3D Printed Injection Molds Using Various 3D Printing Technologies

This paper explores the possibility of using different 3d printing methods and materials in the production of polymer molds for injection molding applications. A mold producing a cube was designed using a commercial software. Following the standard 3d printing process, injection molds which could produce a cube were printed using different 3d printing materials and 3d printing technologies. The 3d printing technologies used were Stereolithography (SLA), Polyjet and Fused Filament Fabrication (FFF). A bench-top injection molding machine was used to inject polylactic acid (PLA) in these molds. The quality of the injected parts in terms of dimensional accuracy has been investigated. In some cases, the damage mechanism of the polymer molds has also been observed.

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Fused Filament Fabrication 3D Printed Polylactic Acid Electroosmotic Pumps

Lab on a Chip ◽

10.1039/d1lc00452b ◽

2021 ◽

Author(s):

Liang Wu ◽

Stephen Beirne ◽

Joan-Marc Cabot Canyelles ◽

Brett Paull ◽

Gordon G. Wallace ◽

...

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Polylactic Acid ◽

Fused Filament Fabrication ◽

Flexible Approach ◽

Electroosmotic Pump ◽

3D Printed ◽

Electroosmotic Pumps

Additive manufacturing (3D printing) offers a flexible approach for the production of bespoke microfluidic structures such as the electroosmotic pump. Here a readily accessible fused filament fabrication (FFF) 3D printing...

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Enhancement of the Compressive Strength of 3D-Printed Polylactic Acid(PLA) by Controlling Internal Pattern

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1023.75 ◽

2021 ◽

Vol 1023 ◽

pp. 75-81

Author(s):

Aappo Mustakangas ◽

Atef Hamada ◽

Antti Järvenpää

Keyword(s):

Compressive Strength ◽

3D Printing ◽

Polylactic Acid ◽

Optical Microscope ◽

Fused Filament Fabrication ◽

Loading Direction ◽

Compressive Flow ◽

3D Printed ◽

Cost Efficient ◽

Loading Axis

Cost-efficient 3D-printing can create a lot of new opportunities in engineering as it enables rapid prototyping of models and functional parts. In the present study, Polylactic acid (PLA) cubic specimens with different types of infill patterns (IPs), rectilinear, grid and cuboid, were additively manufactured by Fused Filament Fabrication 3D-printing. The PLA cubes are fabricated with one perimeter and different IPs density (10, 20, and 30%). Subsequently, the compressive strengths of the PLA materials were measured in two loading directions, i.e., the layers building direction is parallel (PD) to the loading axis and perpendicular (ND) to the loading direction. An optical microscope was used to examine the deformed IPs in both loading directions. The compressive flow stress curves of the PLA cubes infilled with rectilinear and grid patterns exhibited strong fluctuations with lower compressive strengths in the loading direction along ND. The PLA with 30% grid IP revealed a superior strength of ~12 kN in the loading direction along PD. On the contrary, the same material exhibited a worst compressive strength 3 kN along ND.

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Effect of Porosity and Crystallinity on 3D Printed PLA Properties

Polymers ◽

10.3390/polym11091487 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1487 ◽

Cited By ~ 19

Author(s):

Yuhan Liao ◽

Chang Liu ◽

Bartolomeo Coppola ◽

Giuseppina Barra ◽

Luciano Di Maio ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Additive Manufacturing ◽

3D Printing ◽

Polylactic Acid ◽

Complex Geometry ◽

Fused Filament Fabrication ◽

3D Printed ◽

Physical Changes ◽

Crystalline Forms

Additive manufacturing (AM) is a promising technology for the rapid tooling and fabrication of complex geometry components. Among all AM techniques, fused filament fabrication (FFF) is the most widely used technique for polymers. However, the consistency and properties control of the FFF product remains a challenging issue. This study aims to investigate physical changes during the 3D printing of polylactic acid (PLA). The correlations between the porosity, crystallinity and mechanical properties of the printed parts were studied. Moreover, the effects of the build-platform temperature were investigated. The experimental results confirmed the anisotropy of printed objects due to the occurrence of orientation phenomena during the filament deposition and the formation both of ordered and disordered crystalline forms (α and δ, respectively). A heat treatment post-3D printing was proposed as an effective method to improve mechanical properties by optimizing the crystallinity (transforming the δ form into the α one) and overcoming the anisotropy of the 3D printed object.

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Research of 3D Printing Modes of Feedstock for Metal Injection Molding

Materials Science Forum ◽

10.4028/www.scientific.net/msf.992.461 ◽

2020 ◽

Vol 992 ◽

pp. 461-466

Author(s):

A.Yu. Korotchenko ◽

D.E. Khilkov ◽

M.V. Tverskoy ◽

A.A. Khilkova

Keyword(s):

3D Printing ◽

Injection Molding ◽

Metal Injection Molding ◽

Small Scale ◽

Print Quality ◽

Scale Production ◽

Fused Filament Fabrication ◽

Factors Affecting ◽

The Cost

In this work, to reduce the cost of production of parts using injection molding metal technology (MIM technology), it is proposed to use additive technologies (AT) for the manufacture of green parts. The use of AT allows us to abandon expensive molds and expand the field of use of the MIM of technology in single and small-scale production. For manufacture of green parts, the technology of manufacturing fused filament (Fused Filament Fabrication – FFF) is offered. The original composition of the metal powder mix (feedstock) and the filament manufacturing modes for 3D printing have been developed for the FFF technology. The cost of filament is much lower than its analogs. The factors affecting the print quality of green part are considered. All factors are divided into two groups depending on the possibility of their change during printing. The research of the influence of the coefficient filament supply on the geometry of green parts during 3D printing is presented.

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Non-Contact Multiscale Analysis of a DPP 3D-Printed Injection Die for Investment Casting

Materials ◽

10.3390/ma14226758 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6758

Author(s):

Arkadiusz Kroma ◽

Michał Mendak ◽

Michał Jakubowicz ◽

Bartosz Gapiński ◽

Paweł Popielarski

Keyword(s):

3D Printing ◽

Investment Casting ◽

Measurement Techniques ◽

Dimensional Accuracy ◽

Printing Technology ◽

Measurement Systems ◽

Contact Measurement ◽

3D Printing Technology ◽

3D Printed

The investment casting method supported with 3D-printing technology, allows the production of unit castings or prototypes with properties most similar to those of final products. Due to the complexity of the process, it is very important to control the dimensions in the initial stages of the process. This paper presents a comparison of non-contact measurement systems applied for testing of photopolymer 3D-printed injection die used in investment casting. Due to the required high quality of the surface parameters, the authors decided to use the DPP (Daylight Polymer Printing) 3D-printing technology to produce an analyzed injection die. The X-ray CT, Structured blue-light scanner and focus variation microscope measurement techniques were used to avoid any additional damages to the injection die that may arise during the measurement. The main objective of the research was to analyze the possibility of using non-contact measurement systems as a tool for analyzing the quality of the surface of a 3D-printed injection die. Dimensional accuracy analysis, form and position deviations, defect detection, and comparison with a CAD model were carried out.

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Evaluation of the Dimensional Accuracy of 3D-Printed Anatomical Mandibular Models Using FFF, SLA, SLS, MJ, and BJ Printing Technology

Journal of Clinical Medicine ◽

10.3390/jcm9030817 ◽

2020 ◽

Vol 9 (3) ◽

pp. 817 ◽

Cited By ~ 9

Author(s):

Bilal Msallem ◽

Neha Sharma ◽

Shuaishuai Cao ◽

Florian S. Halbeisen ◽

Hans-Florian Zeilhofer ◽

...

Keyword(s):

3D Printing ◽

Accuracy Assessment ◽

Selective Laser Sintering ◽

Dimensional Accuracy ◽

Rapid Progression ◽

Fused Filament Fabrication ◽

Printing Technology ◽

3D Printed ◽

Binder Jetting ◽

Intended Use

With the rapid progression of additive manufacturing and the emergence of new 3D printing technologies, accuracy assessment is mostly being performed on isosymmetric-shaped test bodies. However, the accuracy of anatomic models can vary. The dimensional accuracy of root mean square values in terms of trueness and precision of 50 mandibular replicas, printed with five common printing technologies, were evaluated. The highest trueness was found for the selective laser sintering printer (0.11 ± 0.016 mm), followed by a binder jetting printer (0.14 ± 0.02 mm), and a fused filament fabrication printer (0.16 ± 0.009 mm). However, highest precision was identified for the fused filament fabrication printer (0.05 ± 0.005 mm) whereas other printers had marginally lower values. Despite the statistically significance (p < 0.001), these differences can be considered clinically insignificant. These findings demonstrate that all 3D printing technologies create models with satisfactory dimensional accuracy for surgical use. Since satisfactory results in terms of accuracy can be reached with most technologies, the choice should be more strongly based on the printing materials, the intended use, and the overall budget. The simplest printing technology (fused filament fabrication) always scored high and thus is a reliable choice for most purposes.

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Fused Filament Fabrication Three-Dimensional Printing Multi-Functional of Polylactic Acid/Carbon Black Nanocomposites

C – Journal of Carbon Research ◽

10.3390/c7030052 ◽

2021 ◽

Vol 7 (3) ◽

pp. 52

Author(s):

Nectarios Vidakis ◽

Markos Petousis ◽

Emmanuel Velidakis ◽

Nikolaos Mountakis ◽

Peder Erik Fischer-Griffiths ◽

...

Keyword(s):

3D Printing ◽

Carbon Black ◽

Polylactic Acid ◽

Complex Geometry ◽

Three Dimensional ◽

Antibacterial Properties ◽

Fused Filament Fabrication ◽

Melt Mixing ◽

Screening Process ◽

3D Printed

Conductive Polymer Composites (CPCs) have recently gained an extensive scientific interest as feedstock materials in Fused Filament Fabrication (FFF) Three-dimensional (3D) printing. Polylactic Acid (PLA), widely used in FFF 3D printing, as well as its Carbon Black (CB) nanocomposites at different weight percentage (wt.%) filler loadings (0.5, 1.0, 2.5 and 5.0 wt.%), were prepared via a melt mixing filament extrusion process in this study and utilized to manufacture FFF 3D printed specimens. The nanocomposites were examined for their electrical conductivity. The highest loaded 3D printed CPC (5.0 wt.%) was tested as an electrothermal Joule heating device. Static tensile, flexural, Charpy’s impact and Vickers microhardness mechanical properties were investigated for the neat and PLA/CB 3D printed nanocomposites. Dynamic Mechanical Analysis (DMA) revealed a stiffening mechanism for the PLA/CB nanocomposites. Scanning Electron Microscopy (SEM) elucidated the samples’ internal and external microstructural characteristics. The PLA/CB 5.0 wt.% nanocomposite demonstrated also antibacterial properties, when examined with a screening process, against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). It can be envisaged that the 3D printed PLA/CB CPCs exhibited a multi-functional performance, and could open new avenues towards low-cost personalized biomedical objects with complex geometry, amongst others, i.e., surgery tools, splints, wearables, etc.

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Biomimetic Design of 3D Printed Tissue-engineered bone Constructs

Current Nanoscience ◽

10.2174/1573413716999201022191909 ◽

2020 ◽

Vol 16 ◽

Author(s):

Wei Liu ◽

Shifeng Liu ◽

Yunzhe Li ◽

Peng Zhou ◽

Qian ma

Keyword(s):

Tissue Engineering ◽

3D Printing ◽

Advanced Materials ◽

Bionic Design ◽

Material Interfaces ◽

Precise Control ◽

Cell Printing ◽

Biomimetic Scaffolds ◽

3D Printed

Abstract:: Surgery to repair damaged tissue, which is caused by disease or trauma, is being carried out all the time, and a desirable treatment is compelling need to regenerate damaged tissues to further improve the quality of human health. Therefore, more and more research focus on exploring the most suitable bionic design to enrich available treatment methods. 3D-printing, as an advanced materials processing approach, holds promising potential to create prototypes with complex constructs that could reproduce primitive tissues and organs as much as possible or provide appropriate cell-material interfaces. In a sense, 3D printing promises to bridge between tissue engineering and bionic design, which can provide an unprecedented personalized recapitulation with biomimetic function under the precise control of the composition and spatial distribution of cells and biomaterials. This article describes recent progress in 3D bionic design and the potential application prospect of 3D printing regenerative medicine including 3D printing biomimetic scaffolds and 3D cell printing in tissue engineering.

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Choice and Exchange of Lubricating Oil for Injection Molding Machine

Recent Patents on Mechanical Engineering ◽

10.2174/2212797612666190730145515 ◽

2019 ◽

Vol 12 (4) ◽

pp. 378-382

Author(s):

Shan Syedhidayat ◽

Quan Wang ◽

Al-Hadad M.A.A. Mohsen ◽

Jinrong Wang

Keyword(s):

Injection Molding ◽

Dimensional Accuracy ◽

Low Noise ◽

Working Environment ◽

Lubricating Oil ◽

Lubrication System ◽

Molding Machine ◽

Oil And Grease ◽

Injection Molding Machine ◽

The Stability

Background: One of the most common manufacturing equipment for polymer product is injection molding machine. In order to ensure the precise, stable and continuous operation of the injection molding machine, the maintenance of the lubrication system must be done well. The stability, reliability, rationality and low noise performance of the lubrication system of injection molding machine directly affect the quality of injection products, dimensional accuracy, molding cycle, working environment and maintenance. Objective: The purpose of this study is to introduce the methods of choice, maintenance of lubricating oil for injection molding machine from many literatures and patents in the recent years, such as lubricating oil device, lubricating composite and structure. Methods: An example of the 260M5 automatic injection molding machine is introduced for the inspection and maintenance of the lubrication system including lubricating oil and lubricating grease. Results: To ensure the lubrication of the injection molding machine, it needs to strictly observe the lubrication time and modulus of the injection molding machine. It needs to strictly control the temperature rise of the lubricating oil and select the correct lubricating oil and grease to ensure the lubrication quality. Conclusion: In the operation of the injection molding machine, it is necessary to check that the lubricating oil is sufficient and the lubricating points are working properly. It ensures sufficient lubrication of the injection molding machine and strictly observes the lubrication time and modulus of the injection molding machine. The stored lubricating oil should be sealed well to prevent air pollution.

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The Direct 3D Printing of Functional PEEK/Hydroxyapatite Composites via a Fused Filament Fabrication Approach

Polymers ◽

10.3390/polym13040545 ◽

2021 ◽

Vol 13 (4) ◽

pp. 545

Author(s):

Krzysztof Rodzeń ◽

Preetam K. Sharma ◽

Alistair McIlhagger ◽

Mozaffar Mokhtari ◽

Foram Dave ◽

...

Keyword(s):

Tensile Strength ◽

3D Printing ◽

Selective Laser Sintering ◽

Fused Filament Fabrication ◽

Bone Apposition ◽

Innovative Solutions ◽

3D Printed ◽

Work Samples ◽

Viable Approach ◽

Crystalline Domains

The manufacture of polyetheretherketone/hydroxyapatite (PEEK/HA) composites is seen as a viable approach to help enhance direct bone apposition in orthopaedic implants. A range of methods have been used to produce composites, including Selective Laser Sintering and injection moulding. Such techniques have drawbacks and lack flexibility to manufacture complex, custom-designed implants. 3D printing gets around many of the restraints and provides new opportunities for innovative solutions that are structurally suited to meet the needs of the patient. This work reports the direct 3D printing of extruded PEEK/HA composite filaments via a Fused Filament Fabrication (FFF) approach. In this work samples are 3D printed by a custom modified commercial printer Ultimaker 2+ (UM2+). SEM-EDX and µCT analyses show that HA particles are evenly distributed throughout the bulk and across the surface of the native 3D printed samples, with XRD highlighting up to 50% crystallinity and crystalline domains clearly observed in SEM and HR-TEM analyses. This highlights the favourable temperature conditions during 3D printing. The yield stress and ultimate tensile strength obtained for all the samples are comparable to human femoral cortical bone. The results show how FFF 3D printing of PEEK/HA composites up to 30 wt% HA can be achieved.

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