Azar Maalouf

Full 3-D Printed Microwave Termination: A Simple and Low-Cost Solution

This paper describes the realization and characterization of microwave 3-D printed loads in rectangular waveguide technology. Several commercial materials were characterized at X-band (8-12 GHz). Their dielectric properties were extracted through the use of a cavity-perturbation method and a transmission/reflection rectangular waveguide method. A lossy carbon-loaded Acrylonitrile Butadiene Styrene (ABS) polymer was selected to realize a matched load between 8 and 12 GHz. Two different types of terminations were realized by fused deposition modeling: a hybrid 3-D printed termination (metallic waveguide + pyramidal polymer absorber + metallic short circuit) and a full 3-D printed termination (self-consistent matched load). Voltage standing wave ratio of less than 1.075 and 1.025 were measured over X-band for the hybrid and full 3-D printed terminations, respectively. Power behavior of the full 3-D printed termination was investigated. A very linear evolution of reflected power as a function of incident power amplitude was observed at 10 GHz up to 11.5 W. These 3-D printed devices appear as a very low cost solution for the realization of microwave matched loads in rectangular waveguide technology.

3D printing for microwave: Materials characterization and application in the field of absorbers

In this study, the microwave properties of a wide range of materials, formed by two types of additive technologies (stereolithography apparatus and fused deposition modeling) were extracted in the X-band (8-12 GHz). ABS filled with carbon was chosen to realize a demonstrator. This high loss material was shaped in the form of a pyramid by 3D printing technology. By introducing it into a short-circuited waveguide, a matched load covering the whole X-band was realized (return loss <; -30 dB). The flexibility of these techniques and the availability of low cost commercial materials suggest many potential applications in the microwave range.

3D printed ferromagnetic composites for microwave applications

The use of 3D technology in the field of microwave electronics requires the development of new materials adapted to these applications. In this study, magnetic composites composed of polyethylene (PE) matrix filled with Nickel–Iron alloy (Ni81Fe19) are prepared using two elaboration devices: first, a propeller mixer for small quantity of samples, and then, a twin screw extruder able to produce higher samples amounts. Microstructural and rheological characterizations are suggested in order to study the feasibility of shaping PE/NiFe composites with 3D printer using Fused Deposition Modeling technique. A shear-thinning behavior with the dispersion of NiFe micrometric particles allows the use of 3D printer to shape final composites. A microwave characterization is also performed. Electromagnetic properties are predicted by the adjustment of a model based on mixing laws taking into account demagnetization effect and interactions between NiFe particles. The production of composite filaments and first printing tests are also presented.

Determination of Intrinsic and Induced Magnetic Anisotropies in Ni–Zn and Ni–Zn–Co Spinel Ferrites by Using Singular Point Detection Method and Their Comparison With FMR Method

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A simple process to obtain anisotropic self-biased magnets constituted of stacked barium ferrite single domain particles

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Mise en forme et caractérisation d’un Cyclo Polyoléfine pour une adaptation de la technique d’impression 3D aux matériaux hyperfréquences

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Additive technology applied to the realization of K-band microwave terminations: reproducibility improvement

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Mesure des champs d'anisotropie magnétocristallins de ferrites hexagonal et spinelle à l'aide de méthodes statique et dynamiques

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L'impression 3D pour les hyperfréquences : caractérisation EM et application dans le domaine des absorbants

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L’impression 3D pour les hyperfréquences : caractérisation de matériaux commerciaux et exemple d’application dans le domaine des absorbants

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