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Determination of FDM Printer Settings with Regard to Geometrical Accuracy
... Polylactic acid (PLA) filament is considered as the printing material. PLA is one of the most commonly used materials because of its low cost, easily available, comparatively low toxicity and low print temperature [26,27]. PLA is also a biocompatible material which researchers have been using PLA as base material for making bioactive composite material [13]. ...
... This makes the layer height the most significant parameter among the other parameters in controlling dimensional accuracy. The result observed in this research is similar to the finding of Nidagundi et al. [33] and Polak et al. [26]. Among the four infill pattern types, the optimal infill pattern is observed with triangle infill pattern which is similar to the finding of Alafaghani et al. [34] where the dimensional accuracy is observed with diamond infill pattern. ...
... Hence, the optimal printing speed for dimensional accuracy is observed at 30 mm/s. It is in sync with the findings of Polak et al. [26] and Alafaghani et al. [34]. ...
Background
Fused deposition modelling (FDM) is a popular additive manufacturing technique with capability of producing complex and integrate shapes. One of the critical aspects of FDM is the dimensional accuracy of 3D (three-dimension) printed model, especially in medical science applications, as proper fit and function with human body can prevent patient’s discomfort, complication or even harm.
Objective
In this research work, the optimisation of print parameters: layer height, nozzle temperature, printing speed, infill pattern and infill density for improving the dimensional accuracy of distal femur bone, an irregular and complex shaped geometry is carried out using Taguchi’s method and to study its influence using ANOVA (analysis of variance).
Methodology
3D CAD (computer-aided design) model of the distal femur bone is generated from a CT (computerized tomography) scan using 3D slicer and its associated errors are corrected using Ansys SpaceClaim. The model is prepared for printing using Ultimaker Cura as per L 16 orthogonal array experimental layout where TEA (trans epicondylar axis), which is the distance between the most prominent point of the lateral and medial epicondyle, is set at 45° from X-axis in XY plane, i.e. diagonally on the plane of printing bed. It is then printed with PLA (polylactic acid) filament. Length along TEA is compared accordingly with 3D CAD model. Taguchi’s method of ‘smaller the better’ is applied for reducing deviation. Further, ANOVA analysis is done on the data set and a linear regression model is also developed.
Result
Through Taguchi’s method, the optimum parameters were found to be triangle for infill pattern, 200 °C for nozzle temperature, 30 mm/s for nozzle speed, 0.1 mm for layer height and 40% for infill density. ANOVA analysis shows that all parameters contribute significantly with layer height being the most influential parameter, followed by infill pattern, nozzle speed, nozzle temperature and infill density. Mathematical model through multiple linear regression method was developed with determination of coefficient value of 96.91% and standard residual value is within the acceptable range of ± 2 indicating that there is no outliner in the data.
... One of the most widely used technologies is Fused Deposition Modelling (FDM), a term trademarked by Stratasys [2], which is also known as Fused Filament Fabrication (FFF). This process entails passing a filament through an extruder, whereby the filament is softened to create the product layer by layer. ...
... In addition to the mechanical properties of the product, it has also been relevant to evaluate the extent to which the final geometry aligns with the desired design specifications. Accuracy [2], and precision [7] are two variables that have been also deemed important. ...
... Thermal history and deposition strategy are two major sources of inaccuracy [19]: indeed, as with FFF, a non-uniform temperature distribution can cause localised volumetric shrinkage, leading to component distortion [6,18,[20][21][22][23][24]. These effects can be limited by adjusting the build chamber temperature to match the softening temperature of the materials under examination [18,25]. The deposition strategy is crucial in determining the shrinkage directions and thus the accuracy of the parts [18,[26][27][28]. ...
Technological advances have increased the use of plastic-based additive manufacturing for production in a variety of industries that require high mechanical properties while maintaining geometric precision. The Arburg Plastic Freeformer (APF) process, unlike other filament-based technologies, uses standard plastic granules used in mass production in injection moulding machines. This study focuses on optimising the interaction of three critical process parameters: layer thickness (LT), droplet aspect ratio (DAR) and discharge rate (DR). Previous studies have mainly varied individual parameters to evaluate mechanical and geometrical properties. In contrast, this work analyses these parameters as a whole and evaluates their combined effects on residual porosity and geometric accuracy. APF relies heavily on supports to sustain the printed part, with a smaller achievable self-supporting overhang angle compared to the Fused Filament Fabrication (FFF) printing process. For this reason, this study investigates two compatible materials, ABS Terluran GP35 and a water-soluble PVP compound named Armat11. Cylindrical and cubic samples were 3D printed using different combinations of LT, DAR and DR. A total of 150 cubic samples were printed to assess the geometric dimensional accuracy and repeatability of printing in the plate position using permutations in the printing plate. Subsequently, 30 cylindrical samples were printed for micro-CT analysis, reconstructed by CT file segmentation and compared with the ideal CAD model, in addition to the characterisation of residual porosity. The results show that optimal combinations of LT, DAR and DR produce high density parts with repeatable geometric properties. In addition, a quantitative analytical model was developed to optimise arbitrary parameter sets. This comprehensive investigation provides important insights into the APF process and increases its potential for wider industrial applications.
... However, most FFF 3D printers have a cooling fan to cool down the fabricated part, which is a need while printing most materials to enhance print quality, especially for printing parts with fine details [31]. Yet, it should be noted that printing a highly detailed part with a big build volume is not viable in FFF, as bigger nozzle sizes are needed to be used as the build volume increases, limiting the print resolution. ...
Additive manufacturing (AM) is a technology based on the layer-by-layer production of parts. Fused filament fabrication (FFF) is one of the most cost-effective and popular AM techniques for the production of polymeric structures.
While the initial use of FFF was limited to thermoplastics such as PLA and ABS, recent advances enabled the printing of composite materials and structures for superior mechanical performance. Multi-material printing through dual-nozzle systems offers a unique opportunity towards this end, enabling the production of complex geometries composed of different types of polymers.
The first part of this thesis investigated one aspect of these composites – the mechanical behavior of the interfaces between two polymers. For this purpose, a range of PLA-TPU interfaces were produced by FFF, and the bonding between the two domains was investigated through mechanical testing and finite element modeling. The results demonstrated that the poor adhesion between the polymers can be significantly improved through the design of interlocking structures.
Another common approach to the printing of composite structures by FFF is the utilization of polymer-matrix filaments with reinforcements. Short carbon fiber reinforced polyamide (PA-CF) is among the most promising composite filaments due to its excellent properties. While the mechanical characteristics of this specific composite have been widely studied, the corresponding performance of lightweight cellular structures made of PA-CF is not well known. The second part of this thesis investigated the mechanical performance of a wide range of cellular structures made of PA-CF through compression testing and high-speed imaging. The results show that cellular PA-CF structures provide a great combination of high strength and lightweight.
The findings of the thesis show that FFF-produced composites offer great potential for load-bearing applications in a wide range of industries. Further optimization of the polymer-polymer interfaces will enable the reliable application of multi-material printing in load-bearing applications. The additional characterization of the PA-CF cellular structures will focus on their impact performance and will further expand the applications of FFF technology towards the design and manufacturing of energy absorbing structures.
... Furthermore, the print speed (S) was less significant in the polymer (Girden, 1992) case study because the nozzle temperature was kept at 210°C, higher than the PLA melting temperature. This observation agrees with the work reported by (Polak et al., 2017), which concluded that print speed is less significant in determining the dimensional accuracy of polymer for the FFF process. No further experiments are needed because the lack-of-fit error is insignificant. ...
Bioprinting, or bio-additive manufacturing, is a critical emerging field for transforming tissue engineering regenerative medicine to produce biological constructs and scaffolds in a layerwise fashion. Geometric accuracy and spatial distribution of scaffold porosity are critical factors associated with the quality of bio-printed tissue scaffolds. Determining optimal process parameters for tissue scaffold microextrusion 3D printing by traditional trial-and-error approaches is costly, labor-intensive, and time-consuming. In addition, effective in-process sensing techniques are needed to observe internal multilayer scaffold structures, such as porosity. Therefore, an in-process sensing platform based on integrated light scanning and microscopy was proposed to acquire in-process layer information during the fabrication of polymeric and hydrogel scaffolds. This work implements a customized sensing platform consisting of a 3D scanner and digital microscope for in-process quality monitoring of tissue scaffold biofabrication that provides in situ characterization of each printed layer’s quality conditions (e.g., porosity). The proposed sensor-based in-process quality monitoring system can accurately capture layerwise porosity quality. Design of experiments (DoE) experimental analysis yielded a set of optimal process parameters that significantly improved the geometric accuracy and compressive modulus of thermoplastic- and hydrogel-based tissue scaffolds. The developed sensing system coupled with the DoE approach enables effective process parameter optimization to fabricate porous 3D-printed tissue scaffolds. It can significantly improve the quality and reproducibility of research associated with porous 3D-printed products, such as tissue scaffolds and membranes.
... Finding and setting appropriate process parameters in AM and in other complex manufacturing technologies is often performed by empirical modeling, varying one or more process parameters in a limited range, and observing the effects on the manufactured parts [17][18][19][20][21][22][23]. However, as stated in Section 1 regarding the specific challenge in parameter generation for FDM, varying all relevant parameters results in an unmanageable quantity of trials. ...
Additive manufacturing has revolutionized prototyping and small-scale production in the past years. By creating parts layer by layer, a tool-less production technology is established, which allows for rapid adaption of the manufacturing process and customization of the product. However, the geometric freedom of the technologies comes with a large number of process parameters, especially in Fused Deposition Modeling (FDM), all of which influence the resulting part’s properties. Since those parameters show interdependencies and non-linearities, choosing a suitable set to create the desired part properties is not trivial. This study demonstrates the use of Invertible Neural Networks (INN) for generating process parameters objectively. By specifying the desired part in the categories of mechanical properties, optical properties and manufacturing time, the demonstrated INN generates process parameters capable of closely replicating the desired part. Validation trials prove the precision of the solution with measured properties achieving the desired properties to up to 99.96% and a mean accuracy of 85.34%.
This study involves the experimental evaluation of the tensile strength of Polylactic Acid (PLA) materials processed using the Fused Deposition Modeling (FDM) additive manufacturing method. PLA is a frequently preferred material in 3D printing technologies due to its advantages such as biocompatibility, biodegradability, and excellent printing properties. The aim of this study is to analyze the effects of printing parameters and material properties on the tensile strength of PLA and to provide potential strategies for optimizing the durability and efficiency of PLA materials produced using 3D printing technology. The methodology of the study focuses on examining four carefully selected key parameters: fan speed, infill pattern, infill density, and part orientation. A total of 81 samples were produced and experimentally tested with different combinations of these parameters. The purpose of these comprehensive tests is to analyze in detail the effects of these parameters on the tensile strength of PLA materials and to determine the parameter combinations that provide the best performance. The experimental results obtained demonstrate that printing parameters and material properties have a significant impact on the tensile strength of PLA. Factors such as fan speed, infill pattern, infill density, and part orientation have been identified as critical elements determining the overall durability of the material. For example, when the fan speed is low, the material spends more time during the cooling process, resulting in an increase in tensile strength. Infill pattern and infill density affect the internal structure of the material and are therefore important factors determining tensile strength. Part orientation determines the direction in which the material stretches during printing and is another important parameter affecting tensile strength. This study provides valuable information for optimizing the tensile strength of PLA materials produced using 3D printing technology. With the proper adjustment of parameters such as fan speed, infill pattern, infill density, and part orientation, it is possible to obtain PLA products with the desired mechanical properties. This information serves as an important guide for researchers, engineers, and designers in various fields, from industrial production to prototype development, who use 3D printing technology. In conclusion, this study emphasizes the need for careful control of parameters that affect the tensile strength of PLA materials. The durability of PLA can be optimized with the appropriate combinations of factors such as fan speed, infill pattern, infill density, and part orientation. This information guides researchers and industry professionals in making 3D printed PLA materials more reliable and effective.
3D printing is a rapidly developing technology in the medical world that has been used for pre-operative planning, prosthetic manufacturing, and training for medical education. This 3D printing is needed for medical education to make it easier for students to study anatomical structures. The advantages of 3D printing provide more detail and tactile representation of anatomical aspects of organs to address the problems of online learning and cadaveric limitations. This research aimed to develop the manufacture of 3D printed models of the human heart organ to improve understanding in learning for medical students. Making a 3D printed model of a heart organ is divisible into six parts: the aorta, right ventricle, left atrium, left ventricle, right atrium, and pulmonary artery. The 3D printing model creation procedure consisted of several steps: image acquisition, image post-processing, and 3D printing. This research used Computed Tomography Scanning (CT-Scan) images of the normal heart in Digital Imaging in Medicine (DICOM) format from Saiful Anwar Hospital, Malang. The segmentation uses the grow from seed technique with 3D Slicer software and is saved in STL format. The accuracy of the 3D printing was carried out by measuring dimensions and volume. Measurements are required to ensure the accuracy of 3D printing so that the resulting organs match the initial image data and can be used as learning media in anatomical structures by medical students.
Fused deposition modeling is one of the most widely used 3-D printing
technologies, among other additive manufacturing processes, because it is
easy to use, can produce parts faster, and the cost of the finished part is
low. Printing processes and finished parts are often studied and
characterized using different techniques to collect mechanical, numerical,
thermal and dimensional data, with the aim of improving and optimizing the
result. The first part of this research is based on the observation of
temperature changes with a thermal imaging camera during the fused
deposition modeling printing process and during the cooling process after
printing. Specimens of polylactic acid and polylactic acid-X improved with
second-phase particles were prepared to compare the thermal and dimensional
properties of the two materials. The obtained results determined the
characteristic temperature behavior of the materials. In the second part of
the research, a 3-D optical scanner was used to verify the stability and
accuracy of the printed specimens over time. The proposed measurement period
showed that stabilization of the parameters takes place, and further
follow-up should be performed thereafter.
The paper presents experimental results the influence of location and direction of the models on the virtual platform on their selected mechanical properties such as Young's modulus and stress relaxation during uniaxial compression tests. Cylindrical samples were manufactured using the Dimension 1200es machine realizing the fused deposition modeling technology (FDM).. The samples were located on the machine platform at different angles to the printing direction. The material used for the construction of samples was ABS P430. Tests relaxation were made in accordance with ISO 3384: 2002 standard. Tests were performed using the testing machine Inspect Mini.
This study, we detail the constructional selection of a machine, which operates with FDM technology. We outline the milestones of the reconstruction of the printer, the restoration of the technical documentations (Reverse Engineering), and then the calibrations and the measurement results. Based on what we have learned from the construction, we started to design our own FDM printer, which is a compact, user demand-driven device.
Fused Deposition Modelling (FDM) has become extensively used for low-cost printers. Normally, commercial manufacturers of printers only provide information on layer thickness, but no information is given as to dimensional accuracy, and the surface characteristics obtained in manufactured components. The aim of this study was to determine the dimensional accuracy, flatness, and surface texture obtained in FDM rapid prototype with ABS-plus as the model material. In the experimental test, two densities (low, solid) and two layer thicknesses (0.178mm, 0.254mm) were used. The best dimensional behaviour was obtained with the configuration of maximum layer thickness (0.254mm) and solid density (100%) with a maximum deviation length of 〛 36μm. The best finish surface and minimum flatness error were obtained with less layer thickness (0.178mm) and solid density (100%). This study has established the optimum configurations for the manufacture of components with FDM 3D printing and ABS-plus.
This book presents a selection of papers on advanced technologies for 3D printing and additive manufacturing, and demonstrates how these technologies have changed the face of direct, digital technologies for the rapid production of models, prototypes and patterns. Because of their wide range of applications, 3D printing and additive manufacturing technologies have sparked a powerful new industrial revolution in the field of manufacturing. The evolution of 3D printing and additive manufacturing technologies has changed design, engineering and manufacturing processes across such diverse industries as consumer products, aerospace, medical devices and automotive engineering. This book will help designers, R&D personnel, and practicing engineers grasp the latest developments in the field of 3D Printing and Additive Manufacturing. © Springer Nature Singapore Pte Ltd. 2019. All Rights Reserved.
Fused deposition modelling (FDM) is one of the most widely used cost-effective additive manufacturing (AM) technique for modelling and prototyping of functional/non-functional parts subjected to different industrial applications. However, this technique still possesses substantial problems in-terms of poor surface finish and dimensional accuracy of the prototypes. In the present research work, an effort has been made to improve the surface finish of FDM based benchmarks through chemical (acetone) exposure by using vapor smoothing station (VSS). Experimental analysis has been carried out by using design of experiments (DOE) technique in-order to find out the effect of input factors on surface finish of the benchmarks. The results of the present study highlights the capability of the VSS for improving the surface finish of the FDM based parts to nano-level with negligible dimensional deviations.
3D Printing and Additive Manufacturing (AM) has revolutionised how prototypes are made and small batch manufacturing carried out. With additive manufacturing, the strategies used to produce a part change a number of important considerations and limitations previously faced by tool designers and engineers. This textbook is the fourth edition of Rapid Prototyping: Principles and Applications. It covers the key AM processes, the available models and specifications, and their principles, materials, advantages and disadvantages. Examples of application areas in design, planning, manufacturing, biomedical engineering, entertainment, weaponry, art and architecture are also given. The book includes several related problems for the reader to test his or her understanding of the topics. This edition comes with a companion media pack that presents animated illustrations of the working principles of today’s key AM processes. © 2015 by World Scientific Publishing Co. Pte. Ltd. All rights reserved.
In the recent years, the whole world is facing a serious problem in handling nylon-6 wastes of various societies like: fibres/textile, household, carpets, tires, military supplies, etc. Ordinary recycling process of such wastes is costlier process and also omits its major mechanical properties. In the present research work, nylon-6 waste (collected from local plastic based industry) has been recycled, through extrusion process, in the form of fused deposition modelling (FDM) feedstock filament. This alternatively developed FDM filament has been successfully used to fabricate sacrificial patterns for investment casting process (ICP). The process was started with investigating the melt flow index (MFI) of collected nylon-6 waste which was matched with the commercial FDM filament through reinforcement. Finally, single screw extruder of has been used for the development of FDM filament proportion with a mixture of 60% nylon-6, 30% Al and 30% Al2O3 (by wt.). The resulting FDM patterns have been used in ICP for development of aluminum matrix composite (AMC). Taguchi L9 was used to investigate the affect of process parameters (volume of pattern, density of pattern and number of IC coatings) on dimensional accuracy of AMC developed. Apart from suggesting an alternative method for management and recycling of nylon-6 waste, the present research work also described a new approach for the development of AMC with tailor made properties.
2015-Additive manufacturing-General principles-Terminology'. International Organization for Standardization
- Iso Astm
ISO/ASTM 52900:2015-Additive manufacturing-General principles-Terminology'. International Organization
for Standardization, Dec-2015.
Siemens NX 11 User's Guide
- Plm Siemens
- A G Siemens
Siemens PLM. (2016) Siemens NX 11 User's Guide. Siemens AG..
Introduction and Basic Principles in Additive Manufacturing Technologies
- I Gibson
- D Rosen
- B Stucker
I. Gibson, D. Rosen, and B. Stucker. (2015). Introduction and Basic Principles in Additive Manufacturing
Technologies, Springer New York, pp. 1-18, New York.