Micro-filters for medical applications and dielectric 5G antennas made of plastic materials: advanced micro-technologies and additive manufacturing processes for customized components with micro-features at micro-EDM e caratterizzazione, micro-injection moulding, mechatronic and prototype production labs of CNR-STIIMA Bari Lembo.

For years, CNR-STIIMA is in charge of investigating, optimizing and promoting micro-technologies in the process chain. The combined exploitation of micro-electro erosion and micro-injection molding plays a key role in conceiving and realizing innovative components exhibiting micro-sized features for critical areas of applications, such as the medical field. Moreover, the additive manufacturing processes involving polymers at show their potential micro-scale towards the rapid prototyping of novel 5G telecommunications devices, with3D geometries displaying micro-details. Although based on different processes, both micro-injection molding and additive manufacturing technologies, such as FDM and micro-SLA, use polymer materials, which display various and multipurpose characteristics and whose supply is easy and low cost.

Micro-electro erosion and micro-injection molding in the process chain for the production of polymer-based micro-components

When it comes to realizing components with challenging micro-sizes and high aspect ratio, combining micro-electro erosion and micro-injection molding in the process chain turns out to be a successful strategy. By means of electrical sparks, micro-electro erosion is capable of engraving into the metallic workpiece, such as a. mold, micro-featured shapes, as micro-cavities, micro-channels, protrusions characterizing the mirrored geometry of the final component. The micro-structured mold is then utilized for and in the micro-injection process, where, by proper control of material quantity, temperature and pressure, a piston injects the melted polymer. In this way, the process accomplishes the accurate reproduction of the final part through precise polymeric replicas of the geometry, as in the case of a micro-filter with micro-sized channels or micro-structured plates for medical applications.

Additive manufacturing technologies for 5G antennas: the creative design with high performance

Additive Manufacturing technologies (AM) have outstanding capabilities of producing devices with 3D geometries and freeform shapes, thus allowing their rapid prototyping and actualizing of the most creative and complex designs. In this frame, CNR-STIIMA in collaboration with the Polytechnic of Bari, has fabricated dielectric resonator antennas (DRA) for 5G telecommunications. The antenna designs are characterized by complex and bioinspired shapes with micro-sized features, and are realized by means of extrusion (FDM) and photopolymerization processes (SLA) which exploit suitable polymers (including also biodegradable ones such as polylactic acid-PLA) and resins, respectively. The use of such technologies and materials yields the rapid prototyping of high-performance antennas fulfilling the 5G standard requirements, especially large bandwidth, and high gain. The prototypes are also characterized by lightness and reduced material volumes, which make them suitable for aerospace applications, while the use of biodegradable polymers opens the path to a more eco-friendly impact on the environment.