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3D Printing for Hybrid Nanocomposites
Published in Ajit Behera, Tuan Anh Nguyen, Ram K. Gupta, Smart 3D Nanoprinting, 2023
Garima Mittal, Shiladitya Paul
3D components are printed by depositing liquid or paste material on a selected path in a layer-by-layer assembly. FFF is one of the extensively employed techniques for printing hybrid nanocomposites. Besides, due to the cost-efficient nature and easy scalability, this method is suitable for industrial production. The printing processability and properties of the printed component depend on various process parameters such as feed rate, print speed, material properties, inorganic-organic ratio and filler content. In FFF, hybrid nanocomposite filaments or pellets are automatically fed into a printing system with a predefined feeding rate, heated and extruded from the printing nozzle. Mainly thermoplastics such as acrylonitrile butadiene styrene (ABS), polystyrene (PS), polylactic acid (PLA), polycarbonate (PC) and nylon are printed using FFF. In a study, hybrid nanocomposite filaments of PLLA/n-HAp/bioactive glass were formed in two steps. At first, inorganic components (n-HAp/bioactive glass) were dispersed into an aqueous solution, followed by mixing with PLLA granules for homogeneous mixing of both parts. The obtained solution was dried for 12 h at 50 °C. Then, a twin-screw extruder was used to form hybrid filaments, where the composite granules were extruded, followed by palletisation and second-time extrusion for homogenous dispersion of all phases. These filaments showed excellent printability for the FFF 3D printing method [11].
3D-Printed Nanodevices of Pharmaceutical and Biomedical Relevance
Published in Suvardhan Kanchi, Rajasekhar Chokkareddy, Mashallah Rezakazemi, Smart Nanodevices for Point-of-Care Applications, 2022
FDM, also called fused filament fabrication (FFF), is an additive manufacturing technique where a 3D object is built by deposition of the melted polymer in a layer-by-layer manner (Figure 22.2). This is the most widely executed technique in 3D printing and was first patented and commercialized by Scott Crump in 1992 [18]. In this technique, thermoplastic polymer is fed into a nozzle which is heated up so the melted polymer in the semifluid state is extruded through a printing nozzle. The printer heads move and the extruded polymer is deposited as filament and gets solidified by cooling below its thermoplastic temperature. Then the subsequent layer of the polymer is deposited upon the first and thus the 3D structure is printed. Here, the build plate is present upon which the filament is formed and it moves down by printing layer upon layer [19].
Polymer Processing
Published in Anil Kumar, Rakesh K. Gupta, Fundamentals of Polymer Engineering, 2018
FFF is well-suited for niche areas, such as rapid prototyping, and also for part production characterized by low-volume, high-value, and/or intermittent demand. It is being used for everything from printing toys at home to printing flight hardware for legacy defense programs and commercial airplanes. To expand its use, FFF would need to be viable in application areas with higher volumes or rates or with lower part value. Some of the detracting items for the process are a relatively slow rate of production, limited part size, expensive and limited-selection materials, and historical data and engineering. The mechanical properties are poor compared to many of the traditional techniques, particularly in the Z direction. Creep and fatigue performance have not been extensively examined. The parts have ridges on the outside between layers, and internal voids are typically 8%–11%, both of which cause stress concentrations, which detract from high-strain properties like creep, fatigue, and impact resistance. This process also requires extensive post-processing for parts to satisfy surface aesthetics, permeability, chemical resistance, or biocompatible requirements.
Fused Filament Fabrication of cellular, lattice and porous mechanical metamaterials: a review
Published in Virtual and Physical Prototyping, 2023
Enrique Cuan-Urquizo, Rafael Guerra Silva
Although FFF is commonly considered as a good fit for prototyping and low-volume production it has several traits that make it a good option in manufacturing. In comparison to other AM technologies such as stereolithography (SLA) or selective laser sintering (SLS), FFF is not just cost-effective, but also eliminates the challenges and risks associated to the use of resins or powder. FFF is capable of printing diverse materials, including thermoplastics, elastomers, and combinations of different materials that include fiber and particle reinforced polymers. Even if resolution and accuracy are inferior to those of other AM processes, it can produce parts of good quality, as well as complex self-supporting geometries, with mechanical properties comparable to those of SLS and SLA parts.
Use of additive manufacturing for the fabrication of cellular and lattice materials: a review
Published in Materials and Manufacturing Processes, 2021
Esmeralda Uribe-Lam, Cecilia D. Treviño-Quintanilla, Enrique Cuan-Urquizo, Oscar Olvera-Silva
Fused filament fabrication (FFF) is an additive-manufacturing process based on the fabrication of 3D objects by means of extruded layers. Such layers could be of various materials, mainly polymers, for example polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS), polycarbonate (PC), [16] poly-ether-ether-ketone (PEEK), [17,18] ULTEM 9085,[19] and metals.[20] Additionally, fused filament fabrication machines have been upgraded so that 3D objects are made from composite materials, [21,22] for example by reinforced polymers including carbon fibers, [23,24] and bimodal manufacturing incorporating fused filament fabrication and electrospinning.[25]
Parameter effects and process modelling of Polyamide 12 3D-printed parts strength and toughness
Published in Materials and Manufacturing Processes, 2022
N. Vidakis, M. Petousis, J.D. Kechagias
Fused Filament Fabrication (FFF) process is a fully controllable 3D Printing (3DP) manufacturing process that deposits mainly polymeric materials in raster form progressively bottom-to-up layer-by-layer.[1] The quality of the FFF parts, which is evaluated by parameters of the build parts, such as mechanical response, toughness, dimensional and shape accuracy, and surface quality, is influenced by the 3DP Process Parameters (PP).[2] The 3DP-PPs variability affect the 3DP Process Quality (PQ) differently, making the process control a challenging assignment.[3,4] The proposed steps on selecting the PPs according to each material selection in FFF follows: