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Benza, Donald W.

Publications and source records attributed to Benza, Donald W..

Fused Filament Fabrication of Polycarbonate in a Reactive Atmosphere

Fused Filament Fabrication (FFF) has become extremely useful in various industries, particularly when complex parts are needed in low volumes. However, the material properties available in FFF polymers are limited in scope. The properties of a FFF part can be changed in multiple ways. This study explores changing the bulk properties of a part by affecting each layer as it prints. Prior work has demonstrated the feasibility of altering polymer properties by layerwise exposure to a liquid chemical, but properties have never been modified in situ using a reactive gas. Here, FFF is done in the presence of a reactive gas. Specifically, the part is printed with polycarbonate in a reactive atmosphere of ozone and ultra-violet light. It was found that as each layer is exposed to a reactive gas, the bulk properties of the part change. A visual chemical change was seen, as well as confirmation of the reaction through Fourier transform infrared spectroscopy attenuated total reflectance. The change in mechanical properties was measured through Dynamic Mechanical Analysis shear tests, showing a bulk change can be efficiently produced through FFF in a reactive atmosphere.

36 MATERIALS SCIENCE↗

Laser-induced graphene/graphite antenna

The present disclosure is directed to an antenna that includes a substrate and a graphene or graphite layer positioned on at least a portion of the substrate. The graphene or graphite layer includes a first zone having a first thickness along a vertical direction of the antenna and a second zone having a second thickness along the vertical direction of the antenna. The second thickness is less than the first thickness such that the second zone has a greater electrical resistance than the first zone.

Benza, Donald W.↗

Laser induced graphene/graphite antenna

The present disclosure is directed to an antenna that includes a substrate and a graphene or graphite layer positioned on at least a portion of the substrate. The graphene or graphite layer includes a first zone having a first thickness along a vertical direction of the antenna and a second zone having a second thickness along the vertical direction of the antenna. The second thickness is less than the first thickness such that the second zone has a greater electrical resistance than the first zone.

42 ENGINEERING↗