Effect of Autoclave Pressure and Temperature on Consolidation of Layers and Mechanical Properties of Additively Manufactured (FDM) Products with PLA

In additive manufacturing technologies, fused deposition modelling (FDM) is continuing its advancement from rapid prototyping to rapid manufacturing. However, effective usage of FDM is not performed due to the poor mechanical properties of the 3D-printed components. This drawback restricts their usage in many applications. Much research, such as reinforcing 3D-printed parts with fibers, changing printing parameters (infill density, infill concentration, extrusion temperature, nozzle diameter, layer thickness, raster angle, etc.) are aimed to increase the mechanical properties of 3D-printed parts. This research paper aims to investigate the effect of pressure and temperature on the mechanical properties and consolidation of layers of 3D-printed PLA (Polylactic Acid). Post-treatment was done using a customized autoclave. Autoclave has the capability to maintain 185 °C and 135 bar pressure. Three-dimensional-printed specimens were manufactured using the FDM process with two patterns. Later, the specimens were subjected to various post-treatment processes, then followed with testing and analysis of mechanical properties. Post-treatment process carried out by placing them in an autoclave at certain pressure and temperature conditions. To investigate the repeatability and tolerances, the test series includes a minimum of four to six test specimens. The results indicate that the concentric pattern yields the most desirable tensile, impact, and flexural strength due to the alignment of deposited rasters and better consolidation of layers with the loading direction. The pressure and temperature of the autoclave has a positive effect on the PLA samples, which helped them to reorganize the structure, hence strength properties were enhanced. The test results also compared with injection-molded samples for better understating.

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Parameters Affecting the Mechanical Properties of Three-Dimensional (3D) Printed Carbon Fiber-Reinforced Polylactide Composites

Polymers ◽

10.3390/polym12112456 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2456

Author(s):

Demei Lee ◽

Guan-Yu Wu

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

3D Printing ◽

Three Dimensional ◽

Fused Deposition Modelling ◽

Layer By Layer ◽

Fused Deposition ◽

Bed Temperature ◽

3D Printed ◽

The Impact

Three-dimensional (3D) printing is a manufacturing technology which creates three-dimensional objects layer-by-layer or drop-by-drop with minimal material waste. Despite the fact that 3D printing is a versatile and adaptable process and has advantages in establishing complex and net-shaped structures over conventional manufacturing methods, the challenge remains in identifying the optimal parameters for the 3D printing process. This study investigated the influence of processing parameters on the mechanical properties of Fused Deposition Modelling (FDM)-printed carbon fiber-filled polylactide (CFR-PLA) composites by employing an orthogonal array model. After printing, the tensile and impact strengths of the printed composites were measured, and the effects of different parameters on these strengths were examined. The experimental results indicate that 3D-printed CFR-PLA showed a rougher surface morphology than virgin PLA. For the variables selected in this analysis, bed temperature was identified as the most influential parameter on the tensile strength of CFR-PLA-printed parts, while bed temperature and print orientation were the key parameters affecting the impact strengths of printed composites. The 45° orientation printed parts also showed superior mechanical strengths than the 90° printed parts.

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Experimental investigation of strength properties of 3D printed ABS composites

E3S Web of Conferences ◽

10.1051/e3sconf/202130901148 ◽

2021 ◽

Vol 309 ◽

pp. 01148

Author(s):

Abdul Quader Shurjeel ◽

Narendra Pothula ◽

Eshwaraiah Punna

Keyword(s):

Mechanical Properties ◽

Acrylonitrile Butadiene Styrene ◽

Maximum Load ◽

Strength Properties ◽

Fused Deposition Modelling ◽

Fused Deposition ◽

Raster Angle ◽

Current Scenario ◽

Superior Mechanical Properties ◽

Butadiene Styrene

Owing to the huge demand and dependency of the industry on the lightweight and superior mechanical properties products as well as components, the materials like CF-ABS (Acrylonitrile Butadiene Styrene reinforced with carbon fibers) and PC-ABS (Acrylonitrile Butadiene Styrene reinforced with polycarbonate) have gained utmost importance in the current scenario. The present research in this paper focuses on finding the mechanical properties, mainly the tensile, compression, and flexural properties of both the above-said materials. FDM (Fused Deposition Modelling) is used as the printing technique in this research as it is the most suitable and widely used for the selected materials. After experimentation, a comparison was made between the two materials, and it is found that the PC-ABS material is stronger in compression, tension as well as in flexural at all the parametric settings. The infill percentage was observed to be proportional to the strength of the material as expected. Triangular infill geometry was more strong in compression and flexural whereas grid infill geometry was strong in tension. produced stronger mechanical properties were observed for 0-degree raster angle in all the three criteria compared to the 45 and 90-degree raster angles. When the variation of the strength of the material with the infill geometry was observed, the infill geometry was more sensitive in compression and flexural compared to that in tension. The load vs. displacement curves have been plotted to depict the maximum load and the behavior of the material in the elastic and plastic regions.

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Effect of Processing Parameters on Mechanical Properties of 3D Printed Samples

Materials Science Forum ◽

10.4028/www.scientific.net/msf.919.230 ◽

2018 ◽

Vol 919 ◽

pp. 230-235 ◽

Cited By ~ 5

Author(s):

Jaroslav Maloch ◽

Eva Hnátková ◽

Milan Žaludek ◽

Petr Krátký

Keyword(s):

Mechanical Properties ◽

Low Cost ◽

Flexural Modulus ◽

Acrylonitrile Butadiene Styrene ◽

Processing Parameters ◽

Fused Deposition Modelling ◽

Fused Deposition ◽

3D Printed ◽

Manufacturing Technologies ◽

Functional Components

3D printing technology enables the production of functional components in small quantities which can be used as end-use parts. The mechanical properties of the final product define its quality and determine its success or failure in a given application. One at the various additive manufacturing technologies - Fused Deposition Modelling is very often used due to its relatively low cost and the availability of 3D printers and thermoplastic materials. During the process, there are many factors that can affect the mechanical properties of the final product. The temperature of the extrusion nozzle and the layer thickness are two of the basic process parameters. The objective of this work is to investigate the effect of these two processing parameters on the final mechanical properties of the 3D printed samples from acrylonitrile butadiene styrene. Mechanical testing includes the tensile and flexural strength, as well as tensile and flexural modulus.

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Current State and Challenges of Natural Fibre-Reinforced Polymer Composites as Feeder in FDM-Based 3D Printing

Polymers ◽

10.3390/polym13142289 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2289

Author(s):

Nishata Royan Rajendran Royan ◽

Jie Sheng Leong ◽

Wai Nam Chan ◽

Jie Ren Tan ◽

Zainon Sharmila Binti Shamsuddin

Keyword(s):

Mechanical Properties ◽

Natural Fibre ◽

Critical Discussion ◽

Fused Deposition Modelling ◽

Preparation Methods ◽

Fused Deposition ◽

Current State ◽

Future Challenges ◽

Raster Angle ◽

Fibre Reinforced Polymer

As one of the fastest-growing additive manufacturing (AM) technologies, fused deposition modelling (FDM) shows great potential in printing natural fibre-reinforced composites (NFRC). However, several challenges, such as low mechanical properties and difficulty in printing, need to be overcome. Therefore, the effort to improve the NFRC for use in AM has been accelerating in recent years. This review attempts to summarise the current approaches of using NFRC as a feeder for AM. The effects of fibre treatments, composite preparation methods and addition of compatibilizer agents were analysed and discussed. Additionally, current methods of producing feeders from NFRCs were reviewed and discussed. Mechanical property of printed part was also dependent on the printing parameters, and thus the effects of printing temperature, layer height, infill and raster angle were discussed, and the best parameters reported by other researchers were identified. Following that, an overview of the mechanical properties of these composites as reported by various researchers was provided. Next, the use of optimisation techniques for NFRCs was discussed and analysed. Lastly, the review provided a critical discussion on the overall topic, identified all research gaps present in the use of NFRC for AM processes, and to overcome future challenges.

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Influence of the Infill Geometry of 3D-Printed Tablets on Drug Dissolution

Medical Sciences Forum ◽

10.3390/msf2021005015 ◽

2021 ◽

Vol 5 (1) ◽

pp. 15

Author(s):

Nuno Venâncio ◽

Gabriela G. Pereira ◽

João F. Pinto ◽

Ana I. Fernandes

Keyword(s):

Three Dimensional ◽

Drug Dissolution ◽

Fused Deposition Modelling ◽

Three Dimensional Printing ◽

Preliminary Results ◽

Fused Deposition ◽

3D Printed ◽

Dimensional Printing ◽

Hot Melt ◽

Patient Centric

Patient-centric therapy is especially important in pediatrics and may be attained by three-dimensional printing. Filaments containing 30% w/w of theophylline were produced by hot-melt extrusion and printed using fused deposition modelling to produce tablets. Here, preliminary results evaluating the effect of infill geometry (cross, star, grid) on drug content and release are reported.

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Investigations of process parameters during dissolution studies of drug loaded 3D printed tablets

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1177/0954411921993582 ◽

2021 ◽

pp. 095441192199358

Author(s):

Varun Sharma ◽

Khaja Moinuddin Shaik ◽

Archita Choudhury ◽

Pramod Kumar ◽

Prateek Kala ◽

...

Keyword(s):

Dissolution Rate ◽

Process Parameters ◽

Empirical Relation ◽

Three Dimensional ◽

Critical Parameters ◽

Fused Deposition Modelling ◽

Fused Deposition ◽

Rate Of Dissolution ◽

3D Printed ◽

Percentage Release

The present research paper attempts to study the effect of different process parameters on the dissolution rate during 3D printed tablets. Three-dimensional printing has the potential of serving tailored made tablets to cater personalized drug delivery systems. Fluorescein loaded PVA filaments through impregnation route was used to fabricate tablets based on Taguchi based design of experimentation using Fused Deposition Modelling (FDM). The effect of print speed, infill percentage and layer thickness were analyzed to study the effect on rate of dissolution. Infill percentage followed by print speed were found to be critical parameters affecting dissolution rate. The data analysis provided an insight into the study of interaction among different 3D printing parameters to develop an empirical relation for percentage release of the drug in human body.

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Effect of heat treatment on mechanical properties of 3D printed polylactic acid parts

Materials Testing ◽

10.1515/mt-2020-0010 ◽

2021 ◽

Vol 63 (1) ◽

pp. 73-78

Author(s):

Pulkin Gupta ◽

Sudha Kumari ◽

Abhishek Gupta ◽

Ankit Kumar Sinha ◽

Prashant Jindal

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Polylactic Acid ◽

Recrystallization Temperature ◽

Fused Deposition Modelling ◽

Fused Deposition ◽

Dog Bone ◽

Heat Treated ◽

Maximum Decrease ◽

3D Printed

Abstract Fused deposition modelling (FDM) is a layer-by-layer manufacturing process type of 3D-printing (3DP). Significant variation in the mechanical properties of 3D printed specimens is observed because of varied process parameters and interfacial bonding between consecutive layers. This study investigates the influence of heat treatment on the mechanical strength of FDM 3D printed Polylactic acid (PLA) parts with constant 3DP parameters and ambient conditions. To meet the objectives, 7 sets, each containing 5 dog-bone shaped samples, were fabricated from commercially available PLA filament. Each set was subjected to heat treatment at a particular temperature for 1 h and cooled in the furnace itself, while one set was left un-treated. The temperature for heat treatment (Th) varied from 30 °C to 130 °C with increments of 10 °C. The heat-treated samples were characterized under tensile loading of 400 N and mechanical properties like Young’s modulus (E), Strain % ( ε ) and Stiffness (k) were evaluated. On comparing the mechanical properties of heat-treated samples to un-treated samples, significant improvements were observed. Heat treatment also altered the geometries of the samples. Mechanical properties improved by 4.88 % to 10.26 % with the maximum being at Th of 110 °C and below recrystallization temperature (Tr) of 65 °C. Deformations also decreased significantly at higher temperatures above 100 °C, by a maximum of 36.06 %. The dimensions of samples showed a maximum decrease of 1.08 % in Tr range and a maximum decrease of 0.31 % in weight at the same temperature. This study aims to benefit the society by establishing suitable Th to recover the lost strength in PLA based FDM 3D printed parts.

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3D Printing of Thermo-Sensitive Drugs

Pharmaceutics ◽

10.3390/pharmaceutics13091524 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1524

Author(s):

Sadikalmahdi Abdella ◽

Souha H. Youssef ◽

Franklin Afinjuomo ◽

Yunmei Song ◽

Paris Fouladian ◽

...

Keyword(s):

3D Printing ◽

Three Dimensional ◽

Fused Deposition Modelling ◽

Future Directions ◽

Digital Light Processing ◽

Fused Deposition ◽

Printing Technique ◽

3D Printed ◽

Semi Solid ◽

Selection Of

Three-dimensional (3D) printing is among the rapidly evolving technologies with applications in many sectors. The pharmaceutical industry is no exception, and the approval of the first 3D-printed tablet (Spiratam®) marked a revolution in the field. Several studies reported the fabrication of different dosage forms using a range of 3D printing techniques. Thermosensitive drugs compose a considerable segment of available medications in the market requiring strict temperature control during processing to ensure their efficacy and safety. Heating involved in some of the 3D printing technologies raises concerns regarding the feasibility of the techniques for printing thermolabile drugs. Studies reported that semi-solid extrusion (SSE) is the commonly used printing technique to fabricate thermosensitive drugs. Digital light processing (DLP), binder jetting (BJ), and stereolithography (SLA) can also be used for the fabrication of thermosensitive drugs as they do not involve heating elements. Nonetheless, degradation of some drugs by light source used in the techniques was reported. Interestingly, fused deposition modelling (FDM) coupled with filling techniques offered protection against thermal degradation. Concepts such as selection of low melting point polymers, adjustment of printing parameters, and coupling of more than one printing technique were exploited in printing thermosensitive drugs. This systematic review presents challenges, 3DP procedures, and future directions of 3D printing of thermo-sensitive formulations.

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Mechanical Properties of Diamond Schwarzites: From Atomistic Models to 3D-Printed Structures

MRS Advances ◽

10.1557/adv.2020.175 ◽

2020 ◽

Vol 5 (33-34) ◽

pp. 1775-1781 ◽

Cited By ~ 1

Author(s):

Levi C. Felix ◽

Vladimir Gaál ◽

Cristiano F. Woellner ◽

Varlei Rodrigues ◽

Douglas S. Galvao

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Uniaxial Compression ◽

Chemical Vapour ◽

Md Simulations ◽

Atomic Model ◽

Fused Deposition Modelling ◽

Fused Deposition ◽

Structural Applications ◽

3D Printed

ABSTRACTTriply Periodic Minimal Surfaces (TPMS) possess locally minimized surface area under the constraint of periodic boundary conditions. Different families of surfaces were obtained with different topologies satisfying such conditions. Examples of such families include Primitive (P), Gyroid (G) and Diamond (D) surfaces. From a purely mathematical subject, TPMS have been recently found in materials science as optimal geometries for structural applications. Proposed by Mackay and Terrones in 1991, schwarzites are 3D crystalline porous carbon nanocrystals exhibiting a TPMS-like surface topology. Although their complex topology poses serious limitations on their synthesis with conventional nanoscale fabrication methods, such as Chemical Vapour Deposition (CVD), schwarzites can be fabricated by Additive Manufacturing (AM) techniques, such as 3D Printing. In this work, we used an optimized atomic model of a schwarzite structure from the D family (D8bal) to generate a surface mesh that was subsequently used for 3D-printing through Fused Deposition Modelling (FDM). This D schwarzite was 3D-printed with thermoplastic PolyLactic Acid (PLA) polymer filaments. Mechanical properties under uniaxial compression were investigated for both the atomic model and the 3D-printed one. Fully atomistic Molecular Dynamics (MD) simulations were also carried out to investigate the uniaxial compression behavior of the D8bal atomic model. Mechanical testings were performed on the 3D-printed schwarzite where the deformation mechanisms were found to be similar to those observed in MD simulations. These results are suggestive of a scale-independent mechanical behavior that is dominated by structural topology.

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Anisotropy Evaluation of Different Raster Directions, Spatial Orientations, and Fill Percentage of 3D Printed PETG Tensile Test Specimens

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.821.167 ◽

2019 ◽

Vol 821 ◽

pp. 167-173 ◽

Cited By ~ 5

Author(s):

Muammel M. Hanon ◽

Róbert Marczis ◽

László Zsidai

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Tensile Test ◽

Fused Deposition Modelling ◽

Elongation At Break ◽

Know How ◽

Fused Deposition ◽

Test Pieces ◽

3D Printed ◽

Fill Percentage

In this paper, the mechanical properties of Polyethylene terephthalate-glycol (PETG) tensile test specimens have been investigated. The test pieces were prepared using fused deposition modelling (FDM) 3D printing technology. Three print settings were examined which are: raster direction angles, print orientations, and infill percentage and patterns in order to evaluate the anisotropy of objects when employing FDM print method. The variations in stress-strain curves, tensile strength values and elongation at break among the tested samples were studied and compared. Illustration for the broken specimens after the tensile test was accomplished to know how the test pieces printed with various parameters were fractured. A comparison with some previous results regarding the elongation at break has been carried out.

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