Experimental Quantification of the Variability of Mechanical Properties in 3D Printed Continuous Fiber Composites

The material properties of 3D printed continuous fiber composites have been studied many times in the last years. However, only a minimal number of samples were used to determine the properties in each of the reported studies. Moreover, reported results can hardly be compared due to different sample geometries. Consequently, the variability of the mechanical properties (from one sample to the other) is a crucial parameter that has not been well quantified yet. In the present work, the flexural properties of 3D printed continuous carbon fiber/nylon composite specimens were experimentally quantified, using batches of 15 test specimens. In order to account for the possible influence of the quality of the prepreg filaments on the observed variability, three different filament rolls were used to manufacture the different batches. Also, two configurations were tested, with a fiber direction parallel (longitudinal) or perpendicular (transverse) to the main axis of the specimens. The results show moderate to high variabilities of the flexural modulus, flexural strength and maximum strain. The coefficient of variation was more than twice as high in the transverse case as in the longitudinal case.

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The Impact of Slicing Softwares on the Mechanical Properties of 3D Printed Parts

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b3668.079220 ◽

2020 ◽

Vol 9 (2) ◽

pp. 487-494

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

3D Printer ◽

Stl File ◽

3D Printed ◽

Intersection Curves ◽

The Impact

“Slicing tool” or “Slicing Software” computes the intersection curves of models and slicing planes. They improve the quality of the model being printed when given in the form of STL file. Upon analyzing a specimen that has been printed using two different slicing tools, there was a drastic variation on account of the mechanical properties of the specimen. The ultimate tensile strength and the surface roughness of the material vary from one tool to another. This paper reports an investigation and analysis of the variation in the ultimate tensile strength and the surface roughness of the specimen, given that the 3D printer and the model being printed is the same, with a variation of usage of slicing software. This analysis includes ReplicatorG, Flashprint as the two different slicing tools that are used for slicing of the model. The variation in the ultimate tensile strength and the surface roughness are measured and represented statistically through graphs. An appropriate decisive conclusion was drawn on the basis of the observations and analysis of the experiment on relevance to the behavior and mechanical properties of the specimen.

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Mechanical properties and biodegradability of enzyme-retted kenaf fiber composites

Textile Research Journal ◽

10.1177/0040517518779996 ◽

2018 ◽

Vol 89 (9) ◽

pp. 1782-1791 ◽

Cited By ~ 3

Author(s):

Jong Sun Jung ◽

Kyung Hun Song ◽

Seong Hun Kim

Keyword(s):

Mechanical Properties ◽

Adhesion Force ◽

Flexural Modulus ◽

Fiber Composites ◽

Poly Vinyl Alcohol ◽

Modified Starch ◽

Kenaf Fiber ◽

Poly Ethylene ◽

Kenaf Fibers ◽

Aerobic Biodegradability

The mechanical properties and biodegradability of retted kenaf and modified starch composites fabricated by adding enzyme-retted kenaf as a filler and poly(vinyl alcohol) (PVA), poly(ethylene glycol), or glycerol as a plasticizer are compared with those of the NaOH-retted counterparts fabricated under identical conditions. In the case of enzyme retting, the composite treated with the PVA plasticizer was deemed the most appropriate for achieving optimal tensile strength, flexural strength, and flexural modulus. Further, the retting treatment, the length of the kenaf fiber, the type of treatment (single- or double-sided), and the adhesion force at the interface significantly affect the mechanical properties of the composites. According to the aerobic biodegradability assessment in natural reclamation conditions, the modified starch composite fabricated using 50-mm-long enzyme-retted kenaf fibers as the filler and double-side treated with PVA plasticizer showed a biodegradation rate of 80% or higher after 80 days.

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A Facile Method to Fabricate Anisotropic Extracellular Matrix with 3D Printing Topological Microfibers

Materials ◽

10.3390/ma12233944 ◽

2019 ◽

Vol 12 (23) ◽

pp. 3944 ◽

Cited By ~ 1

Author(s):

Zhen Gu ◽

Zili Gao ◽

Wenli Liu ◽

Yongqiang Wen ◽

Qi Gu

Keyword(s):

Mechanical Properties ◽

Extracellular Matrix ◽

Mechanical Characteristics ◽

Fiber Direction ◽

Gelatin Matrix ◽

Simple Method ◽

Elongation At Break ◽

Anisotropic Mechanical Properties ◽

The Matrix ◽

3D Printed

Natural tissues and organs have different requirements regarding the mechanical characteristics of response. It is still a challenge to achieve biomaterials with anisotropic mechanical properties using an extracellular matrix with biological activity. We have improved the ductility and modulus of the gelatin matrix using 3D printed gelatin microfibers with different concentrations and topologies and, at the same, time achieved anisotropic mechanical properties. We successfully printed flat microfibers using partially cross-linked gelatin. We modified the 10% (w/v) gelatin matrix with microfibers consisting of a gelatin concentration of 14% (w/v), increasing the modulus to about three times and the elongation at break by 39% in parallel with the fiber direction. At the same time, it is found that the microfiber topology can effectively change the matrix ductility, and changing the modulus of the gelatin used in the microfiber can effectively change the matrix modulus. These findings provide a simple method for obtaining active biological materials that are closer to a physiological environment.

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A Study of the Effects of Ingredients to the Mechanical Properties of Natural Fiber Composites (NFC)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.689.382 ◽

2013 ◽

Vol 689 ◽

pp. 382-388

Author(s):

Ju Seok Oh ◽

Song Woo Nam ◽

Sun Woong Choi

Keyword(s):

Mechanical Properties ◽

Natural Fiber ◽

Wood Flour ◽

Fiber Composite ◽

Flexural Modulus ◽

Construction Materials ◽

Fiber Composites ◽

Polymer Processing ◽

Base Resin ◽

Natural Fiber Composite

The importance of NFC (Natural Fiber Composite) as construction materials is widely accepted all over the world. But it seems that NFC manufacturers have complicated information about the effect of ingredients to their products. Hence systematic study for optimum composition of NFC is needed. This study is aimed to elucidate the effect of ingredients to the mechanical properties of NFC. We devised design of experiments to draw a firm conclusion. The experiments were conducted with polymer processing machines which are widely accepted in polymer processing industries. The result of ANOVA analysis showed that the most important ingredient of NFC is wood flour. And as the length of wood flour increases, the mechanical properties are enhanced. Contrary to wood flour, base resin has little effect to the mechanical properties of NFC. The effect of coupling agent to flexural modulus is not ignorable, but the effect to flexural strength is different from that of flexural modulus.

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Prediction of Mechanical Properties of Polymer Composites Reinforced with Feather Fibers of ‘Emu’ Bird

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.694 ◽

2014 ◽

Vol 592-594 ◽

pp. 694-699

Author(s):

Chandra V. Sekhar ◽

V. Pandurangadu ◽

T. Subba Rao

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Response Surface Methodology ◽

Natural Fiber ◽

Flexural Modulus ◽

Fiber Composites ◽

Weight Percentage ◽

Feather Fibers ◽

Prediction Of Mechanical Properties ◽

Feather Fiber

Now a day’s researchers are focusing on natural fiber composites. In the present work composites were prepared with epoxy (Araldite LY-556) resin and ‘emu’ bird feathers as fiber. The composites were prepared by varying the weight percentage (P) of ‘emu’ fiber ranging from 1 to 5 and length (L) of feather fibers from 1 to 5 cm. The various mechanical properties like tensile strength, flexural strength; flexural modulus and impact strength were determined. An attempt is made to model the mechanical properties through response surface methodology (RSM). Analysis of Variance (ANOVA) is used to check the validity of the model. The results reveal that the developed models are suitable for prediction of mechanical properties of Epoxy ‘Emu’ Feather Fiber Composites.

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Effect of Process Parameters on Mechanical Properties of 3D Printed Continuous Carbon Fiber Reinforced Composites

Journal of the Japan Society for Composite Materials ◽

10.6089/jscm.45.135 ◽

2019 ◽

Vol 45 (4) ◽

pp. 135-140

Author(s):

Satoshi KOBAYASHI ◽

Wataru YASUNAGA ◽

Toshiko OSADA

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

Process Parameters ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Fiber Reinforced ◽

Carbon Fiber Reinforced Composites ◽

Continuous Carbon Fiber ◽

3D Printed ◽

Carbon Fiber Reinforced

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Effects of the Washing Time and Washing Solution on the Biocompatibility and Mechanical Properties of 3D Printed Dental Resin Materials

Polymers ◽

10.3390/polym13244410 ◽

2021 ◽

Vol 13 (24) ◽

pp. 4410

Author(s):

Na-Kyung Hwangbo ◽

Na-Eun Nam ◽

Jong-Hoon Choi ◽

Jong-Eun Kim

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Cell Viability ◽

Laser Scanning ◽

Flexural Modulus ◽

Three Dimensional ◽

Confocal Laser Scanning ◽

Confocal Laser ◽

3D Printed ◽

Resin Restorations

Three-dimensional (3D) printing technology is highly regarded in the field of dentistry. Three-dimensional printed resin restorations must undergo a washing process to remove residual resin on the surface after they have been manufactured. However, the effect of the use of different washing solutions and washing times on the biocompatibility of the resulting resin restorations is unclear. Therefore, we prepared 3D-printed denture teeth and crown and bridge resin, and then washed them with two washing solutions (isopropyl alcohol and tripropylene glycol monomethyl ether) using different time points (3, 5, 10, 15, 30, 60, and 90 min). After this, the cell viability, cytotoxicity, and status of human gingival fibroblasts were evaluated using confocal laser scanning. We also analyzed the flexural strength, flexural modulus, and surface SEM imaging. Increasing the washing time increased the cell viability and decreased the cytotoxicity (p < 0.001). Confocal laser scanning showed distinct differences in the morphology and number of fibroblasts. Increasing the washing time did not significantly affect the flexural strength and surface, but the flexural modulus of the 90 min washing group was 1.01 ± 0.21 GPa (mean ± standard deviation), which was lower than that of all the other groups and decreased as the washing time increased. This study confirmed that the washing time affected the biocompatibility and mechanical properties of 3D printed dental resins.

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Continuous Fiber Angle Topology Optimization for Polymer Composite Deposition Additive Manufacturing Applications

Fibers ◽

10.3390/fib7020014 ◽

2019 ◽

Vol 7 (2) ◽

pp. 14 ◽

Cited By ~ 9

Author(s):

Delin Jiang ◽

Robert Hoglund ◽

Douglas Smith

Keyword(s):

Mechanical Properties ◽

Topology Optimization ◽

Additive Manufacturing ◽

Carbon Fiber ◽

Polymer Composite ◽

Fiber Reinforcement ◽

Fiber Direction ◽

Optimization Approach ◽

Continuous Fiber ◽

Fiber Angle

Mechanical properties of parts produced with polymer deposition additive manufacturing (AM) depend on the print bead direction, particularly when short carbon-fiber reinforcement is added to the polymer feedstock. This offers a unique opportunity in the design of these structures since the AM print path can potentially be defined in a direction that takes advantage of the enhanced stiffness gained in the bead and, therefore, fiber direction. This paper presents a topology optimization approach for continuous fiber angle optimization (CFAO), which computes the best layout and orientation of fiber reinforcement for AM structures. Statically loaded structures are designed for minimum compliance where the adjoint variable method is used to compute design derivatives, and a sensitivity filter is employed to reduce the checkerboard effect. The nature of the layer-by-layer approach in AM is given special consideration in the algorithm presented. Examples are provided to demonstrate the applicability of the method in both two and three dimensions. The solution to our two dimensional problem is then printed with a fused filament fabrication (FFF) desktop printer using the material distribution results and a simple infill method which approximates the optimal fiber angle results using a contour-parallel deposition strategy. Mechanical stiffness testing of the printed parts shows improved results as compared to structures designed without accounting for the direction of the composite structure. Results show that the mechanical properties of the final FFF carbon fiber/polymer composite printed parts are greatly influenced by the print direction, and optimized material orientation tends to align with the imposed force direction to minimize the compliance.

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