Basic Research for Additive Manufacturing of Rubber

The dissemination and use of additive processes are growing rapidly. Nevertheless, for the material class of elastomers made of vulcanizable rubber, there is still no technical solution for producing them using 3D printing. Therefore, this paper deals with the basic investigations to develop an approach for rubber printing. For this purpose, a fused deposition modeling (FDM) 3D printer is modified with a screw extruder. Tests are carried out to identify the optimal printing parameters. Afterwards, test prints are performed for the deposition of rubber strands on top of each other and for the fabrication of simple two-dimensional geometries. The material behavior during printing, the printing quality as well as occurrences of deviations in the geometries are evaluated. The results show that the realization of 3D rubber printing is possible. However, there is still a need for research to stabilize the layers during the printing process. Additionally, further studies are necessary to determine the optimum parameters for traverse speed and material discharge, especially on contours.

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Process Parameter Optimization in Fused Deposition Modeling (FDM) Using Response Surface Methodology (RSM)

10.21203/rs.3.rs-122421/v1 ◽

2020 ◽

Author(s):

Muhammad Salman Mustafa ◽

Muhammad Qasim Zafar ◽

Muhammad Arslan Muneer ◽

Muhammad Arif ◽

Farrukh Arsalan Siddiqui ◽

...

Keyword(s):

Mechanical Properties ◽

Response Surface Methodology ◽

Impact Strength ◽

Response Surface ◽

Layer Thickness ◽

Fused Deposition Modeling ◽

Experimental Results ◽

Fused Deposition ◽

Deposition Modeling ◽

Printing Parameters

Abstract Fused Deposition Modeling (FDM) is a widely adopted additive manufacturing process to produce complex 3D structures and it is typically used in the fabrication of biodegradable materials e.g. PLA/PHA for biomedical applications. However, FDM as a fabrication process for such material needs to be optimized to enhance mechanical properties. In this study, dogbone and notched samples are printed with the FDM process to determine optimum values of printing parameters for superior mechanical properties. The effect of layer thickness, infill density, and print bed temperature on mechanical properties is investigated by applying response surface methodology (RSM). Optimum printing parameters are identified for tensile and impact strength and an empirical relation has been formulated with response surface methodology (RSM). Furthermore, the analysis of variance (ANOVA) was performed on the experimental results to determine the influence of the process parameters and their interactions. ANOVA results demonstrate that 44.7% infill density, 0.44 mm layer thickness, and 20C° printing temperatures are the optimum values of printing parameters owing to improved tensile and impact strength respectively. The experimental results were found in strong agreement with the predicted theoretical results.

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Fully resolved numerical simulations of fused deposition modeling. Part II – solidification, residual stresses and modeling of the nozzle

Rapid Prototyping Journal ◽

10.1108/rpj-11-2017-0233 ◽

2018 ◽

Vol 24 (6) ◽

pp. 973-987 ◽

Cited By ~ 19

Author(s):

Huanxiong Xia ◽

Jiacai Lu ◽

Gretar Tryggvason

Keyword(s):

Residual Stresses ◽

Numerical Simulations ◽

Fused Deposition Modeling ◽

Fixed Bed ◽

Ground Truth ◽

Deposition Process ◽

Material Behavior ◽

Content Type ◽

Fused Deposition ◽

Deposition Modeling

Purpose The purpose of this paper is to continue to describe the development of a comprehensive methodology for fully resolved numerical simulations of fused deposition modeling. Design/methodology/approach A front-tracking/finite volume method introduced in Part I to simulate the heat transfer and fluid dynamics of the deposition of a polymer filament on a fixed bed is extended by adding an improved model for the injection nozzle, including the shrinkage of the polymer as it cools down, and accounting for stresses in the solid. Findings The accuracy and convergence properties of the new method are tested by grid refinement, and the method is shown to produce convergent solutions for the shape of the filament, the temperature distribution, the shrinkage and the solid stresses. Research limitations/implications The method presented in the paper focuses on modeling the fluid flow, the cooling and solidification and volume changes and residual stresses, using a relatively simple viscoelastic constitutive model. More complex material models, depending, for example, on the evolution of the conformation tensor, are not included. Practical implications The ability to carry out fully resolved numerical simulations of the fused deposition process is expected to be critical for the validation of mathematical models for the material behavior, to help explore new deposition strategies and to provide the “ground truth” for the development of reduced-order models. Originality/value The paper completes describing the development of the first numerical method for fully resolved simulation of fused filament modeling.

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Properties and applications of electrically conductive thermoplastics for additive manufacturing of sensors

tm - Technisches Messen ◽

10.1515/teme-2016-0057 ◽

2017 ◽

Vol 84 (9) ◽

Cited By ~ 6

Author(s):

Benedikt Hampel ◽

Samuel Monshausen ◽

Meinhard Schilling

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Electrical Conductance ◽

Electrically Conductive ◽

Fused Deposition ◽

Printing Technique ◽

Deposition Modeling ◽

3D Printed ◽

3D Printing Technique ◽

Printing Parameters

AbstractIn consequence of the growing diversity of materials in the fused deposition modeling 3D printing technique, electrically conductive materials are commercially available. In this work two filaments based on thermoplastics filled with carbon or metal nanoparticles are analyzed in terms of their electrical conductance. The printing parameters to process the materials with the 3D printer are optimized with the design of experiments (DoE) method. A model to calculate the resistance of such 3D printed structures is presented and a demonstrator as a proof of concept was 3D printed based on these results. In addition, 3D printing of capacitors is investigated.

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

Eastern-European Journal of Enterprise Technologies ◽

10.15587/1729-4061.2021.227075 ◽

2021 ◽

Vol 2 (1 (110)) ◽

pp. 70-80

Author(s):

Oleksii Vambol ◽

Andrii Kondratiev ◽

Svitlana Purhina ◽

Maryna Shevtsova

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Structural Parameters ◽

Technological Parameters ◽

Non Linear Programming ◽

Fused Deposition ◽

Elasticity Module ◽

Deposition Modeling ◽

The Impact ◽

Printing 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

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Experimental investigation using vibration testing method to optimize feed parameters of color mixing nozzle for fused deposition modeling color 3D printer

Advances in Mechanical Engineering ◽

10.1177/1687814019896196 ◽

2019 ◽

Vol 11 (12) ◽

pp. 168781401989619 ◽

Cited By ~ 1

Author(s):

Zhiyong Li ◽

Dawei Zhang ◽

Liangchen Shao ◽

Shanling Han

Keyword(s):

Fused Deposition Modeling ◽

Vertical Vibration ◽

Feed Speed ◽

3D Printer ◽

Feed Material ◽

Fused Deposition ◽

Printing Quality ◽

Deposition Modeling ◽

Color Mixing

To improve the blockage and printing quality of the color mixing nozzle of fused deposition modeling color 3D printer, the feed parameters of fused deposition modeling color 3D printer were studied by vibration test. The acceleration sensor was fixed up the color mixing nozzle to analyze the vertical vibration of the nozzle. The vibration test of different feed speed, torque, and material were performed under the actual printing condition. Vertical vibration of the nozzle was characterized by an acceleration sensor. The comparative analysis of the actual testing results indicates that the optimum feed parameters are feed torque of triple torque extruder, feed speed of 20 mm/s, and feed material of ABS. Further analysis shows that higher feed torque can be used to improve the printing quality of the color mixing nozzle. The appropriate feed speed of the color 3D printer can not only reduce the accumulation of wire material at a lower speed but also reduce the blockage caused by too-high feed speed. It is proposed that the feed material with smaller flow behavior index and no phase transition in the melting process shows smaller vibration acceleration amplitude.

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Effect of FDM Process on Adhesive Strength of Polylactic Acid(PLA) Filament

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.667.181 ◽

2015 ◽

Vol 667 ◽

pp. 181-186 ◽

Cited By ~ 17

Author(s):

Ai Qiong Pan ◽

Zi Fan Huang ◽

Rui Jie Guo ◽

Jun Liu

Keyword(s):

Polylactic Acid ◽

Adhesive Strength ◽

Fused Deposition Modeling ◽

Slice Thickness ◽

Filling Rate ◽

Fused Deposition ◽

Manufacturing Efficiency ◽

Printing Quality ◽

Strength Based ◽

Deposition Modeling

Fused deposition modeling (FDM) is one of the most widely used technologies in rapid prototyping. On the principle of layered manufacturing, the melted polymer filament is extruded and formed. In order to achieve transition from nonfunctional prototypes to functional prototypes of FDMed models, using the RepRap Kossel delta 3D printer and 1.75mm diameter polylactic acid (PLA) filament, it was analyzed that the effects of the nozzle moving rate and slice thickness on adhesive strength based on the existing technology research by orthogonal test. The experiment results indicated that adhesive strength of filament increased both with the nozzle moving rate and with its slice thickness. The latter induced increase more significantly. Finally, comprehensive experiments had been performed to quantitatively study the adhesive strength variation with the filling rate, which provides data reference for setting proper filling rate. Reasonable filling rate setting can not only satisfy the strength requirement without debasement of printing quality, but also reduce filament consumption, improve the manufacturing efficiency and provide important instruction significance for actual printing.

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Stress-limiting test structures for rapid low-cost strength and stiffness assessment

Rapid Prototyping Journal ◽

10.1108/rpj-12-2014-0170 ◽

2015 ◽

Vol 21 (2) ◽

pp. 144-151 ◽

Cited By ~ 2

Author(s):

Andrew Katz ◽

Justin Nussbaum ◽

Craig P Lusk ◽

Nathan B Crane

Keyword(s):

Fused Deposition Modeling ◽

Low Cost ◽

Test Methods ◽

Measurement Sensitivity ◽

Content Type ◽

Fused Deposition ◽

Deposition Modeling ◽

Strength And Stiffness ◽

Accuracy And Repeatability ◽

Printing Parameters

Purpose – The purpose of this paper is to evaluate the use of a simple printed geometry to estimate mechanical properties (elastic modulus, yield strength) with inexpensive test equipment. Design/methodology/approach – Test geometry is presented that enables controlled strains with manual deformation and repeatable measurement of vibrational frequencies. This is tested with multiple fused deposition modeling (FDM) machines to assess measurement accuracy and repeatability. Printing orientation and some printing parameters are varied to assess the measurement sensitivity. Findings – The test methods show good correlation with manufacturer material specifications in the X-Y plane and reported elastic strain limits. It is also sensitive to printing orientation and printing parameters. Research limitations/implications – Further work is needed to assess the sensitivity of the method to particular defects and parameter errors expected in particular applications. Originality/value – This method supports process monitoring in production environments and inexpensive assessments of material properties for hobbyist and do-i- yourself users. While it is tested with FDM, it should be applicable to other additive manufacturing processes.

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Relationship between FDM 3D Printing Parameters Study: Parameter Optimization for Lower Defects

Polymers ◽

10.3390/polym13132190 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2190

Author(s):

Patrich Ferretti ◽

Christian Leon-Cardenas ◽

Gian Maria Santi ◽

Merve Sali ◽

Elisa Ciotti ◽

...

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Research Attention ◽

Fused Deposition ◽

Defect Rate ◽

Study Parameter ◽

Deposition Modeling ◽

Process Viability ◽

Diverse Individual ◽

Printing Parameters

Technology evolution and wide research attention on 3D printing efficiency and processes have given the prompt need to reach an understanding about each technique’s prowess to deliver superior quality levels whilst showing an economical and process viability to become mainstream. Studies in the field have struggled to predict the singularities that arise during most Fused Deposition Modeling (FDM) practices; therefore, diverse individual description of the parameters have been performed, but a relationship study between them has not yet assessed. The proposed study lays the main defects caused by a selection of printing parameters which might vary layer slicing, then influencing the defect rate. Subsequently, the chosen technique for optimization is presented, with evidence of its application viability that suggests that a quality advance would be gathered with such. The results would help in making the FDM process become a reliable process that could also be used for industry manufacturing besides prototyping purposes.

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Effect of Printing Parameters on the Thermal and Mechanical Properties of 3D-Printed PLA and PETG, Using Fused Deposition Modeling

Polymers ◽

10.3390/polym13111758 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1758

Author(s):

Ming-Hsien Hsueh ◽

Chao-Jung Lai ◽

Shi-Hao Wang ◽

Yu-Shan Zeng ◽

Chia-Hsin Hsieh ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Deformation ◽

Fused Deposition Modeling ◽

Complex Geometry ◽

Thermal And Mechanical Properties ◽

Fused Deposition ◽

Internal Structures ◽

Deposition Modeling ◽

3D Printed ◽

Printing Parameters

Fused Deposition Modeling (FDM) can be used to manufacture any complex geometry and internal structures, and it has been widely applied in many industries, such as the biomedical, manufacturing, aerospace, automobile, industrial, and building industries. The purpose of this research is to characterize the polylactic acid (PLA) and polyethylene terephthalate glycol (PETG) materials of FDM under four loading conditions (tension, compression, bending, and thermal deformation), in order to obtain data regarding different printing temperatures and speeds. The results indicated that PLA and PETG materials exhibit an obvious tensile and compression asymmetry. It was observed that the mechanical properties (tension, compression, and bending) of PLA and PETG are increased at higher printing temperatures, and that the effect of speed on PLA and PETG shows different results. In addition, the mechanical properties of PLA are greater than those of PETG, but the thermal deformation is the opposite. The above results will be a great help for researchers who are working with polymers and FDM technology to achieve sustainability.

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Characterization of Material Behavior of the Fused Deposition Modeling Processed Parts

Volume 2: Additive Manufacturing; Materials ◽

10.1115/msec2017-2949 ◽

2017 ◽

Cited By ~ 1

Author(s):

Madhukar Somireddy ◽

Aleksander Czekanski

Keyword(s):

Finite Element ◽

Elastic Moduli ◽

Fused Deposition Modeling ◽

Material Behavior ◽

Constitutive Law ◽

Finite Element Models ◽

Strength Parameters ◽

Fused Deposition ◽

Deposition Modeling

In the present research, one of the additive manufacturing techniques, fused deposition modeling (FDM) fabricated parts are considered for investigation of their material behavior. The FDM process is a layer upon layer deposition of a material to build three dimensional parts and such parts behave as laminated composite structures. Each layer of the part acts as a unidirectional fiber reinforced lamina, which is treated as an orthotropic material. The mesostructure of a part fabricated via fused deposition modeling process is accounted for in the investigation of its mechanical behavior. The finite element (FE) procedure for characterization of a material constitutive law for the FDM processed parts is presented. In the analysis, the mesostructure of the part obtained via FDM process is replicated in the finite element models. Finite element models of tensile specimens are developed with mesostructure that would be obtained from FDM process, then uniaxial tensile test simulations are conducted. The elastic moduli of a lamina are calculated from the linear analysis and the strength parameters are obtained from the nonlinear finite element analysis. The present work provides a FE methodology to find elastic moduli and strength parameters of a FDM processed part by accounting its mesostructure in the analysis.

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