Conductive Electrifi and Nonconductive NinjaFlex Filaments based Flexible Microstrip Antenna for Changing Conformal Surface Applications

As the usage of wireless technology grows, it demands more complex architectures and conformal geometries, making the manufacturing of radio frequency (RF) systems challenging and expensive. The incorporation of emerging alternative manufacturing technologies, like additive manufacturing (AM), could consequently be a unique and cost-effective solution for flexible RF and microwave circuits and devices. This work presents manufacturing methodologies of 3D-printed conformal microstrip antennas made of a commercially available conductive filament, Electrifi, as the conductive trace on a commercially available nonconductive filament, NinjaFlex, as the substrate using the fused filament fabrication (FFF) method of AM technology. Additionally, a complete high frequency characterization of the prototyped antenna was studied and presented here through a comparative analysis between full-wave simulation and measurements in a fully calibrated anechoic chamber. The prototyped antenna measures 65.55 × 55.55 × 1.2 mm3 in size and the measured results show that the 3D-printed Electrifi based patch antenna achieved very good impedance matching at a resonant frequency of 2.4 GHz and a maximum antenna gain of −2.78 dBi. Finally, conformality performances of the developed antenna were demonstrated by placing the antenna prototype on five different cylindrical curved surfaces for possible implementation in flexible electronics, smart communications, and radar applications.

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Metallization of Thermoplastic Polymers and Composites 3D Printed by Fused Filament Fabrication

Technologies ◽

10.3390/technologies9030049 ◽

2021 ◽

Vol 9 (3) ◽

pp. 49

Author(s):

Alessia Romani ◽

Andrea Mantelli ◽

Paolo Tralli ◽

Stefano Turri ◽

Marinella Levi ◽

...

Keyword(s):

Physical Vapor Deposition ◽

Test Sample ◽

Tensile Tests ◽

Layer By Layer ◽

Post Processing ◽

Thermoplastic Polymers ◽

Fused Filament Fabrication ◽

Scanning Calorimetry ◽

3D Printed ◽

Manufacturing Technologies

Fused filament fabrication allows the direct manufacturing of customized and complex products although the layer-by-layer appearance of this process strongly affects the surface quality of the final parts. In recent years, an increasing number of post-processing treatments has been developed for the most used materials. Contrarily to other additive manufacturing technologies, metallization is not a common surface treatment for this process despite the increasing range of high-performing 3D printable materials. The objective of this work is to explore the use of physical vapor deposition sputtering for the chromium metallization of thermoplastic polymers and composites obtained by fused filament fabrication. The thermal and mechanical properties of five materials were firstly evaluated by means of differential scanning calorimetry and tensile tests. Meanwhile, a specific finishing torture test sample was designed and 3D printed to perform the metallization process and evaluate the finishing on different geometrical features. Furthermore, the roughness of the samples was measured before and after the metallization, and a cost analysis was performed to assess the cost-efficiency. To sum up, the metallization of five samples made with different materials was successfully achieved. Although some 3D printing defects worsened after the post-processing treatment, good homogeneity on the finest details was reached. These promising results may encourage further experimentations as well as the development of new applications, i.e., for the automotive and furniture fields.

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3D-Printed Lab-on-a-Chip Diagnostic Systems-Developing a Safe-by-Design Manufacturing Approach

Micromachines ◽

10.3390/mi10120825 ◽

2019 ◽

Vol 10 (12) ◽

pp. 825

Author(s):

Panagiotis Karayannis ◽

Fotini Petrakli ◽

Anastasia Gkika ◽

Elias P. Koumoulos

Keyword(s):

Effective Means ◽

Ultrafine Particle ◽

Lab On A Chip ◽

Cost Effective ◽

Diagnostic Systems ◽

Fused Filament Fabrication ◽

Device Development ◽

Volatile Organic ◽

3D Printed ◽

Safe By Design

The aim of this study is to provide a detailed strategy for Safe-by-Design (SbD) 3D-printed lab-on-a-chip (LOC) device manufacturing, using Fused Filament Fabrication (FFF) technology. First, the applicability of FFF in lab-on-a-chip device development is briefly discussed. Subsequently, a methodology to categorize, identify and implement SbD measures for FFF is suggested. Furthermore, the most crucial health risks involved in FFF processes are examined, placing the focus on the examination of ultrafine particle (UFP) and Volatile Organic Compound (VOC) emission hazards. Thus, a SbD scheme for lab-on-a-chip manufacturing is provided, while also taking into account process optimization for obtaining satisfactory printed LOC quality. This work can serve as a guideline for the effective application of FFF technology for lab-on-a-chip manufacturing through the safest applicable way, towards a continuous effort to support sustainable development of lab-on-a-chip devices through cost-effective means.

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3D-Printed Drug Delivery Systems: The Effects of Drug Incorporation Methods on Their Release and Antibacterial Efficiency

Materials ◽

10.3390/ma13153364 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3364

Author(s):

Bahaa Shaqour ◽

Inés Reigada ◽

Żaneta Górecka ◽

Emilia Choińska ◽

Bart Verleije ◽

...

Keyword(s):

Drug Delivery ◽

3D Printing ◽

Drug Delivery Systems ◽

Drug Distribution ◽

Delivery Systems ◽

Solvent Casting ◽

Fused Filament Fabrication ◽

3D Printed ◽

Manufacturing Technologies ◽

Drug Incorporation

Additive manufacturing technologies have been widely used in the medical field. More specifically, fused filament fabrication (FFF) 3D-printing technology has been thoroughly investigated to produce drug delivery systems. Recently, few researchers have explored the possibility of directly 3D printing such systems without the need for producing a filament which is usually the feedstock material for the printer. This was possible via direct feeding of a mixture consisting of the carrier polymer and the required drug. However, as this direct feeding approach shows limited homogenizing abilities, it is vital to investigate the effect of the pre-mixing step on the quality of the 3D printed products. Our study investigates the two commonly used mixing approaches—solvent casting and powder mixing. For this purpose, polycaprolactone (PCL) was used as the main polymer under investigation and gentamicin sulfate (GS) was selected as a reference. The produced systems’ efficacy was investigated for bacterial and biofilm prevention. Our data show that the solvent casting approach offers improved drug distribution within the polymeric matrix, as was observed from micro-computed topography and scanning electron microscopy visualization. Moreover, this approach shows a higher drug release rate and thus improved antibacterial efficacy. However, there were no differences among the tested approaches in terms of thermal and mechanical properties.

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3D Printed Lab-on-a-Chip Diagnostic Systems - Developing a Safe-by-Design Manufacturing Approach

10.20944/preprints201911.0001.v1 ◽

2019 ◽

Author(s):

Panagiotis Karayannis ◽

Fotini Petrakli ◽

Anastasia Gkika ◽

Elias Koumoulos

Keyword(s):

Effective Means ◽

Ultrafine Particle ◽

Lab On A Chip ◽

Cost Effective ◽

Diagnostic Systems ◽

Fused Filament Fabrication ◽

Device Development ◽

Volatile Organic ◽

3D Printed ◽

Safe By Design

The aim of this study is to provide a detailed strategy for Safe-by-Design (SbD) 3D printed lab-on-a-chip (LOC) device manufacturing, using Fused Filament Fabrication (FFF) technology. At first, the applicability of FFF in lab-on-a-chip device development is briefly discussed. Subsequently, a methodology to categorize, identify and implement SbD measures for FFF is suggested. Furthermore, the most crucial health risks involved in FFF processes are examined, placing the focus on the examination of ultrafine particle (UFP) and Volatile Organic Compound (VOC) emission hazards. Thus, a SbD scheme for lab-on-a-chip manufacturing is provided, while also taking into account process optimization for obtaining satisfactory printed LOC quality. This work can serve as a guideline for the effective application of FFF technology for lab-on-a-chip manufacturing through the safest applicable way, towards a continuous effort to support sustainable development of lab-on-a-chip devices through cost-effective means.

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An Overview on Personal Protective Equipment (PPE) Fabricated with Additive Manufacturing Technologies in the Era of COVID-19 Pandemic

Polymers ◽

10.3390/polym12112703 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2703 ◽

Cited By ~ 1

Author(s):

Szilard Rendeki ◽

Balint Nagy ◽

Matyas Bene ◽

Attila Pentek ◽

Luca Toth ◽

...

Keyword(s):

Additive Manufacturing ◽

Open Source ◽

Personal Protective Equipment ◽

Face Mask ◽

Protective Equipment ◽

Fused Filament Fabrication ◽

Small Series ◽

Source Models ◽

3D Printed ◽

Manufacturing Technologies

Different additive manufacturing technologies have proven effective and useful in remote medicine and emergency or disaster situations. The coronavirus disease 2019 (COVID-19) disease, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus, has had a huge impact on our society, including in relation to the continuous supply of personal protective equipment (PPE). The aim of the study is to give a detailed overview of 3D-printed PPE devices and provide practical information regarding the manufacturing and further design process, as well as describing the potential risks of using them. Open-source models of a half-face mask, safety goggles, and a face-protecting shield are evaluated, considering production time, material usage, and cost. Estimations have been performed with fused filament fabrication (FFF) and selective laser sintering (SLS) technology, highlighting the material characteristics of polylactic acid (PLA), polyamide, and a two-compound silicone. Spectrophotometry measurements of transparent PMMA samples were performed to determine their functionality as goggles or face mask parts. All the tests were carried out before and after the tetra-acetyl-ethylene-diamine (TAED)-based disinfection process. The results show that the disinfection has no significant effect on the mechanical and structural stability of the used polymers; therefore, 3D-printed PPE is reusable. For each device, recommendations and possible means of development are explained. The files of the modified models are provided. SLS and FFF additive manufacturing technology can be useful tools in PPE development and small-series production, but open-source models must be used with special care.

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On the Influence of Manufacturing Strategy of 3D-Printed Polymer Substrates on Cold Spray Deposition

10.25518/esaform21.3003 ◽

2021 ◽

Author(s):

Antonio Viscusi ◽

Antonello Astarita ◽

Domenico Borrelli ◽

Antonio Caraviello ◽

Luigi Carrino ◽

...

Keyword(s):

Cold Spray ◽

Spray Deposition ◽

Deposition Process ◽

Potential Method ◽

Manufacturing Strategy ◽

Fused Filament Fabrication ◽

Research Activity ◽

Aluminum Powders ◽

3D Printed ◽

Manufacturing Technologies

PMCs are anisotropic and heterogeneous structures with excellent performances in terms of mechanical strength and stiffness, coupled with reduced weight, widely used in engineering sectors. The use of PMCs can be further extended by improving their surface properties such as electrical conductivity, erosion, radiation and lightning protection. In this context, the surface metallization seems to be best solution. In particular, the cold spray (CS) technique candidates as a potential method for the manufacturing of a metal coating on PMCs’ surface. However, the design and the manufacturing methods of PMCs can play a crucial role for an effective metallization through CS. The additive manufacturing technologies for composite materials can be used to manufacture customized reinforced polymer-based panels, like PMCs; the most common method for printing them is the Fused Filament Fabrication (FFF) technique which relies on the thermal extrusion of a thermoplastic feedstock from a mobile heated nozzle. Therefore, this research activity aims to manufacture customized PMCs panels by using FFF technology for the substrate and the cold spray technique for the metallization in order to study the influence of the substrate manufacturing strategy on CS deposition process. For this purpose, three kind of 3D-printed PMCs were manufactured through the FFF technology by varying the percentage fill of the Onyx polymeric matrix and aluminum powders were sprayed on the substrates with a low-pressure cold spray (LPCS) system; both FFF and CS process parameters were varied to study the process in its wholeness. Microscope analyses were carried out to analyze the influence of the manufacturing strategy on the coating quality.

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Surface modification of fused filament fabrication (FFF) 3D printed substrates by inkjet printing polyimide for printed electronics

Additive Manufacturing ◽

10.1016/j.addma.2020.101544 ◽

2020 ◽

Vol 36 ◽

pp. 101544

Author(s):

Devin J. Roach ◽

Christopher Roberts ◽

Janet Wong ◽

Xiao Kuang ◽

Joshua Kovitz ◽

...

Keyword(s):

Surface Modification ◽

Inkjet Printing ◽

Printed Electronics ◽

Fused Filament Fabrication ◽

3D Printed

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Evaluation of the Circularity of Recycled PLA Filaments for 3D Printers

Applied Sciences ◽

10.3390/app10248967 ◽

2020 ◽

Vol 10 (24) ◽

pp. 8967

Author(s):

Victor Gil Muñoz ◽

Luisa M. Muneta ◽

Ruth Carrasco-Gallego ◽

Juan de Juanes Marquez ◽

David Hidalgo-Carvajal

Keyword(s):

Circular Economy ◽

Protective Equipment ◽

Fused Filament Fabrication ◽

Circular Loop ◽

Material Supply ◽

3D Printers ◽

3D Printed ◽

Circular Economics ◽

High Level ◽

Additional Value

The circular economy model offers great opportunities to companies, as it not only allows them to capture additional value from their products and materials, but also reduce the fluctuations of price-related risks and material supply. These risks are present in all kind of businesses not based on the circular economy. The circular economy also enables economic growth without the need for more resources. This is because each unit has a higher value as a result of recycling and reuse of products and materials after use. Following this circular economics framework, the Polytechnic University of Madrid (Universidad Politécnica de Madrid, UPM) has adopted strategies aimed at improving the circularity of products. In particular, this article provides the result of obtaining recycled PLA filament from waste originating from university 3D FFF (fused filament fabrication) printers and waste generated by “Coronamakers” in the production of visors and parts for PPEs (Personal Protective Equipment) during the lockdown period of COVID-19 in Spain. This filament is used in the production of 3D printed parts that university students use in their classes, so the circular loop is closed. The obtained score of Material Circularity Indicator (MCI) of this material has been calculated, indicating its high level of circularity.

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Drivers of mechanical performance variance in 3D ‐printed fused filament fabrication parts: An Onyx FR case study

Polymer Composites ◽

10.1002/pc.26187 ◽

2021 ◽

Author(s):

Christine Ma ◽

Jessica Faust ◽

Joseph D. Roy‐Mayhew

Keyword(s):

Mechanical Performance ◽

Fused Filament Fabrication ◽

3D Printed

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Modeling Fused Filament Fabrication using Artificial Neural Networks

Production Engineering ◽

10.1007/s11740-021-01020-y ◽

2021 ◽

Author(s):

Paul Oehlmann ◽

Paul Osswald ◽

Juan Camilo Blanco ◽

Martin Friedrich ◽

Dominik Rietzel ◽

...

Keyword(s):

Real Time ◽

Large Scale ◽

Cost Effective ◽

Print Quality ◽

Ann Model ◽

Production Environment ◽

Fused Filament Fabrication ◽

Artificial Neural ◽

Using Data ◽

Artificial Neural Network Ann

AbstractWith industries pushing towards digitalized production, adaption to expectations and increasing requirements for modern applications, has brought additive manufacturing (AM) to the forefront of Industry 4.0. In fact, AM is a main accelerator for digital production with its possibilities in structural design, such as topology optimization, production flexibility, customization, product development, to name a few. Fused Filament Fabrication (FFF) is a widespread and practical tool for rapid prototyping that also demonstrates the importance of AM technologies through its accessibility to the general public by creating cost effective desktop solutions. An increasing integration of systems in an intelligent production environment also enables the generation of large-scale data to be used for process monitoring and process control. Deep learning as a form of artificial intelligence (AI) and more specifically, a method of machine learning (ML) is ideal for handling big data. This study uses a trained artificial neural network (ANN) model as a digital shadow to predict the force within the nozzle of an FFF printer using filament speed and nozzle temperatures as input data. After the ANN model was tested using data from a theoretical model it was implemented to predict the behavior using real-time printer data. For this purpose, an FFF printer was equipped with sensors that collect real time printer data during the printing process. The ANN model reflected the kinematics of melting and flow predicted by models currently available for various speeds of printing. The model allows for a deeper understanding of the influencing process parameters which ultimately results in the determination of the optimum combination of process speed and print quality.

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