FDM Technology Research Articles

The effects of design parameters on the elastic properties of PLA-Graphite composites fabricated by 3D printing

Abstract. Recently, in 3D printing, consumables such as polymers, metals, and ceramics are being replaced with composites, which makes it possible to enhance the mechanical and other important properties of products.
 The purpose of this study is to investigate the effects that the orientation and thickness of the layers of printed samples made of composite monofilament based on PLA+ with a 5% content of layered graphite, and other such parameters, have on the elastic properties of the printed samples. The samples, developed in accordance with the DSTU EN ISO 527-2: 2018 standard, were printed using the FDM technology with three different orientation angles (0o, 45o, 90o) and three layer thicknesses (0,1 mm, 0,2 mm, 0,3 mm) for each angle. Tensile tests were performed using the complete factorial experiment design (consisting of two factors at three levels, with nine tests in total). Based on the results of these tests, a regression model was developed to describe the relationship between the (effective) modulus of elasticity and the selected design parameters.

Experimental Investigation on Influence of Infill Density on Tensile Mechanical Properties of Different FDM 3D Printed Materials

One of the advantages of FDM technology is the production of product materials with infill structure. In order to make the most of this advantage, the behaviour of FDM printed material with infill structure under different loads has to be analyzed and understood. Therefore, the goal of this experimental research is to analyze influence of infill density (100%, 80%, 60% and 20%) on tensile mechanical properties (tensile strength and elastic modulus) of PLA antibacterial nanocomposite, tough PLA and ABS-X 3D printed materials.

Study of the tensile strength of a polymer composite material based on ABS-plastic and impregnated in epoxy resin with different types of hardener

AnnotationThis article examines the study of strength properties of polymer composite material, based on 3D-printed frame produced by FDM technology. The printing material is ABS plastic (acrylonitrile butadiene styrene). After the printing samples frames were soaked in pure epoxy resin with various hardeners. Subsequent curing went in two modes. After that, tensile tests were performed. The strength of impregnated, non-impregnated (clean frame) samples and samples made of pure resin was compared. Tests have shown that the strength of impregnated samples exceeds the strength of non-impregnated ones, but obtained strength value of impregnated samples were far from the expected theoretical values. It was found that low strength is associated with poor quality of the impregnation.

The Design Research Analysis of 3D Printer Based on FDM

With the great breakthrough of 3D printing technology, it has been widely and deeply applied in the industrial field. 3D printing technology and the Internet of things jointly build an organic intelligent industrial system. The 3D printer using FDM technology can significantly improve the printing accuracy, reduce the processing difficulty of complex parts and make the maintenance and operation process of 3D printer simpler. Based on this, this paper first analyzes the technical principle and characteristics of 3D printer, and then studies the classification and technical classification analysis of 3D printer; finally, it gives the design of 3D printer based on FDM.

Multi-axis Fused Deposition Modeling using parallel manipulator integrated with a Cartesian 3D printer

An attempt was made to build a simple and low-cost device capable of positioning 3D prints for the process of additive manufacturing to conveniently allow the desired extend of the existing 3D printing capabilities. 3D printing with the use of increased number of axes, as compared to the standard approach, can eliminate such disadvantages of FDM technology as orthotropy of prints, surface roughness, and the consumption of both time and material devoted to make support structures. A CAD design of a parallel manipulator, used as a positioning table (platform), was developed, which was used for numerical simulations, and then a physical manipulator was made. The table was tested independently, i.e., as a stand-alone device, and, next, in cooperation with a 3D printer which allowed to obtain non-planar prints. The obtained results allowed for both the identification of problems related to multi-axis 3D FDM printing and an attempt to formulate concepts enabling to overcome them via adequate design and control modifications. The raised conclusions will be used to further development and more comprehensive understanding the phenomena that are present during the investigated manufacturing process.

Optimization of Temperature Regimes of the Hotend for Devices of Additive Manufacturing

In this work, the authors tried to solve a typical problem of inexpensive 3D printers using FDM technology: material clogging of the hotend. To cope with the problem, it is necessary to solve the problem of optimization the temperature regimes of the hotend. For this, the temperature fields of the heating device were simulated taking into account the physical properties of the printing materials. Modeling was carried out using the ANSYS software package, the verification of theoretical calculations was carried out in a full-scale experiment. The data obtained was used to upgrade the 3D printer hotend.

Determining the Optimal Printing Conditions for the Production of a Fertigation Pump Prototype with FDM Technology

The article presents the optimization of a production process with the help of FDM technology of a fertigation pump prototype that does not require other energy source than that given by the flow and pressure of water for irrigation. In the research presented in this article specimens of PETG material are tested in terms of mechanical properties by using a tensile test equipment. The results of these tests are used to dimension and simulate with finite element the component elements of the pump.

Advanced Configuration Parameters of Post Processor Influencing Tensile Testing PLA and Add-Mixtures in Polymer Matrix in the Process of FDM Technology

The present paper focuses on the configuration possibilities of post -processor influencing mechanical properties of a given test sample produced by the FDM printer from different materials. The research consists of assessing the composite material configurations through a static tensile test conducted on 80 samples produced. The samples were produced based on ISO 527-2 standard, type 1A, with a horizontal position and a layer height of 0.2 mm. The individual samples consisted of four basic groups of materials—the pure Polylactic acid (PLA) plastic (reference sample), and three composite samples with admixtures—PLA matrix with a copper admixture, PLA matrix with an iron admixture, and PLA matrix with a steel admixture. The static tensile test was conducted at a test speed of 5 mm/min. During the research, reference samples (pure PLA) were assessed in five orientations. Samples made of the PLA composite materials with admixtures were manufactured, tested, and evaluated only in the 0° orientation. The paper concludes by comparing the results of measurement with the original material, free from additives, and with the researched influence of the orientation of the prints on the resulting mechanical properties of shear samples and their surface structure. In the conducted experiments, the lowest tensile strength has been demonstrated in test samples the orbital transitions and the upper surface layers of which were parallel to the infill.

The Possibility to Recreate the Shapes of Objects on the Basis of Printer Vibration in the Additive Printing Process

Information protection is an important safety issue in many human activity fields. Technological advances and related ubiquitous computerization bring new challenges in this area. In particular, the problem concerns the protection of devices against non-invasive acquisition processed information in ICT systems. It is known that, e.g., VGA, DVI/HDMI interfaces or laser printer formatter systems that process visual signals are the effective sources of compromising electromagnetic emanations. The emission safety of the more and more commonly used 3D printers is less known. In many cases, the disclosure of information about printed objects might constitute an infringement of the state/industrial/commercial secret, copyright, patent protection, etc. In order to analyze the existing threat, a selected printer using FDM technology was tested. During the tests, simple objects were printed to identify the operation of the stepper motor and the movements of the printer head and the printer platform, which are sources of emissions in the secondary channels. The analyses performed focused on finding the correlation between the recorded vibration signals and the printer head movements when an object was printed. It was shown that the analysis of the registered sensitive signal runtimes and their spectrograms allowed to recreate the printed object shape. Three simple objects (a trihedron, a tube and a tetrahedron) were selected for testing because they include elements that allow the four major movements of the printer head to be easily recognized: along the X axis, along the Y axis, along an arc and diagonally (between the X and Y axes). The paper presents the test results and their analyses.

Development of Personal Protective Respirator Based on Additive Manufacturing Technologies in Fighting Against Pandemic

Flexible manufacturing systems have been widely used especially in the field of medicine to develop personal protective types of equipment such as ventilator components or sample collection apparatuses except the face visors and masks/respirators during the fight against the pandemic. In this study, an N95 derivative respirator was designed based on the FDM technology and then compared with similar known mask models in literature in terms of manufacturing costs and functionality. Optimization was carried out on printing parameters to improve the speed of manufacturing. Finally, all components of the mask were assembled and prepared to be used for medical needs during the pandemic. The cost of the mask and filter components were reduced to 7 ₺ for 2 hours and 32 minutes for each mask. Moreover, the durability of each mask was increased three times more than known protective types of equipment to offer longer usage without any fractures caused by daily activities and to have improved airtightness. Besides, the mask was designed to have multi-layered filters with the ability of replaceable membranes according to the epidemic agent, and the sterilization procedures were explained. Thus, a more economical and healthier protective equipment was created compared to the known respirators in the literature.

A New Approach to Optimize the Relative Clearance for Cylindrical Joints Manufactured by FDM 3D Printing Using a Hybrid Genetic Algorithm Artificial Neural Network and Rational Function

Nowadays, FDM technology permits obtaining functional prototypes or even end parts. The process parameters, such as layer thickness, building orientation, fill density, type of support, etc., have great influence on the quality, functionality and behavior of the obtained parts during their lifetime. In this paper, we present a study concerning the possibilities of obtaining certain values for clearance in revolute joints of non-assembly mechanisms manufactured by FDM 3D Printing. To ensure the functioning of the assembly, one must know the relationship between the imposed and measured clearances by taking into account the significant input data. One way is to use the automat learning method with an artificial neuronal network (ANN). The data necessary for the training, testing, and validation of ANN were experimentally obtained, using a complete L 27 Taguchi experimental plan. A total of 27 samples were printed with different values of the following parameters: the infill density, the imposed clearance between the shaft and the hole, and the layer thickness. ANN architecture corresponds to the Hecht–Kolmogorov theorem. Genetic algorithms (GA) were used for the optimization of the output. The Neural Network Toolbox from MATLAB was used for training the network and a hybrid tool genetic algorithm artificial neural network (GA-ANN) was used to minimize the value of the absolute relative clearance (arc). The minimum value of the absolute relative clearance established by GA-ANN was 0.0385788. This value was validated experimentally, with a relative difference of 4%. We also introduced a rational function to approximate the correlation between the input and output parameters. This function fulfills some frontier conditions resulted from practice. In addition, the function may be used to establish the designed clearance in order to obtain an imposed one.

Quality of Surface Texture and Mechanical Properties of PLA and PA-Based Material Reinforced with Carbon Fibers Manufactured by FDM and CFF 3D Printing Technologies.

The paper presents the results of mechanical tests of models manufactured with two 3D printing technologies, FDM and CFF. Both technologies use PLA or PA-based materials reinforced with carbon fibers. The work includes both uniaxial tensile tests of the tested materials and metrological measurements of surfaces produced with two 3D printing technologies. The test results showed a significant influence of the type of technology on the strength of the models built and on the quality of the technological surface layer. After the analysis of the parameters of the primary profile, roughness and waviness, it can be clearly stated that the quality of the technological surface layer is much better for the models made with the CFF technology compared to the FDM technology. Furthermore, the tensile strength of the models manufactured of carbon fiber-enriched material is much higher for samples made with CFF technology compared to FDM.

Експериментальний аналіз механічних характеристик деталей ракет-носіїв, виготовлених за допомогою FDM адитивних технологій

Additive manufacturing is very promising for aerospace engineering and aircraft construction. Using these technologies, light structures with preset strength properties can be made. For lack of tables of the mechanical properties of materials made by additive technologies, any calculation must be accompanied by the experimental determination of their mechanical properties. This paper presents an experimental approach to the determination of the mechanical characteristics of parts printed by FDM technologies. Parts manufactured from polymers by FDM technologies are shown to be orthotropic. Therefore, their elastic properties are described by nine constants: three Young’s moduli, three shear moduli, and three Poisson ratios. A cube is printed for the experimental determination of these constants. Six specimens are cut out from the cube. Three specimens are cut parallel to the cube edges, and the other three are cut at an angle of 45° to them. Each such specimen is manufactured in five pieces. This makes it possible to average the tensile stress–strain diagrams obtained for all the components of the stress tensor. The mechanical properties of the material are determined from these diagrams. The three Young’s moduli and the three Poisson ratios are determined from the three specimen types parallel to the cube edges. The three shear moduli are determined from the specimens cut at an angle of 45° to the cube edges. To determine these constants, tensile stress–strain diagrams are obtained experimentally. A technology is presented for manufacturing specimens on a Stratasys FORTUS 900 MC 3D printer. The mechanical properties of two polymer materials (ULTEM 9085 and PLA) are determined and compared. PLA has higher Young’s moduli and shear moduli and lower Poisson ratios than ULTEM 9085.

Comparative Analysis of Polypropylene Component manufactured by FDM and Injection Molding Technology

Comparative Analysis of Polypropylene Component manufactured by FDM and Injection Molding Technology

Determining the parameters for a 3D-printing process using the fused deposition modeling in order to manufacture an article with the required structural parameters

The mass application of FDM technology is slowed down due to the difficulty of selecting 3D printing parameters in order to manufacture an article with the required characteristics. This paper reports a study into the impact of 3D printing parameters (temperature, print speed, layer height) on mechanical parameters (strength, elasticity module), as well as on the accuracy of printing and roughness of the surface of a specimen based on thermoplastic (PLA plastic). Several batches of specimens were fabricated for this study in accordance with ASTM D638 and ASTM D695, which were tested for tension, geometric accuracy, and roughness. Based on the experimental data, regression analysis was carried out and the functional dependences of the strength, elasticity module, printing precision, roughness of a surface on 3D printing parameters (temperature, speed, thickness of the layer) were constructed. In addition, the derived mathematical model underlying a method of non-linear programming has established such printing parameters that could provide for the required properties of a structure. The analytical dependences reported in the current work demonstrate a high enough determination factor in the examined range of parameters. Using functional dependences during the design phase makes it possible to assess the feasibility of its manufacture with the required properties, reduce the time to work out the process of printing it, and give recommendations on the technological parameters of 3D printing. The recommendations from this study could be used to make PLA-plastic articles for various purposes with the required properties

Tuning the structural and functional properties of HAVOH-based composites via ionic liquid tailoring of MWCNTs distribution

The structural and functional properties of polymer composite materials strictly depend on the spatial distribution of fillers, such as multiwalled carbon nanotubes (MWCNTs), inside the matrix. Herein, novel composites have been obtained by embedding MWCNTs into a modified polyvinyl alcohol (HAVOH) matrix, using the ionic liquid (IL) 1-Benzyl-3-methylimidazolium chloride (BenzImCl) as compatibilizer. The composites were prepared by solvent-wrapping carbon nanotubes onto HAVOH powders, followed by the melt-compounding approach to produce pellets for Fused Deposition Modelling technology (FDM). The efficacy of both the process and the IL on tailoring the spatial distribution of the MWCNTs into the HAVOH matrix is thoroughly studied and correlated with the electrical conductivity of the resulting composites. The sample printed by FDM, containing 6 wt % of MWCNTs and 0.6 wt% of IL exhibited a percolating morphology and led to an electrical conductivity (σ) value of 1.2*10−2 S/m. Moreover, after annealing at 220 °C for 2 h the σ value increased up to 7.9*10−1 S/m. The thermal treatment in presence of the MWCNTs also induces the formation of crosslinked HAVOH molecules changing the composites from easily soluble to completely water insoluble materials. This revealed the potential of HAVOH-based composites as raw material for FDM technology to realize post-printing cross-linkable materials.

Effect of molecular weight on mechanical properties and microstructure of 3D printed poly(ether ether ketone)

AbstractFused deposition modeling (FDM) has been successfully applied to the manufacturing of poly(ether ether ketone) (PEEK) special engineering plastics. However, due to the unavoidable defects caused by FDM technology and the high melt viscosity of PEEK, 3D printed PEEK parts have poor mechanical properties. In this study, the mechanical properties and microstructure of PEEK printed with different nozzle temperatures and having various molecular weights were researched in detail. The results showed that PEEK‐033G with medium molecular weight had good fluidity. With a nozzle temperature of 410 °C and using a high‐temperature chamber 3D printing system, the defects of 3D printed PEEK‐033G were reduced significantly, and the tensile strength and flexural strength could reach 96 and 115 MPa, which is close to the performance obtained using injection molding. In addition, the tensile strength in the Z‐axis direction was applied to characterize the interlayer bond strength. With a decrease of the viscosity of PEEK, an increase of interlayer bond strength ensued. It is expected that these findings could provide more insight for 3D printing of PEEK. © 2020 Society of Chemical Industry

АЛГОРИТМ ДЕЛЕНИЯ ОБЪЕМНОЙ МОДЕЛИ НА КРИВОЛИНЕЙНЫЕ СЛОИ ДЛЯ 3D–ПЕЧАТИ

The article is devoted to the development of the theoretical foundations of the additive shaping of products using the FDM technology. The analysis is carried out by research in this area. It was revealed that the formation of products using the additive FDM technology has significant drawbacks. They are primarily associated with the anisotropy of the physical and mechanical properties of products in the longitudinal and transverse directions. This affects the level of performance of these products. One of the directions for solving the problem of the formation of anisotropy, as well as its control, is the formation of the structure of the product by spatial curvilinear layers. Algorithms for dividing a digital model into curvilinear spatial layers for 3–D printing are proposed here, namely, the layers are divided into cylindrical, conical, spherical. This will provide the formation of products using the FDM technology with spatial curved layers. The results represent the implementation of the developed algorithms for dividing a digital model into spatial curved layers for 3D printing. The application of the proposed algorithms will improve the physicochemical properties of products by forming spatial curvilinear layers.

Manufacturing of 3 D Shrouded Impeller of a Centrifugal Compressor on 3D-Printing machine using FDM Technology

Blades of impellers are intricate and are having complex profiles which are difficult to be manufactured by convectional milling processes. To produce such multifaceted precise dimensional functional components, expertise combined with new technology machining such as 5-Axis CNC machining is required which is costly and tedious task. The impellers components have maximum diameters of 200mm and thickness of blades are less than 1.5mm. A rapid manufacturing technique aids in manufacture of blade profiles which are robust in design and prototypes can be easily made for testing and analysis this aid in design validation. In particular, the investigation was focused on shrouded and unshrouded 3D impeller of centrifugal compressors. The present paper describes about the basic functioning of FDM based 3D printer while printing open and shrouded impeller and various steps involved in it and finally advantages and disadvantages associated with 3D printing technology.

Thickness effect on the fracture behavior of structural components fabricated via Fused Deposition Modeling

In general, the mechanical properties of components produced with additive manufacturing (AM) are dependent on both the geometry and thickness of fabricated parts. Any change will influence the underlying fabrication process and inherent characteristics. Therefore, it is vital to understand the dependency of mechanical behavior of produced components to improve the designability and applicability. In this study, the thickness effect on fracture behavior of PLA specimens fabricated via FDM technology has been investigated. Overall, 15 double edged notched tension (DENT) specimens were produced layer by layer with three different thicknesses of 1mm, 3mm and 5mm. Fracture properties such as fracture load and critical stress intensity factor (SIF) were determined and analyzed from the experimental fracture tests and numerical simulations. 2D digital image correlation (DIC) analyses were performed to evaluate the full-field displacement and strain distributions around crack tips of the specimens. The experimental results indicated that there is a strong correlation between the building thickness and critical SIF. Specimens with larger building thickness experience lower critical SIF due to the fact that thicker specimens have a smaller plastic deformation zone which can lead to both smaller energy dissipation and smaller critical SIF. Furthermore, thinner specimens have higher possibility of developing fracture trajectories along the raster angles.