Hybrid Composite Material Reinforced with Carbon Nanolaminates for Gradient Stiffness: Preparation and Characterization

Currently, the procurement of lightweight, tough, and impact resistant materials is garnering significant industrial interest. New hybrid materials can be developed on the basis of the numerous naturally found materials with gradient properties found in nature. However, previous studies on granular materials demonstrate the possibility of capturing the energy generated by an impact within the material itself, thus deconstructing the initial impulse into a series of weaker impulses, dissipating the energy through various mechanisms, and gradually releasing undissipated energy. This work focuses on two production methods: spin coating for creating a granular material with composition and property gradients (an acrylonitrile–butadiene–styrene (ABS) polymer matrix reinforced by carbon nanolaminates at 0.10%, 0.25%, and 0.50%) and 3D printing for generating viscoelastic layers. The aim of this research was to obtain a hybrid material from which better behaviour against shocks and impacts and increased energy dissipation capacity could be expected when the granular material and viscoelastic layers were combined. Nondestructive tests were employed for the morphological characterization of the nanoreinforcement and testing reinforcement homogeneity within the matrix. Furthermore, the Voronoï tessellation method was used as a mathematical method to supplement the results. Finally, mechanical compression tests were performed to reveal additional mechanical properties of the material that had not been specified by the manufacturer of the 3D printing filaments.

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Comparative characteristics of provisional crowns made by CAD/CAM milling and 3D printing

Стоматология для всех ◽

10.35556/idr-2020-2(91)45-49 ◽

2020 ◽

pp. 45-49

Author(s):

A.V. Stomatov ◽

D.V. Stomatov ◽

P.V. Ivanov ◽

V.V. Marchenko ◽

E.V. Piitsky ◽

...

Keyword(s):

3D Printing ◽

Good Alternative ◽

Digital Model ◽

Dental Practice ◽

Production Methods ◽

Automated Production ◽

3D Printing Technology ◽

Cad Cam ◽

Milling Method ◽

Technology Comparison

In this work, the authors studied and compared the two main methods used in dental practice for the automated production of orthopedic structures: the widely used CAD / CAM milling method and the 3D printing technology. As an object of research, temporary crowns were used, which were made on the basis of the same digital model: a) by the method of CAD / CAM milling from polymethylmethacrylate disks; b) by 3D printing from photopolymer resin based on LCD technology. Comparison of production methods and finished designs was carried out according to the following characteristics: strength, durability, aesthetic qualities, accuracy of orthopedic designs, etc. According to the results of the study, it was concluded that 3D printing can be a good alternative to CAD / CAM milling in solving problems of temporary prosthetics.

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Fabrication of Bulk Functionally-Graded Syntactic Foams for Impact Energy Absorption

Materials Science Forum ◽

10.4028/www.scientific.net/msf.706-709.711 ◽

2012 ◽

Vol 706-709 ◽

pp. 711-716 ◽

Cited By ~ 4

Author(s):

Tadaharu Adachi ◽

Masahiro Higuchi

Keyword(s):

Theoretical Analysis ◽

Energy Absorption ◽

Functionally Graded ◽

Fabrication Process ◽

Syntactic Foams ◽

Compression Tests ◽

Matrix Resin ◽

Local Fracture ◽

Density Distributions ◽

The Matrix

Function of functionally-graded (FG) foams as energy absorption material for impact was discussed on the basis of theoretical analysis, and fabrication process of the foams was proposed in the paper. The FG foams were found to be useful as impact absorber due to progressively local fracture or cushion in the theoretical analysis. Next the fabrication process of the FG foams was suggested. The graded dispersion of the micro-balloons was conducted before curing the matrix resin in the process. The density distributions in the FG foams were confirmed to be predicted by the numerical analysis on the basis of floating the micro-balloons. Finally, compression tests were carried out to evaluate mechanical properties.

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The Effects of Hydrothermal Ageing on the Crushing Behavior of Glass/Epoxy Composite Pipes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.819.411 ◽

2015 ◽

Vol 819 ◽

pp. 411-416

Author(s):

S.N. Fitriah ◽

M.S. Abdul Majid ◽

R. Daud ◽

M. Afendi ◽

Z.S. Nazirah

Keyword(s):

Composite Laminates ◽

Testing Machine ◽

Hydrothermal Condition ◽

Compression Tests ◽

Universal Testing ◽

Failure Region ◽

The Matrix ◽

Glass Fibre Reinforced ◽

Crushing Behavior ◽

Composite Pipes

The paper discusses the crushing behavior of glass fibre reinforced epoxy (GRE) pipes under hydrothermal ageing condition. This study determines the behavior of the GRE pipes when subjected to different ageing periods and temperatures. Hydrothermal ageing has been found to cause degradation between resin and fibre interface thus causing the reduction in the strength of composite laminates. The pipes were subjected to hydrothermal condition to simulate and precipitate ageing by immersing the pipe samples in water at 80°C for 250, 500, and 1000 hours. Compression tests were carried out using Universal Testing Machine (UTM) for virgin condition and aged samples in accordance with ASTM D695 standard. The maximum force at the initial failure region is observed for each of the conditioned pipes. The results show that the strength of the matrix systems was considerably degraded due to the plasticization of the matrix system.

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Hot Deformation Behavior of a Ni-Based Superalloy with Suppressed Precipitation

Metals ◽

10.3390/met11040605 ◽

2021 ◽

Vol 11 (4) ◽

pp. 605

Author(s):

Franco Lizzi ◽

Kashyap Pradeep ◽

Aleksandar Stanojevic ◽

Silvana Sommadossi ◽

Maria Cecilia Poletti

Keyword(s):

Dynamic Recrystallization ◽

Strain Rate ◽

Hot Deformation ◽

Strain Rates ◽

Compression Tests ◽

Deformation Bands ◽

Stress Softening ◽

Relative Stress ◽

The Matrix ◽

Thermomechanical Processes

Inconel®718 is a well-known nickel-based super-alloy used for high-temperature applications after thermomechanical processes followed by heat treatments. This work describes the evolution of the microstructure and the stresses during hot deformation of a prototype alloy named IN718WP produced by powder metallurgy with similar chemical composition to the matrix of Inconel®718. Compression tests were performed by the thermomechanical simulator Gleeble®3800 in a temperature range from 900 to 1025 °C, and strain rates scaled from 0.001 to 10 s−1. Flow curves of IN718WP showed similar features to those of Inconel®718. The relative stress softening of the IN718WP was comparable to standard alloy Inconel®718 for the highest strain rates. Large stress softening at low strain rates may be related to two phenomena: the fast recrystallization rate, and the coarsening of micropores driven by diffusion. Dynamic recrystallization grade and grain size were quantified using metallography. The recrystallization grade increased as the strain rate decreased, although showed less dependency on the temperature. Dynamic recrystallization occurred after the formation of deformation bands at strain rates above 0.1 s−1 and after the formation of subgrains when deforming at low strain rates. Recrystallized grains had a large number of sigma 3 boundaries, and their percentage increased with strain rate and temperature. The calculated apparent activation energy and strain rate exponent value were similar to those found for Inconel®718 when deforming above the solvus temperature.

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Influence of Part Orientation on the Surface Roughness in the Process of Fused Deposition Modeling

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.896.29 ◽

2021 ◽

Vol 896 ◽

pp. 29-37

Author(s):

Ján Milde ◽

František Jurina ◽

Jozef Peterka ◽

Patrik Dobrovszký ◽

Jakub Hrbál ◽

...

Keyword(s):

Surface Roughness ◽

3D Printing ◽

Fused Deposition Modeling ◽

Orientation Angle ◽

Acrylonitrile Butadiene Styrene ◽

Lower Surface ◽

Geometrical Model ◽

Fused Deposition ◽

Deposition Modeling ◽

Part Orientation

The article focused on the influence of part orientation on the surface roughness of cuboid parts during the process of fabricating by FDM technology. The components, in this case, is simple cuboid part with the dimensions 15 mm x 15mm x 30 mm. A geometrical model is defined that considers the shape of the material filaments after deposition, to define a theoretical roughness profile, for a certain print orientation angle. Five different print orientations in the X-axis of the cuboid part were set: 0°, 30°, 45°, 60°, and 90°. According to previous research in the field of FDM technology by the author, the internal structure (infill) was set at the value of 70%. The method of 3D printing was the Fused Deposition Modeling (FDM) and the material used in this research was thermoplastic ABS (Acrylonitrile butadiene styrene). For each setting, there were five specimens (twenty five prints in total). Prints were fabricated on a Zortrax M200 3D printer. After the 3D printing, the surface “A” was investigated by portable surface roughness tester Mitutoyo SJ-210. Surface roughness in the article is shown in the form of graphs (Fig.7). Results show increase in part roughness with increasing degree of part orientation. When the direction of applied layers on the measured surface was horizontal, significant improvement in surface roughness was observed. Findings in this paper can be taken into consideration when designing parts, as they can contribute in achieving lower surface roughness values.

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Thermal, structural, and mechanical effects of nanofibrillated cellulose in polylactic acid filaments for additive manufacturing

BioResources ◽

10.15376/biores.15.4.7954-7964 ◽

2020 ◽

Vol 15 (4) ◽

pp. 7954-7964

Author(s):

Diego Gomez-Maldonado ◽

Maria Soledad Peresin ◽

Christina Verdi ◽

Guillermo Velarde ◽

Daniel Saloni

Keyword(s):

Tensile Strength ◽

Additive Manufacturing ◽

3D Printing ◽

Polylactic Acid ◽

Modulus Of Elasticity ◽

Manufacturing Process ◽

Thermal Characterization ◽

Nanofibrillated Cellulose ◽

Small Decrease ◽

The Matrix

As the additive manufacturing process gains worldwide importance, the need for bio-based materials, especially for in-home polymeric use, also increases. This work aims to develop a composite of polylactic acid (PLA) and nanofibrillated cellulose (NFC) as a sustainable approach to reinforce the currently commercially available PLA. The studied materials were composites with 5 and 10% NFC that were blended and extruded. Mechanical, structural, and thermal characterization was made before its use for 3D printing. It was found that the inclusion of 10% NFC increased the modulus of elasticity in the filaments from 2.92 to 3.36 GPa. However, a small decrease in tensile strength was observed from 55.7 to 50.8 MPa, which was possibly due to the formation of NFC aggregates in the matrix. This work shows the potential of using PLA mixed with NFC for additive manufacturing.

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Electromechanical Assessment and Induced Temperature Measurement of Carbon Fiber Tows under Tensile Condition

Materials ◽

10.3390/ma13194234 ◽

2020 ◽

Vol 13 (19) ◽

pp. 4234

Author(s):

Samir Mekid ◽

Hammam Daraghma ◽

Salem Bashmal

Keyword(s):

Carbon Fiber ◽

3D Printing ◽

Tensile Test ◽

Thermal Characteristics ◽

Acrylonitrile Butadiene Styrene ◽

Break Point ◽

Host Material ◽

Special Focus ◽

Host Materials ◽

Butadiene Styrene

The paper presents an investigation and analysis of the electromechanical and thermal characteristics of the carbon fiber alone as single tow and embedded in host materials such as polymer e.g., acrylonitrile butadiene styrene (ABS) using 3D printing. While carbon fibers can partially reinforce the structure, they can act as sensors to monitor the structural health of the host material. The piezo-resistive behavior was examined without any pretreatment of the carbon fiber under tensile test in both cases. Special focus on the filaments clamping types and their effects was observed. An auxetic behavior was exhibited; otherwise, the free part shows elastic and yielding ranges with break point at high resistance. An induced temperature of the carbon fiber was measured during the tensile test to show low variation. The carbon fiber can provide strength contribution to the host material depending on the percentage of filling the material in 3D printing. The relative variation of the electrical resistance increases by 400% while embedded in the host material, but decreases as the tows filament density increases from 1 to 12 K.

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Method for the Microstructural Characterisation of Unidirectional Composite Tapes

Journal of Composites Science ◽

10.3390/jcs5100275 ◽

2021 ◽

Vol 5 (10) ◽

pp. 275

Author(s):

Nico Katuin ◽

Daniël M. J. Peeters ◽

Clemens A. Dransfeld

Keyword(s):

Voronoi Tessellation ◽

Unidirectional Composite ◽

Fibre Volume ◽

Cross Sectional ◽

Reinforced Polymer ◽

Novel Approach ◽

The Matrix ◽

Carbon Fibre Reinforced Polymer ◽

Fibre Reinforced Polymer ◽

Microstructural Characterisation

The outstanding properties of carbon fibre-reinforced polymer composites are affected by the development of its microstructure during processing. This work presents a novel approach to identify microstructural features both along the tape thickness and through the thickness. Voronoi tessellation-based evaluation of the fibre volume content on cross-sectional micrographs, with consideration of the matrix boundary, is performed. The method is shown to be robust and is suitable to be automated. It has the potential to discriminate specific microstructural features and to relate them to processing behaviour removing the need for manufacturing trials.

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Development of 3D Printed Symbrachydactyly Prosthetic Hand

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a3032.109119 ◽

2019 ◽

Vol 9 (1) ◽

pp. 5943-5947

Keyword(s):

3D Printing ◽

Minimum Cost ◽

Acrylonitrile Butadiene Styrene ◽

Design Stage ◽

Patient Specific ◽

Prosthetic Hand ◽

Simple Task ◽

3D Printed ◽

Electrical Component ◽

Hand Geometry

Symbrachydactyly is a genetical problem occurred to newborn where the newborn experienced underdeveloped or shorten fingers. This condition will limit their normal as even a simple task of holding an item or pushing a button. A device is needed to help them gain a better life. The aim of this project is to fabricate a customized prosthesis hand using 3D printing technology at minimum cost. The proposed prosthetic was not embedded with any electrical component. The patient can only use the wrist to control the prosthetic part which is the prosthetic fingers. The prosthetic hand was also being developed with the patient specific features, which the initial design stage was adapted from a person’s hand geometry using a 3D scanner. Next the model of the prosthesis was analyzed computationally to predict the performance of the product. Different material properties are considered in the analysis to present Polylactic Acid (PLA) and Acrylonitrile Butadiene Styrene (ABS) materials. Then, the prosthesis was fabricated using the 3D printing. The results suggested that PLA material indicated better findings and further be fabricated.

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Detailed Thermal Characterization of Acrylonitrile Butadiene Styrene and Polylactic Acid Based Carbon Composites Used in Additive Manufacturing

Polymers ◽

10.3390/polym12122960 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2960

Author(s):

Zoltan Ujfalusi ◽

Attila Pentek ◽

Roland Told ◽

Adam Schiffer ◽

Miklos Nyitrai ◽

...

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Thermal Hysteresis ◽

Acrylonitrile Butadiene Styrene ◽

Thermal Characterization ◽

Carbon Composites ◽

Biomedical Sensors ◽

Temperature Range ◽

Ohmic Resistance ◽

Significant Difference

Currently, 3D printing is an affordable technology for industry, healthcare, and individuals. Understanding the mechanical properties and thermoplastic behaviour of the composites is critical for the users. Our results give guidance for certain target groups including professionals in the field of additive manufacturing for biomedical components with in-depth characterisation of the examined commercially available ABS and PLA carbon-based composites. The study aimed to characterize these materials in terms of thermal behaviour and structure. The result of the heating-cooling loops is the thermal hysteresis effect of Ohmic resistance with its accommodation property in the temperature range of 20–84 °C for ESD-ABS and 20–72 °C for ESD-PLA. DSC-TGA measurements showed that the carbon content of the examined ESD samples is ~10–20% (m/m) and there is no significant difference in the thermodynamic behaviour of the basic ABS/PLA samples and their ESD compounds within the temperature range typically used for 3D printing. The results support the detailed design process of 3D-printed electrical components and prove that ABS and PLA carbon composites are suitable for prototyping and the production of biomedical sensors.

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