residual stresses, roughness, microstructure) and in modeling of tribological phenomena (friction, wear etc.) of cutting tools.

Patrice Peyre

Patrice Peyre is a Research Director of Arts et Métiers ParisTech, Paris, France and a member of the Processes and Engineering in Mechanics and Materials Laboratory (PIMM) and the French National Center for Scientific Research. His research focuses on material science, laser processes and additive manufacturing.