FDM 3D Printing Process - Risks and Environmental Aspects

The application of the 3D printing processes is continuously increasing due to their large number of technical and economic advantages when produce prototypes, but in the mass fabrication as well, especially for metal printing of low dimension products. The process produces pollution as all technological processes. Noise, fume and polymer wastes are the main elements which exit from the process and they are not products. The types and the volumes of those pollution emissions depend on the process parameters. The paper presents the results of FDM process emissions analysis. It was recorded the noise for different stages of the printer functioning. It was measured the volume and the contents of the fume produced during the extrusion of the polymer, for PLA polymer and for ABS polymer filaments. Specific risks were analysed and conclusions were reported. The measurement was done for a random chosen product and the results were compared with the pollutant emissions from traditional technological processes applied to erect the same type of product. It has been concluded that the noise emitted during the FDM printing is about 82-85% of the noise produced when apply milling to create similar shapes and dimensions (it was recorded values for the sound pressure in a large range: 42-68 dB, depending on the working regime). Regarding the fume emission, the intensity of emission was up to 40% higher in the FDM process comparing to the milling process. That was explained as being a direct result of the fluid-viscous state in which the material is put during the printing process. When discuss about the risks, most of the main identified risks in the milling and/or extrusion process were almost inexistent in the FDM printing. Electrical injuries and heat injuries are the main risks to which the operator is exposed. Mechanical injuries are sensitively lower than in the traditional processes, as milling The FDM process is safer and produces lower material wastes. It can be concluded that the FDM printing process has lower impact with the environment and with the operator.

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Influence of Constructive and Technological Parameters at Generated Spiral Parts with DLP 3D Printing Process

Materiale Plastice ◽

10.37358/mp.19.4.5269 ◽

2019 ◽

Vol 56 (4) ◽

pp. 801-811

Author(s):

Mircea Dorin Vasilescu

Keyword(s):

3D Printing ◽

Great Influence ◽

Polymerization Process ◽

Generation Process ◽

Technological Parameters ◽

Printing Process ◽

The Third ◽

Solid Models ◽

Specific Factors ◽

Printing Processes

This work are made for determine the possibility of generating the specific parts of a threaded assembly. If aspects of CAD generating specific elements was analysed over time in several works, the technological aspects of making components by printing processes 3D through optical polymerization process is less studied. Generating the threaded appeared as a necessity for the reconditioning technology or made components of the processing machines. To determine the technological aspects of 3D printing are arranged to achieve specific factors of the technological process, but also from the specific elements of a trapezoidal thread or spiral for translate granular material in supply process are determined experimentally. In the first part analyses the constructive generation process of a spiral element. In the second part are identified the specific aspects that can generation influence on the process of realization by 3D DLP printing of the two studied elements. The third part is affected to printing and determining the dimensions of the analysed components. We will determine the specific value that can influence the process of making them in rapport with printing process. The last part is affected by the conclusions. It can be noticed that both the orientation and the precision of generating solid models have a great influence on the made parts.

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Synergistic application of continuous granulation and selective laser sintering 3D printing for the development of pharmaceutical dosage forms with enhanced dissolution rates and physical properties

10.1101/2021.02.13.430988 ◽

2021 ◽

Cited By ~ 1

Author(s):

Rishi Thakkar ◽

Yu Zhang ◽

Jiaxiang Zhang ◽

Mohammed Maniruzzaman

Keyword(s):

Solid State ◽

3D Printing ◽

Physical Properties ◽

Dosage Forms ◽

Flow Properties ◽

Printing Process ◽

Powder Bed ◽

Printing Processes ◽

Binder Jetting ◽

Physical Mixtures

AbstractThis study demonstrated the first case of combining novel continuous granulation with powder-based pharmaceutical 3-dimensional (3D) printing processes to enhance the dissolution rate and physical properties of a poorly water-soluble drug. Powder bed fusion (PBF) and binder jetting 3D printing processes have gained much attention in pharmaceutical dosage form manufacturing in recent times. Although powder bed-based 3D printing platforms have been known to face printing and uniformity problems due to the inherent poor flow properties of the pharmaceutical physical mixtures (feedstock). Moreover, techniques such as binder jetting currently do not provide any solubility benefits to active pharmaceutical ingredients (APIs) with poor aqueous solubility (>40% of marketed drugs). For this study, a hot-melt extrusion-based versatile granulation process equipped with UV-Vis process analytical technology (PAT) tools for the in-line monitoring of critical quality attributes (i.e., solid-state) of indomethacin was developed. The collected granules with enhanced flow properties were mixed with vinylpyrrolidone-vinyl acetate copolymer and a conductive excipient for efficient sintering. These mixtures were further characterized for their bulk properties observing an excellent flow and later subjected to a PBF-3D printing process. The physical mixtures, processed granules, and printed tablets were characterized using conventional as well as advanced solid-state characterization. These characterizations revealed the amorphous nature of the drug in the processed granules and printed tablets. Further, the in vitro release testing of the tablets with produced granules as a reference standard depicted a notable solubility advantage (100% drug released in 5 minutes at >pH 6.8) over the pure drug and the physical mixture. Our developed system known as DosePlus combines innovative continuous granulation and PBF-3D printing process which can potentially improve the physical properties of the bulk drug and formulations in comparison to when used in isolation. This process can further find application in continuous manufacturing of granules and additive manufacturing of pharmaceuticals to produce dosage forms with excellent uniformity and solubility advantage.Abstract Figure

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Exploring the Multi-Stage Effects of Material Preparation and Printing on 3D Printing Product Quality

Volume 1: Additive Manufacturing; Manufacturing Equipment and Systems; Bio and Sustainable Manufacturing ◽

10.1115/msec2019-2788 ◽

2019 ◽

Author(s):

Sahand Hajifar ◽

Ramanarayanan Purnanandam ◽

Hongyue Sun ◽

Chi Zhou

Keyword(s):

3D Printing ◽

Material Properties ◽

Good Property ◽

Metal Powders ◽

Promising Technique ◽

Printing Process ◽

Multi Stage ◽

Flexible Parts ◽

Printing Processes ◽

Material Preparation

Abstract 3D printing is a promising technique to fabricate flexible parts and reduce the supply chain. Various materials, such as metal powders, plastics, ultraviolet (UV) sensitive resins, can be fabricated from 3D printing and form the final printed part. Currently, most researchers either focus on exploring printable materials with good property or focus on the process quality control given a certain type of material. However, for many 3D printing processes, the printing process and product properties are dependent on both the material properties and process settings. To the best of the authors’ knowledge, the quantitative analysis of the interactions of material properties and printing process settings are rarely studied. In this paper, we treat the material preparation and 3D printing as different manufacturing stages, and we explore the multi-stage effects in 3D printing. In particular, we add carbon fiber to the CLEAR resin to alter the material properties for a stereolithography (SLA) 3D printing process. It is observed that the part properties are jointly affected by material properties and printing process settings. Therefore, the material property and process settings should be jointly considered for optimizing 3D printing processes.

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Optimization of Extrusion-Based 3D Printing Process Using Neural Networks for Sustainable Development

Materials ◽

10.3390/ma14112737 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2737

Author(s):

Izabela Rojek ◽

Dariusz Mikołajewski ◽

Marek Macko ◽

Zbigniew Szczepański ◽

Ewa Dostatni

Keyword(s):

Artificial Intelligence ◽

Neural Networks ◽

Risk Assessment ◽

Sustainable Development ◽

3D Printing ◽

Computational Intelligence ◽

Learning Program ◽

Printing Process ◽

Printing Processes ◽

Self Learning

Technological and material issues in 3D printing technologies should take into account sustainable development, use of materials, energy, emitted particles, and waste. The aim of this paper is to investigate whether the sustainability of 3D printing processes can be supported by computational intelligence (CI) and artificial intelligence (AI) based solutions. We present a new AI-based software to evaluate the amount of pollution generated by 3D printing systems. We input the values: printing technology, material, print weight, etc., and the expected results (risk assessment) and determine if and what precautions should be taken. The study uses a self-learning program that will improve as more data are entered. This program does not replace but complements previously used 3D printing metrics and software.

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Tensile Strength of Threaded Rods Made by 3D Printing of Polymeric Material

Materiale Plastice ◽

10.37358/mp.21.4.5526 ◽

2022 ◽

Vol 58 (4) ◽

pp. 9-18

Author(s):

Marius Ionut Ripanu ◽

Andrei Marius Mihalache ◽

Laurentiu Slatineanu ◽

Marian Mares ◽

Liviu Andrusca ◽

...

Keyword(s):

Mathematical Model ◽

Tensile Strength ◽

3D Printing ◽

Polymeric Materials ◽

Tensile Tests ◽

Printing Process ◽

Threaded Joint ◽

Maximum Deformation ◽

Tensile Forces ◽

Printing Processes

The extension of 3D printing processes for parts made of polymeric materials highlighted the possibility of manufacturing threaded surfaces through such processes. In principle, the operation of a threaded joint involves tensile forces in the threaded rod. The dimensional characteristics of the threaded surface and some input factors in the 3D printing process can influence the tensile strength of threaded rods made of polymeric materials. An experimental research aimed at the tensile behavior of a threaded joint was designed, using a plastic screw and a special steel nut. A factorial experiment was designed and implemented to identify an empirical mathematical model capable of highlighting the influence of the dimensional characteristics of the threaded surface and some of the input factors in the 3D printing process on tensile strength. The test samples from polymeric materials were manufactured by 3D printing, then subjected to tensile tests. The mathematical processing of the experimental results allowed the determination of a mathematical model that allows the inclusion of the ordering of the factors taken into account in terms of the intensity of the influence that these factors exert on the tensile strength of the threaded rods. It was found that the diameter of the threaded rod exerts the strongest influence on the tensile strength of the threaded rod obtained by 3D printing, increasing the diameter of the threaded rod causing an increase in the maximum deformation of the rod. Increasing the thread pitch leads to a decrease in the maximum deformation of the threaded rod.

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Fabrication and characterization of resistive double square loop arrays for ultra-wide bandwidth microwave absorption

Scientific Reports ◽

10.1038/s41598-021-91868-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ji-Young Jeong ◽

Je-Ryung Lee ◽

Hyeonjin Park ◽

Joonkyo Jung ◽

Doo-Sun Choi ◽

...

Keyword(s):

Sheet Resistance ◽

Manufacturing Process ◽

End Milling ◽

Milling Process ◽

Wide Bandwidth ◽

Machined Surface ◽

Array Pattern ◽

Micro End Milling ◽

Array Structures ◽

Printing Processes

AbstractMicrowave absorbers using conductive ink are generally fabricated by printing an array pattern on a substrate to generate electromagnetic fields. However, screen printing processes are difficult to vary the sheet resistance values for different regions of the pattern on the same layer, because the printing process deposits materials at the same height over the entire surface of substrate. In this study, a promising manufacturing process was suggested for engraved resistive double square loop arrays with ultra-wide bandwidth microwave. The developed manufacturing process consists of a micro-end-milling, inking, and planing processes. A 144-number of double square loop array was precisely machined on a polymethyl methacrylate workpiece with the micro-end-milling process. After engraving array structures, the machined surface was completely covered with the developed conductive carbon ink with a sheet resistance of 15 Ω/sq. It was cured at room temperature. Excluding the ink that filled the machined double square loop array, overflowed ink was removed with the planing process to achieve full filled and isolated resistive array patterns. The fabricated microwave absorber showed a small radar cross-section with reflectance less than − 10 dB in the frequency band range of 8.0–14.6 GHz.

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The influence of 3D printing process parameters on the mechanical performance of PLA polymer and its correlation with hardness

Procedia Manufacturing ◽

10.1016/j.promfg.2021.07.038 ◽

2021 ◽

Vol 54 ◽

pp. 244-249

Author(s):

Muammel M. Hanon ◽

József Dobos ◽

László Zsidai

Keyword(s):

3D Printing ◽

Process Parameters ◽

Mechanical Performance ◽

Printing Process

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Gaining a better understanding of the extrusion process in fused filament fabrication 3D printing: a review

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-021-06918-6 ◽

2021 ◽

Author(s):

Bahaa Shaqour ◽

Mohammad Abuabiah ◽

Salameh Abdel-Fattah ◽

Adel Juaidi ◽

Ramez Abdallah ◽

...

Keyword(s):

3D Printing ◽

Numerical Models ◽

Extrusion Process ◽

Analytical Models ◽

Limiting Factor ◽

Fused Filament Fabrication ◽

Promising Tool ◽

Relevant Work ◽

3D Printing Technique ◽

Required Quality

AbstractAdditive manufacturing is a promising tool that has proved its value in various applications. Among its technologies, the fused filament fabrication 3D printing technique stands out with its potential to serve a wide variety of applications, ranging from simple educational purposes to industrial and medical applications. However, as many materials and composites can be utilized for this technique, the processability of these materials can be a limiting factor for producing products with the required quality and properties. Over the past few years, many researchers have attempted to better understand the melt extrusion process during 3D printing. Moreover, other research groups have focused on optimizing the process by adjusting the process parameters. These attempts were conducted using different methods, including proposing analytical models, establishing numerical models, or experimental techniques. This review highlights the most relevant work from recent years on fused filament fabrication 3D printing and discusses the future perspectives of this 3D printing technology.

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