Use of polymer concrete for large-scale 3D printing

Purpose This paper aims to focus on the evaluation of a polymer concrete as a three-dimensional (3D) printing material. An associated company has developed plastic concrete made from reused unrecyclable plastic waste. Its intended use is as a construction material. Design/methodology/approach The concrete mix, called PolyBet, composed of polypropylene and glass sand, is printed by the fused deposition modelling process. The process of material and parameter selection is described. The mechanical properties of the filled material were compared to its cast state. Samples were made from castings and two different orientations of 3D-printed parts. Three-point flex tests were carried out, and the area of the break was examined. Computed tomography of the samples was carried out. Findings The influence of the 3D printing process on the material was evaluated. The mechanical performance of the longitudinal samples was close to the cast state. There was a difference in the failure mode between the states, with cast parts exhibiting a tougher behaviour, with fractures propagating in a stair-like manner. The 3D-printed samples exhibited high degrees of porosity. Originality/value The results suggest that the novel material is a good fit for 3D printing, with little to no degradation caused by the process. Layer adhesion was shown to be excellent, with negligible effect on the finished part for the longitudinal orientation. That means, if large-scale testing of buildability is successful, the material is a good fit for additive manufacturing of building components and other large-scale structures.

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FDM 3D printing method utility assessment in small RC aircraft design

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-07-2018-0189 ◽

2019 ◽

Vol 91 (6) ◽

pp. 865-872 ◽

Cited By ~ 4

Author(s):

Igor Skawiński ◽

Tomasz Goetzendorf-Grabowski

Keyword(s):

3D Printing ◽

Aircraft Design ◽

Cost Effective ◽

Fused Deposition Modelling ◽

Thin Wall ◽

Good Reliability ◽

Content Type ◽

Fused Deposition ◽

Wall Structures ◽

3D Printed

Purpose The purpose of this paper is to investigate the possibility of manufacturing fused deposition modelling (FDM) 3D printed structures such as wings or fuselages for small remote control (RC) air craft and mini unmaned aerial vehicles (UAVs). Design/methodology/approach Material tests, design assumptions and calculations were verified by designing and manufacturing a small radio-controlled motor-glider using as many printed parts as possible and performing test flights. Findings It is possible to create an aircraft with good flight characteristics using FDM 3D printed parts. Current level of technology allows for reasonably fast manufacturing of 3D printed aircraft with good reliability and high success ratio of prints; however, only some of the materials are suitable for printing thin wall structures such as wings. Practical implications The paper proves that apart from currently popular small RC aircraft structural materials such as composites, wood and foam, there is also printed plastic. Moreover, 3D printing is highly competitive in some aspects such as first unit production time or production cost. Originality/value The presented manufacturing technique can be useful for quick and cost-effective creating scale prototypes of the aircraft for performing test flights.

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Evaluation of Tensile Properties and Damage of Continuous Fibre Reinforced 3D-Printed Parts

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.774.161 ◽

2018 ◽

Vol 774 ◽

pp. 161-166 ◽

Cited By ~ 8

Author(s):

Octavio Andrés González-Estrada ◽

Alberto Pertuz ◽

Jabid E. Quiroga Mendez

Keyword(s):

3D Printing ◽

Tensile Properties ◽

Mechanical Performance ◽

Volume Fraction ◽

Three Dimensional ◽

Tensile Tests ◽

Fused Deposition Modelling ◽

Printing Process ◽

Fused Deposition ◽

3D Printed

Three-dimensional (3D) printing technology has been traditionally used for the production of prototypes. Recently, developments in 3D printing using Fused Deposition Modelling (FDM) and reinforcement with continuous fibres (fiberglass and carbon fibre), have allowed the manufacture of functional prototypes, considerably improving the mechanical performance of the composite parts. In this work, we characterise the elastic tensile properties of fibre reinforced specimens, considering the variation of several parameters available during the printing process: fibre orientation, volume fraction, fill pattern, reinforcement distribution. Tensile tests were performed according to ASTM D638 to obtain Young’s modulus and ultimate strength for different material configurations available during the printing process. We also perform a fractographic analysis using Scanning Electron Microscopy (SEM) to give an insight of the failure mechanisms present in the specimens.

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3D Printing of Thermo-Sensitive Drugs

Pharmaceutics ◽

10.3390/pharmaceutics13091524 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1524

Author(s):

Sadikalmahdi Abdella ◽

Souha H. Youssef ◽

Franklin Afinjuomo ◽

Yunmei Song ◽

Paris Fouladian ◽

...

Keyword(s):

3D Printing ◽

Three Dimensional ◽

Fused Deposition Modelling ◽

Future Directions ◽

Digital Light Processing ◽

Fused Deposition ◽

Printing Technique ◽

3D Printed ◽

Semi Solid ◽

Selection Of

Three-dimensional (3D) printing is among the rapidly evolving technologies with applications in many sectors. The pharmaceutical industry is no exception, and the approval of the first 3D-printed tablet (Spiratam®) marked a revolution in the field. Several studies reported the fabrication of different dosage forms using a range of 3D printing techniques. Thermosensitive drugs compose a considerable segment of available medications in the market requiring strict temperature control during processing to ensure their efficacy and safety. Heating involved in some of the 3D printing technologies raises concerns regarding the feasibility of the techniques for printing thermolabile drugs. Studies reported that semi-solid extrusion (SSE) is the commonly used printing technique to fabricate thermosensitive drugs. Digital light processing (DLP), binder jetting (BJ), and stereolithography (SLA) can also be used for the fabrication of thermosensitive drugs as they do not involve heating elements. Nonetheless, degradation of some drugs by light source used in the techniques was reported. Interestingly, fused deposition modelling (FDM) coupled with filling techniques offered protection against thermal degradation. Concepts such as selection of low melting point polymers, adjustment of printing parameters, and coupling of more than one printing technique were exploited in printing thermosensitive drugs. This systematic review presents challenges, 3DP procedures, and future directions of 3D printing of thermo-sensitive formulations.

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3D-Printable PP/SEBS Thermoplastic Elastomeric Blends: Preparation and Properties

Polymers ◽

10.3390/polym11020347 ◽

2019 ◽

Vol 11 (2) ◽

pp. 347 ◽

Cited By ~ 18

Author(s):

Shib Banerjee ◽

Stephen Burbine ◽

Nischay Kodihalli Shivaprakash ◽

Joey Mead

Keyword(s):

3D Printing ◽

Carbon Black ◽

Computer Aided Design ◽

Fused Deposition Modeling ◽

Mechanical Performance ◽

Polymeric Materials ◽

Fused Deposition ◽

3D Printed ◽

Injection Molded ◽

Preferential Location

Currently, material extrusion 3D printing (ME3DP) based on fused deposition modeling (FDM) is considered a highly adaptable and efficient additive manufacturing technique to develop components with complex geometries using computer-aided design. While the 3D printing process for a number of thermoplastic materials using FDM technology has been well demonstrated, there still exists a significant challenge to develop new polymeric materials compatible with ME3DP. The present work reports the development of ME3DP compatible thermoplastic elastomeric (TPE) materials from polypropylene (PP) and styrene-(ethylene-butylene)-styrene (SEBS) block copolymers using a straightforward blending approach, which enables the creation of tailorable materials. Properties of the 3D printed TPEs were compared with traditional injection molded samples. The tensile strength and Young’s modulus of the 3D printed sample were lower than the injection molded samples. However, no significant differences could be found in the melt rheological properties at higher frequency ranges or in the dynamic mechanical behavior. The phase morphologies of the 3D printed and injection molded TPEs were correlated with their respective properties. Reinforcing carbon black was used to increase the mechanical performance of the 3D printed TPE, and the balancing of thermoplastic elastomeric and mechanical properties were achieved at a lower carbon black loading. The preferential location of carbon black in the blend phases was theoretically predicted from wetting parameters. This study was made in order to get an insight to the relationship between morphology and properties of the ME3DP compatible PP/SEBS blends.

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Photonic curing of silver paths on 3D printed polymer substrate

Circuit World ◽

10.1108/cw-11-2018-0084 ◽

2019 ◽

Vol 45 (1) ◽

pp. 9-14

Author(s):

Jakub Krzeminski ◽

Bartosz Blicharz ◽

Andrzej Skalski ◽

Grzegorz Wroblewski ◽

Małgorzata Jakubowska ◽

...

Keyword(s):

Polymer Substrate ◽

Fused Deposition Modelling ◽

Content Type ◽

Fused Deposition ◽

Photonic Curing ◽

Structural Electronics ◽

Jet Printing ◽

3D Printed ◽

Aerosol Jet Printing ◽

Photonic Sintering

Purpose Despite almost limitless possibilities of rapid prototyping, the idea of 3D printed fully functional electronic device still has not been fulfilled – the missing point is a highly conductive material suitable for this technique. The purpose of this paper is to present the usage of the photonic curing process for sintering highly conductive paths printed on the polymer substrate. Design/methodology/approach This paper evaluates two photonic curing processes for the conductive network formulation during the additive manufacturing process. Along with the xenon flash sintering for aerosol jet-printed paths, this paper examines rapid infrared sintering for thick-film and direct write techniques. Findings This paper proves that the combination of fused deposition modeling, aerosol jet printing or paste deposition, along with photonic sintering, is suitable to obtain elements with low resistivity of 3,75·10−8 Ωm. Presented outcomes suggest the solution for fabrication of the structural electronics systems for daily-use applications. Originality/value The combination of fused deposition modelling (FDM) and aerosol jet printing or paste deposition used with photonic sintering process can fill the missing point for highly conductive materials for structural electronics.

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Surface Preparation and Treatment for Large-Scale 3D-Printed Composite Tooling Coating Adhesion

Coatings ◽

10.3390/coatings8120457 ◽

2018 ◽

Vol 8 (12) ◽

pp. 457 ◽

Cited By ~ 3

Author(s):

Philipp Sauerbier ◽

James Anderson ◽

Douglas Gardner

Keyword(s):

Additive Manufacturing ◽

Large Scale ◽

Lower Cost ◽

Numerical Control ◽

Fused Deposition Modelling ◽

Filler Materials ◽

Coating Adhesion ◽

Fused Deposition ◽

Composite Tooling ◽

3D Printed

Recent advances in large-scale thermoplastic additive manufacturing (AM), using fused deposition modelling (FDM), have shown that the technology can effectively produce large aerospace tools with common feed stocks, costing 2.3 $/kg, such as a 20% carbon-filled acrylonitrile butadiene styrene (ABS). Large-scale additive manufacturing machines have build-volumes in the range of cubic meters and use commercially available pellet feedstock thermoplastics, which are significantly cheaper (5–10 $/kg) than the filament feedstocks for desktop 3D printers (20–50 $/kg). Additionally, large-scale AM machines have a higher material throughput on the order of 50 kg/h. This enables the cost-efficient tool production for several industries. Large-scale 3D-printed tooling will be computerized numerical control (CNC)-machined and -coated, to provide a surface suitable for demolding the composite parts. This paper outlines research undertaken to review and improve the adhesion of the coating systems to large, low-cost AM composite tooling, for marine or infrastructure composite applications. Lower cost tooling systems typically have a lower dimensional accuracy and thermal operating requirements than might be required for aerospace tooling. As such, they can use lower cost commodity grade thermoplastics. The polymer systems explored in the study included polypropylene (PP), styrene-maleic anhydride (SMA), and polylactic acid (PLA). Bio-based filler materials were used to reduce cost and increase the strength and stiffness of the material. Fillers used in the study included wood flour, at 30% by weight and spray-dried cellulose nano-fibrils, at 20% by weight. Applicable adhesion of the coating was achieved with PP, after surface treatment, and untreated SMA and PLA showed desirable coating adhesion results. PLA wood-filled composites offered the best properties for the desired application and, furthermore, they have environment-friendly advantages.

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Mechanical Properties of Diamond Schwarzites: From Atomistic Models to 3D-Printed Structures

MRS Advances ◽

10.1557/adv.2020.175 ◽

2020 ◽

Vol 5 (33-34) ◽

pp. 1775-1781 ◽

Cited By ~ 1

Author(s):

Levi C. Felix ◽

Vladimir Gaál ◽

Cristiano F. Woellner ◽

Varlei Rodrigues ◽

Douglas S. Galvao

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Uniaxial Compression ◽

Chemical Vapour ◽

Md Simulations ◽

Atomic Model ◽

Fused Deposition Modelling ◽

Fused Deposition ◽

Structural Applications ◽

3D Printed

ABSTRACTTriply Periodic Minimal Surfaces (TPMS) possess locally minimized surface area under the constraint of periodic boundary conditions. Different families of surfaces were obtained with different topologies satisfying such conditions. Examples of such families include Primitive (P), Gyroid (G) and Diamond (D) surfaces. From a purely mathematical subject, TPMS have been recently found in materials science as optimal geometries for structural applications. Proposed by Mackay and Terrones in 1991, schwarzites are 3D crystalline porous carbon nanocrystals exhibiting a TPMS-like surface topology. Although their complex topology poses serious limitations on their synthesis with conventional nanoscale fabrication methods, such as Chemical Vapour Deposition (CVD), schwarzites can be fabricated by Additive Manufacturing (AM) techniques, such as 3D Printing. In this work, we used an optimized atomic model of a schwarzite structure from the D family (D8bal) to generate a surface mesh that was subsequently used for 3D-printing through Fused Deposition Modelling (FDM). This D schwarzite was 3D-printed with thermoplastic PolyLactic Acid (PLA) polymer filaments. Mechanical properties under uniaxial compression were investigated for both the atomic model and the 3D-printed one. Fully atomistic Molecular Dynamics (MD) simulations were also carried out to investigate the uniaxial compression behavior of the D8bal atomic model. Mechanical testings were performed on the 3D-printed schwarzite where the deformation mechanisms were found to be similar to those observed in MD simulations. These results are suggestive of a scale-independent mechanical behavior that is dominated by structural topology.

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Mechanical properties and water absorption of surface modified ABS 3D printed by fused deposition modelling

Rapid Prototyping Journal ◽

10.1108/rpj-04-2016-0057 ◽

2018 ◽

Vol 24 (1) ◽

pp. 195-203 ◽

Cited By ~ 18

Author(s):

Marco Leite ◽

André Varanda ◽

António Relógio Ribeiro ◽

Arlindo Silva ◽

Maria Fátima Vaz

Keyword(s):

Mechanical Properties ◽

Absorption Coefficient ◽

Water Absorption ◽

Dimensional Stability ◽

Open Porosity ◽

Fused Deposition Modelling ◽

Content Type ◽

Fused Deposition ◽

Tension Properties ◽

3D Printed

Purpose The purpose of this paper is to investigate the effect of a sealing protective treatment on the water absorption and mechanical properties of acrylonitrile butadiene styrene (ABS)-printed parts by fused deposition modelling. Protective products include aqueous acetone solutions with different concentrations, polyurethane wood sealer and aqueous acrylic-based varnish. Design/methodology/approach Open porosity was estimated by the absorption coefficient and the total amount of water retained, obtained from water absorption tests. Mechanical characterization was performed by compressive and tensile tests. Different specimens with different build directions and raster angles were used. Findings The treatments with acetone solutions were not effective in reducing the porosity of ABS parts, as the amount of acetone that reduces effectively the porosity will also affect the sample dimensional stability. The polyurethane treatment was found to reduce the absorption coefficient, but the maximum water content and the open porosity remain almost unchanged in comparison with the ones obtained for untreated specimens. The treatment with an acrylic-based varnish was found to preserve the dimensional stability of the specimens, to reduce the open porosity and to maintain the compression and tension properties of the specimens in different build directions and raster angles. Originality/value Surface modification for water tight applications of ABS 3D printing parts enables new designs where both sealing and the preservation of mechanical properties are important. As per the knowledge of the authors, the water absorption and the mechanical behaviour of ABS 3D printed parts, before and after treatment, were not previously investigated.

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Ten guidelines for the design of non-assembly mechanisms: The case of 3D-printed prosthetic hands

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411918794734 ◽

2018 ◽

Vol 232 (9) ◽

pp. 962-971 ◽

Cited By ~ 8

Author(s):

Juan Sebastian Cuellar ◽

Gerwin Smit ◽

Amir A Zadpoor ◽

Paul Breedveld

Keyword(s):

Developing Countries ◽

3D Printing ◽

Fused Deposition Modelling ◽

Prosthetic Hand ◽

Prosthetic Devices ◽

Hand Prosthesis ◽

Fused Deposition ◽

Prosthetic Hands ◽

Design Considerations ◽

3D Printed

In developing countries, prosthetic workshops are limited, difficult to reach, or even non-existent. Especially, fabrication of active, multi-articulated, and personalized hand prosthetic devices is often seen as a time-consuming and demanding process. An active prosthetic hand made through the fused deposition modelling technology and fully assembled right after the end of the 3D printing process will increase accessibility of prosthetic devices by reducing or bypassing the current manufacturing and post-processing steps. In this study, an approach for producing active hand prosthesis that could be fabricated fully assembled by fused deposition modelling technology is developed. By presenting a successful case of non-assembly 3D printing, this article defines a list of design considerations that should be followed in order to achieve fully functional non-assembly devices. Ten design considerations for additive manufacturing of non-assembly mechanisms have been proposed and a design case has been successfully addressed resulting in a fully functional prosthetic hand. The hand prosthesis can be 3D printed with an inexpensive fused deposition modelling machine and is capable of performing different types of grasping. The activation force required to start a pinch grasp, the energy required for closing, and the overall mass are significantly lower than body-powered commercial prosthetic hands. The results suggest that this non-assembly design may be a good alternative for amputees in developing countries.

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Three-dimensional Printing Versus Conventional Machining in the Creation of a Meatal Urethral Dilator: a Cost and Mechanical Strength Analysis

10.21203/rs.3.rs-28817/v1 ◽

2020 ◽

Author(s):

Michael Yue-Cheng Chen ◽

Jacob Skewes ◽

Ryan Daley ◽

Maria Ann Woodruff ◽

Nicholas John Rukin

Keyword(s):

3D Printing ◽

Three Dimensional ◽

Patient Specific ◽

Strength Analysis ◽

Fused Deposition Modelling ◽

3D Printer ◽

Current Time ◽

Fused Deposition ◽

3D Printed ◽

Conventional Machining

Abstract BackgroundThree-dimensional (3D) printing is a promising technology but the limitations are often poorly understood. We compare different 3D printingmethods with conventional machining techniques in manufacturing meatal urethral dilators which were recently removed from the Australian market. MethodsA prototype dilator was 3D printed vertically orientated on a low cost fused deposition modelling (FDM) 3D printer in polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS). It was also 3D printed horizontally orientated in ABS on a high-end FDM 3D printer with soluble support material, as well as on a SLS 3D printer in medical nylon. The dilator was also machined in stainless steel using a lathe. All dilators were tested mechanically in a custom rig by hanging calibrated weights from the handle until the dilator snapped. ResultsThe horizontally printed ABS dilator experienced failure at a greater load than the vertically printed PLA and ABS dilators respectively (503g vs 283g vs 163g, p < 0.001). The SLS nylon dilator and machined steel dilator did not fail. The steel dilator is most expensive with a quantity of five at 98 USD each, but this decreases to 30 USD each for a quantity of 1000. In contrast, the cost for the SLS dilator is 33 USD each for five and 27 USD each for 1000. ConclusionsAt the current time 3D printing is not a replacement for conventional manufacturing. 3D printing is best used for patient-specific parts, prototyping or manufacturing complex parts that have additional functionality that cannot otherwise beachieved.

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