Influence of Build Orientation, Geometry and Artificial Saliva Aging on the Mechanical Properties of 3D Printed Poly(ε-caprolactone)

Additive manufacturing of polymers has evolved from rapid prototyping to the production of functional components/parts with applications in distinct areas, ranging from health to aeronautics. The possibility of producing complex customized geometries with less environmental impact is one of the critical factors that leveraged the exponential growth of this processing technology. Among the several processing parameters that influence the properties of the parts, the geometry (shape factor) is amid less reported. Considering the geometric complexity of the mouth, including the uniqueness of each teething, this study can contribute to a better understanding of the performance of polymeric devices used in the oral environment for preventive, restorative, and regenerative therapies. Thus, this work aims to evaluate 3D printed poly(ε-caprolactone) mechanical properties with different build orientations and geometries. Longitudinal and transversal toolpaths produced specimens with parallelepiped and tubular geometry. Moreover, as it is intended to develop devices for dentistry, the influence of artificial saliva on mechanical properties was determined. The research concluded that the best mechanical properties are obtained for parallelepiped geometry with a longitudinal impression and that aging in artificial saliva negatively influences all the mechanical properties evaluated in this study.

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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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A study of the mechanical properties of coated papers using elastica stiffness and low-load indentation

TAPPI Journal ◽

10.32964/tj10.10.41 ◽

2011 ◽

Vol 10 (10) ◽

pp. 41-48 ◽

Cited By ~ 1

Author(s):

ROBERT RIOUX ◽

DOUGLAS W. BOUSFIELD ◽

NICK TRIANTAFILLOPOULOS

Keyword(s):

Mechanical Properties ◽

Shape Factor ◽

Coating Layer ◽

Processing Parameters ◽

Dynamic Mechanical Properties ◽

Coated Papers ◽

Low Load ◽

Pigment Type ◽

Drying Conditions ◽

Styrene Butadiene

Mechanical properties of coated papers, and specifically of a coating layer, are important during printing and converting operations. Those properties can be associated with several paper defects, such as coating pick, cracking at the fold, and dusting at the slitter. We introduced two dynamic tests for quantifying coating dynamic mechanical properties: (1) a closed loop elastica test and (2) a low-load indenter test. To evaluate these tests, several coatings on lightweight coated paper were produced with varying compositions and made under variable laboratory processing parameters. Pigment type, starch level, binder glass transition temperature, binder particle size, binder level, and drying method were varied. The moduli of a coating layer were extracted from elastica stiffness using a two-layer model. The shape factor of kaolin coating pigments had a significant effect; large shape factor led to increasing in-plane moduli but decreased elastic moduli measured in compression. The level of starch addition proportionally imparted stiffness. Laboratory drying conditions and styrene-butadiene latex type had a small effect.

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FDM 3D Printing of Polymers Containing Natural Fillers: A Review of their Mechanical Properties

Polymers ◽

10.3390/polym11071094 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1094 ◽

Cited By ~ 53

Author(s):

Valentina Mazzanti ◽

Lorenzo Malagutti ◽

Francesco Mollica

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Fused Deposition Modeling ◽

Natural Fibers ◽

Acrylonitrile Butadiene Styrene ◽

Processing Parameters ◽

Fused Deposition ◽

Additive Formulation ◽

Deposition Modeling ◽

3D Printed

As biodegradable thermoplastics are more and more penetrating the market of filaments for fused deposition modeling (FDM) 3D printing, fillers in the form of natural fibers are convenient: They have the clear advantage of reducing cost, yet retaining the filament biodegradability characteristics. In plastics that are processed through standard techniques (e.g., extrusion or injection molding), natural fibers have a mild reinforcing function, improving stiffness and strength, it is thus interesting to evaluate whether the same holds true also in the case of FDM produced components. The results analyzed in this review show that the mechanical properties of the most common materials, i.e., acrylonitrile-butadiene-styrene (ABS) and PLA, do not benefit from biofillers, while other less widely used polymers, such as the polyolefins, are found to become more performant. Much research has been devoted to studying the effect of additive formulation and processing parameters on the mechanical properties of biofilled 3D printed specimens. The results look promising due to the relevant number of articles published in this field in the last few years. This notwithstanding, not all aspects have been explored and more could potentially be obtained through modifications of the usual FDM techniques and the devices that have been used so far.

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Influence of processing parameters on mechanical properties of a 3D‐printed trabecular bone microstructure

Journal of Biomedical Materials Research Part B Applied Biomaterials ◽

10.1002/jbm.b.34363 ◽

2019 ◽

Vol 108 (1) ◽

pp. 38-47 ◽

Cited By ~ 1

Author(s):

Morteza Amini ◽

Andreas Reisinger ◽

Dieter H. Pahr

Keyword(s):

Mechanical Properties ◽

Trabecular Bone ◽

Processing Parameters ◽

Bone Microstructure ◽

Trabecular Bone Microstructure ◽

3D Printed

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Poly(Lactic) Acid Reinforced with Alkaline Lignin Biocomposites Prepared by Thermal Extrusion for Sustainable 3D Printing Process

Journal of Physics Conference Series ◽

10.1088/1742-6596/2129/1/012003 ◽

2021 ◽

Vol 2129 (1) ◽

pp. 012003

Author(s):

Nurul Amirah Abd Rahman ◽

Hazleen Anuar ◽

Fathilah Ali ◽

Jonghwan Suhr

Keyword(s):

Mechanical Properties ◽

Lactic Acid ◽

3D Printing ◽

Natural Fiber ◽

Tensile Tests ◽

Poly Lactic Acid ◽

Fused Filament Fabrication ◽

3D Printed ◽

Functional Components ◽

Thermal Extrusion

Abstract The focus of this work is the mechanical characterization of biomaterials produced by 3D printing based on fused filament fabrication (FFF) process that has been mainly used for prototype rather than functional components due to the limited mechanical properties of pure thermoplastics parts. Addition of reinforcements from natural fiber has been adopted to improve the mechanical properties of the 3D printed parts. In this study, alkaline lignin powder that has been extracted from oil palm empty fruit bunches (OPEFB) via alkaline extraction process were used as filler in the production of biocomposites with poly(lactic) acid (PLA). Poly(lactic) acid filaments filled with 1% of alkaline lignin powder and has been compared with the presence of 5% of epoxidized palm oil (EPO) by means of thermal extrusion and further proceed with 3D printing. The samples were mechanically characterized using tensile tests and the fractography were observed. Tensile test that has been done on the filaments reveal that the filament with addition of lignin and EPO shows improved mechanical properties with higher tensile strength as well as lower stiffness. The 3D printed samples of the filament compositions also exhibit similar trend where the said filament has the best mechanical properties when the EPO is incorporated in the filament.

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The orthotropic viscoelastic characterisation of sub-zero 3D-printed poly(vinyl alcohol) cryogel

MRS Advances ◽

10.1557/s43580-021-00086-1 ◽

2021 ◽

Author(s):

J. P. Crolla ◽

M. M. Britton ◽

D. M. Espino ◽

L. E. J. Thomas-Seale

Keyword(s):

Mechanical Properties ◽

Vinyl Alcohol ◽

Complex Geometry ◽

Processing Parameters ◽

Poly Vinyl Alcohol ◽

Additive Manufacture ◽

Storage And Loss Moduli ◽

3D Printed ◽

Orthotropic Properties ◽

The Impact

Abstract Poly(vinyl alcohol) cryogel (PVA) is a versatile biomaterial used to replicate the biomechanics of tissues. Additive manufacture (AM) at sub-zero (°C) temperatures enables the manufacture of PVA with complex geometry; however, the effect of processing parameters on the mechanical properties of PVA has not been evaluated. The aim of this study is to understand the impact of print nozzle diameter and orientation on the viscoelastic mechanical properties of PVA. Samples of sub-zero AM PVA, with different filament thicknesses, were tested under tension relative to the print direction, to calculate the storage and loss moduli. As the nozzle size was decreased, AM PVA exhibited more pronounced orthotropic properties; the smallest size showed a 33% decrease in storage moduli when tested perpendicular to the print direction, as opposed to parallel. This study has demonstrated the ability of sub-zero AM to tailor the orthotropic properties of PVA. Graphic abstract

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3D printing of PLA and PMMA multilayered model polymers: an innovative approach for a better-controlled pellet multi-extrusion process

10.25518/esaform21.1024 ◽

2021 ◽

Author(s):

Mohamed Yousfi ◽

Ahmed Belhadj ◽

Khalid Lamnawar ◽

Abderrahim Maazouz

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Processing Parameters ◽

Extrusion Process ◽

Thermomechanical Properties ◽

Three Point Bending ◽

Short Beam ◽

Multilayered Systems ◽

Chamber Temperature ◽

3D Printed

The present work deals with the 3D printing of multimaterials based on PLA/PMMA multilayers directly obtained from pellets. This polymer pair was chosen for their miscibility at the melt state and synergistic properties (i.e., to improve and weather tune the temperature resistance, transparency and thermomechanical properties of their PLA-based materials). Thus, 3D-printed parts with repeating PMMA/PLA/PMMA layers in the Z building direction were successfully prepared in different numbers but maintaining the same composition. The main objective was to better understand the interface/interphase properties developed during this innovative processing. First, further physicochemical and dynamic thermomechanical characterizations were performed. Second, the effects of multi-extrusion 3D printing processing parameters on the thermal stability of PLA, PMMA and their printed specimens were analyzed by GPC. Then, the structuralrheological and mechanical properties of the multilayered systems were investigated in comparison to their equivalent blend. The effects of flow kinematics during extrusion as well as printing chamber temperature (PCT) and infill density (ID) were specifically studied and rationalized. The triggered interfaces were characterized by SEM and subjected to flexural and short-beam three-point bending experiments that proved their dramatic influence on the final mechanical properties. The ultimate aim of this study is to enable successful control of the interfaces/interphases obtained in these 3D-printed PLA/PMMA systems in comparison to other forming processes.

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Surface Modification and its Influence on the Microstructure and Creep Resistance of Nickel Based Superalloy René 77 / Modyfikacja Powierzchniowa Oraz Jej Wpływ Na Mikrostrukture I Wytrzymałosc Na Pełzanie Odlewów Z Nadstopu Niklu Ren´E 77

Archives of Metallurgy and Materials ◽

10.2478/v10172-012-0157-6 ◽

2013 ◽

Vol 58 (1) ◽

pp. 95-98 ◽

Cited By ~ 2

Author(s):

M. Zielinska ◽

J. Sieniawski

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Surface Modification ◽

Turbine Blades ◽

Processing Parameters ◽

Grain Structure ◽

Creep Tests ◽

Cobalt Aluminate ◽

Nickel Based Superalloy ◽

Average Grain Size

Superalloy René 77 is very wide used for turbine blades, turbine disks of aircraft engines which work up to 1050°C. These elements are generally produced by the investment casting method. Turbine blades produced by conventional precision casting methods have coarse and inhomogeneous grain structure. Such a material often does not fulfil basic requirements, which concern mechanical properties for the stuff used in aeronautical engineering. The incorporation of controlled grain size improved mechanical properties. This control of grain size in the casting operation was accomplished by the control of processing parameters such as casting temperature, mould preheating temperature, and the use of grain nucleates in the face of the mould. For nickel and cobalt based superalloys, it was found that cobalt aluminate (CoAl2O4) has the best nucleating effect. The objective of this work was to determine the influence of the inoculant’s content (cobalt aluminate) in the surface layer of the ceramic mould on the microstructure and mechanical properties at high temperature of nickel based superalloy René 77. For this purpose, the ceramic moulds were made with different concentration of cobalt aluminate in the primary slurry was from 0 to 10% mass. in zirconium flour. Stepped and cylindrical samples were casted for microstructure and mechanical examinations. The average grain size of the matrix ( phase), was determined on the stepped samples. The influence of surface modification on the grain size of up to section thickness was considered. The microstructure investigations with the use of light microscopy and scanning electron microscopy (SEM) enable to examine the influence of the surface modification on the morphology of ’ phase and carbides precipitations. Verification of the influence of CoAl2O4 on the mechanical properties of castings were investigated on the basis of results obtained form creep tests.

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