scholarly journals Additive Manufacturing and Characterization of Metal Particulate Reinforced Polylactic Acid (PLA) Polymer Composites

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3545
Author(s):  
Ved S. Vakharia ◽  
Lily Kuentz ◽  
Anton Salem ◽  
Michael C. Halbig ◽  
Jonathan A. Salem ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Additive Manufacturing ◽  
Polylactic Acid ◽  
Mechanical Response ◽  
Cross Sectional ◽  
Reinforced Polymers ◽  
Tensile Response ◽  
Before And After ◽  
Polymer Microstructures

Affordable commercial desktop 3-D printers and filaments have introduced additive manufacturing to all disciplines of science and engineering. With rapid innovations in 3-D printing technology and new filament materials, material vendors are offering specialty multifunctional metal-reinforced polymers with unique properties. Studies are necessary to understand the effects of filament composition, metal reinforcements, and print parameters on microstructure and mechanical behavior. In this study, densities, metal vol%, metal cross-sectional area %, and microstructure of various metal-reinforced Polylactic Acid (PLA) filaments were characterized by multiple methods. Comparisons are made between polymer microstructures before and after printing, and the effect of printing on the metal-polymer interface adhesion has been demonstrated. Tensile response and fracture toughness as a function of metal vol% and print height was determined. Tensile and fracture toughness tests show that PLA filaments containing approximately 36 vol% of bronze or copper particles significantly reduce mechanical properties. The mechanical response of PLA with 12 and 18 vol% of magnetic iron and stainless steel particles, respectively, is similar to that of pure PLA with a slight decrease in ultimate tensile strength and fracture toughness. These results show the potential for tailoring the concentration of metal reinforcements to provide multi-functionality without sacrificing mechanical properties.

scholarly journals Additive manufacturing of PLA-based scaffolds intended for bone regeneration and strategies to improve their biological properties

e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 571-599
Author(s):  
Ricardo Donate ◽  
Mario Monzón ◽  
María Elena Alemán-Domínguez
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Additive Manufacturing ◽  
Bone Regeneration ◽  
Polylactic Acid ◽  
State Of The Art ◽  
Biological Properties ◽  
Design Stage ◽  
Bone Scaffolds ◽  
Regeneration Of Bone

AbstractPolylactic acid (PLA) is one of the most commonly used materials in the biomedical sector because of its processability, mechanical properties and biocompatibility. Among the different techniques that are feasible to process this biomaterial, additive manufacturing (AM) has gained attention recently, as it provides the possibility of tuning the design of the structures. This flexibility in the design stage allows the customization of the parts in order to optimize their use in the tissue engineering field. In the recent years, the application of PLA for the manufacture of bone scaffolds has been especially relevant, since numerous studies have proven the potential of this biomaterial for bone regeneration. This review contains a description of the specific requirements in the regeneration of bone and how the state of the art have tried to address them with different strategies to develop PLA-based scaffolds by AM techniques and with improved biofunctionality.

scholarly journals Suitability of Recycled PLA Filament Application in Fused Filament Fabrication Process

2021 ◽  
Vol 15 (4) ◽  
pp. 491-497
Author(s):  
Tomislav Breški ◽  
Lukas Hentschel ◽  
Damir Godec ◽  
Ivica Đuretek
Keyword(s):  
Mechanical Properties ◽  
Additive Manufacturing ◽  
Polylactic Acid ◽  
Design Of Experiment ◽  
Experimental Approach ◽  
Manufacturing Processes ◽  
Support Structures ◽  
Fused Filament Fabrication ◽  
Layer Height ◽  
Printing Parameters

Fused filament fabrication (FFF) is currently one of the most popular additive manufacturing processes due to its simplicity and low running and material costs. Support structures, which are necessary for overhanging surfaces during production, in most cases need to be manually removed and as such, they become waste material. In this paper, experimental approach is utilised in order to assess suitability of recycling support structures into recycled filament for FFF process. Mechanical properties of standardized specimens made from recycled polylactic acid (PLA) filament as well as influence of layer height and infill density on those properties were investigated. Optimal printing parameters for recycled PLA filaments are determined with Design of Experiment methods (DOE).

Microstructure and Mechanical Properties of TiB2/ Al-Si Composites Fabricated by TIG Wire and Arc Additive Manufacturing

2019 ◽  
Vol 944 ◽  
pp. 64-72
Author(s):  
Qing Feng Yang ◽  
Cun Juan Xia ◽  
Ya Qi Deng
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Additive Manufacturing ◽  
Yield Strength ◽  
Filler Wire ◽  
T6 Heat Treatment ◽  
Microstructure And Mechanical Properties ◽  
Before And After

Bulky sample was made by using TIG wire and arc additive manufacturing (WAAM) technology, in which Ф1.6 mm filler wire of in-situ TiB2/Al-Si composites was selected as deposition metal, following by T6 heat treatment. The microstructure and mechanical properties of the bulky sample before and after heat treatment were analyzed. Experimental results showed that the texture of the original samples parallel to the weld direction and perpendicular to the weld direction was similar consisting of columnar dendrites and equiaxed crystals. After T6 heat treatment, the hardness of the sample was increased to 115.85 HV from 62.83 HV, the yield strength of the sample was 273.33 MPa, the average tensile strength was 347.33 MPa, and the average elongation after fracture was 7.96%. Although pore defects existed in the fracture, yet the fracture of the sample was ductile fracture.

Mechanical properties of fiber reinforced polymer composites: A comparative study of conventional and additive manufacturing methods

2018 ◽  
Vol 52 (23) ◽  
pp. 3173-3181 ◽  
Author(s):  
Kuldeep Agarwal ◽  
Suresh K Kuchipudi ◽  
Benoit Girard ◽  
Matthew Houser
Keyword(s):  
Mechanical Properties ◽  
Additive Manufacturing ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced Polymers ◽  
Manufacturing Processes ◽  
Fiber Reinforced ◽  
Reinforced Polymers ◽  
Reinforced Polymer ◽  
Fiber Reinforced Polymer Composites ◽  
Composite Filament

Fiber reinforced polymer composites have been around for many decades but recently their use has started to increase in multiple industries such as automotive, aerospace, and construction. The conventional composite manufacturing processes such as wet lay-up, resin transfer molding, automatic lay ups etc. suffer from a lot of practical and material issues which have limited their use. The mechanical properties of the parts produced by such processes also suffer from variation that causes problems downstream. Composites based additive manufacturing processes such as Fused Deposition Modeling and Composite Filament Fabrication are trying to remove some of the barriers to the use of composites. Additive manufacturing processes offer more design and material freedom than conventional composite manufacturing processes. This paper compares conventional composite processes for the manufacturing of Epoxy-Fiberglass fiber reinforced polymers with composite filament fabrication based Nylon-Fiberglass fiber reinforced polymers. Mechanical properties such as tensile strength, elastic modulus, and fatigue life are compared for the different processes. The effect of process parameters on these mechanical properties for the composite filament fabrication based process is also examined in this work. It is found that the composite filament fabrication based process is very versatile and the parts manufactured by this process can be used in various applications.

scholarly journals Investigation of a Short Carbon Fibre-Reinforced Polyamide and Comparison of Two Manufacturing Processes: Fused Deposition Modelling (FDM) and Polymer Injection Moulding (PIM)

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 672 ◽  
Author(s):  
Elena Verdejo de Toro ◽  
Juana Coello Sobrino ◽  
Alberto Martínez Martínez ◽  
Valentín Miguel Eguía ◽  
Jorge Ayllón Pérez
Keyword(s):  
Mechanical Properties ◽  
Additive Manufacturing ◽  
3D Printing ◽  
Injection Moulding ◽  
New Technologies ◽  
Mechanical Response ◽  
Fused Deposition Modelling ◽  
Layer By Layer ◽  
Polymer Injection ◽  
Fused Deposition

New technologies are offering progressively more effective alternatives to traditional ones. Additive Manufacturing (AM) is gaining importance in fields related to design, manufacturing, engineering and medicine, especially in applications which require complex geometries. Fused Deposition Modelling (FDM) is framed within AM as a technology in which, due to their layer-by-layer deposition, thermoplastic polymers are used for manufacturing parts with a high degree of accuracy and minimum material waste during the process. The traditional technology corresponding to FDM is Polymer Injection Moulding, in which polymeric pellets are injected by pressure into a mould using the required geometry. The increasing use of PA6 in Additive Manufacturing makes it necessary to study the possibility of replacing certain parts manufactured by injection moulding with those created using FDM. In this work, PA6 was selected due to its higher mechanical properties in comparison with PA12. Moreover, its higher melting point has been a limitation for 3D printing technology, and a further study of composites made of PA6 using 3D printing processes is needed. Nevertheless, analysis of the mechanical response of standardised samples and the influence of the manufacturing process on the polyamide’s mechanical properties needs to be carried out. In this work, a comparative study between the two processes was conducted, and conclusions were drawn from an engineering perspective.

scholarly journals Numerical Study on the Temperature-Dependent Viscosity Effect on the Strand Shape in Extrusion-Based Additive Manufacturing

2020 ◽  
Vol 4 (2) ◽  
pp. 46 ◽  
Author(s):  
Behrouz Behdani ◽  
Matthew Senter ◽  
Leah Mason ◽  
Ming Leu ◽  
Joontaek Park
Keyword(s):  
Experimental Data ◽  
Additive Manufacturing ◽  
Polylactic Acid ◽  
Extrusion Process ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Temperature Dependent ◽  
Temperature Dependent Viscosity ◽  
Cross Sectional ◽  
Dependent Viscosity

A numerical model that incorporates temperature-dependent non-Newtonian viscosity was developed to simulate the extrusion process in extrusion-based additive manufacturing. Agreement with the experimental data was achieved by simulating a polylactic acid melt flow as a non-isothermal power law fluid using experimentally fitted parameters for polylactic acid. The model was used to investigate the temperature effect on the flow behavior, the cross-sectional area, and the uniformity of the extruded strand. OpenFOAM, an open source simulation tool based on the finite volume method, was used to perform the simulations. A computational module for solving the equations of non-isothermal multiphase flows was also developed to simulate the extrusion process under a small gap condition where the gap between the nozzle and the substrate surface is smaller than the nozzle diameter. Comparison of the strand shapes obtained from our model with isothermal Newtonian simulation, and experimental data confirms that our model improves the agreement with the experimental data. The result shows that the cross-sectional area of the extruded strand is sensitive to the temperature-dependent viscosity, especially in the small gap condition which has recently increased in popularity. Our numerical investigation was able to show nozzle temperature effects on the strand shape and surface topography which previously had been investigated and observed empirically only.

Mechanical Properties of Zirconia/Alumina Nano-Composite after Soaking in Various Water-Based Conditions

2006 ◽  
Vol 309-311 ◽  
pp. 1219-1222 ◽  
Author(s):  
Seiji Ban ◽  
Masahiro Nawa ◽  
Y. Suehiro ◽  
H. Nakanishi
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Tetragonal Zirconia ◽  
Flexure Strength ◽  
Nano Composite ◽  
Dental Restorations ◽  
Dental Restoratives ◽  
All Ceramic ◽  
Water Based ◽  
Before And After

Yttria stabilized tetragonal zirconia polycrystals (Y-TZP) have been applied to dental crown and bridges. Whereas, to further improve its mechanical strength, the zirconia/alumina nano-composite stabilized with cerium oxide (Ce-TZP/Al2O3 nano-composite) was developed. In the present study, biaxial flexure strength, fracture toughness and hardness were determined before and after soaking in water-based conditions and the possibility of application to all ceramic dental restorations was discussed. In comparison to Y-TZP, Ce-TZP/Al2O3 nano-composite has quite high flexure strength and fracture toughness along with satisfied durability for LTAD in various water-based conditions encountered in dentistry. Therefore, it is concluded that the nano-composite can be safely applied to dental restoratives such as all-ceramic bridges.

Characterization of Structure and Mechanical Properties of MoSi2-SiC Nanolayer Composites

1993 ◽  
Vol 322 ◽  
Author(s):  
H. Kung ◽  
T. R. Jervis ◽  
J-P. Hirvonen ◽  
M. Nastasi ◽  
T. E. Mitchell
Keyword(s):  
Mechanical Properties ◽  
Structural Changes ◽  
Crystallization Process ◽  
Mechanical Response ◽  
Cross Sectional ◽  
Annealing Conditions ◽  
Transmission Electron ◽  
Layer Structures ◽  
Amorphous Structures

AbstractA systematic study of the structure-mechanical properties relationship is reported for MoSi2-SiC nanolayer composites. Alternating layers of MoSi2 and SiC were synthesized by DCmagnetron and if-diode sputtering, respectively. Cross-sectional transmission electron microscopy was used to examine three distinct reactions in the specimens when exposed to different annealing conditions: crystallization and phase transformation of MoSi2, crystallization of SiC, and spheroidization of the layer structures. Nanoindentation was employed to characterize the mechanical response as a function of the structural changes. As-sputtered material exhibits amorphous structures in both types of layers and has a hardness of 11GPa and a modulus of 217GPa. Subsequent heat treatment induces crystallization of MoSi2 to form the C40 structure at 500°C and SiC to form the a structure at 700°C. The crystallization process is directly responsible for the hardness and modulus increase in the multilayers. A hardness of 24GPa and a modulus of 340GPa can be achieved through crystallizing both MoSi2 and SiC layers. Annealing at 900°C for 2h causes the transformation of MoSi2 into the Cllb structure, as well as spheroidization of the layering to form a nanocrystalline equiaxed microstructure. A slight degradation in hardness but not in modulus is observed accompanying the layer break-down.

scholarly journals Effect of Porosity and Crystallinity on 3D Printed PLA Properties

Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1487 ◽  
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.

Mechanical Properties of Polylactic Acid and Natural Rubber Blends Using Vetiver Grass Fiber as Filler

2010 ◽  
Vol 123-125 ◽  
pp. 1167-1170 ◽  
Author(s):  
Punmanee Juntuek ◽  
Chaiwat Ruksakulpiwat ◽  
Pranee Chumsamrong ◽  
Yupaporn Ruksakulpiwat
Keyword(s):  
Mechanical Properties ◽  
Injection Molding ◽  
Natural Rubber ◽  
Polylactic Acid ◽  
Compression Molding ◽  
Molecular Weight Determination ◽  
Vetiver Grass ◽  
Rubber Blends ◽  
Before And After ◽  
Internal Mixer

Polylactic acid (PLA) and natural rubber (NR) were melt blended with vetiver grass fiber using an internal mixer. Heat treatment at the temperature of 180°C was done to obtain heat treated vetiver grass fiber. Glycidyl methacrylate grafted natural rubber (NR-g-GMA) was used as a compatibilizer of PLA/vetiver/NR composites. The injection molding and compression molding were used to prepare the specimens. Molecular weight determination of PLA before and after processing was done by Gel Permeable Chromatography (GPC).Comparisons between the mechanical properties of the composites prepared from injection molding and compression molding were made.

Sign in / Sign up

Export Citation Format

Share Document