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1.
STAR Protoc ; 5(2): 103115, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38861381

RESUMO

Manufacturing techniques play an essential role in obtaining optimum mechanical properties of composites. Vacuum-assisted resin infusion (VARI) is a composite fabrication approach for optimal fiber volume fraction. Here, we present a protocol for manufacturing glass fiber-reinforced polymer (GFRP) samples by applying VARI to a modified complex Arcan fixture. We describe steps for material preparation, molding preparation, setting vacuum system, resin mixing, and degassing. We then detail procedures for vacuum infusion process and cutting composites for shear testing samples. For complete details on the use and execution of this protocol, please refer to Alandro et al.1.


Assuntos
Vidro , Vácuo , Vidro/química , Teste de Materiais , Polímeros/química
2.
Polymers (Basel) ; 16(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38674941

RESUMO

Stereolithography has emerged as a recent method in fabricating complex structures with high accuracy. Components using resin have poorer properties. The current study investigates the improvement in the properties of nano-graphite composites fabricated by the SLA technique. The properties are compared for plain resin and 0.2%, 0.5%, 1%, 3%, and 5% (w/v) of nano-graphite mixed with the UV-curable resin. Various analyses were conducted, including viscosity, UV spectroscopy, moisture content, water absorption, gel content, tensile, bending, hardness testing, and microscopic characterization. The results from the experiments showed a difference in the results of each percentage of the specimen tested, such as the specimen property, which shows that the greater the percentage of nano-graphite added (5%), the opaquer the specimen will appear and less light will be reflected. Viscosity testing shows that the greater the percentage of nano-graphite added to the resin, the greater the viscosity. UV spectroscopy testing produced information about the electronic structure and the structure of molecules, such as their composition, purity, and concentration. Observations from the moisture content analysis found that the moisture content in specimens with higher percentages of nano-graphite affected physical and mechanical properties, leading to easier warping, cracking, decreased strength, etc. Tensile and bending testing shows that the greater the percentage of nano-graphite added, the greater the effect on physical and mechanical properties, including fracture. However, certain tests did not consistently yield significant variations among specimens when different percentages of nano-graphite were added, as particularly evident in chemical resistance testing. This study offers valuable insights into the application of nano-graphite composites fabricated via the SLA method.

3.
Data Brief ; 53: 110139, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38357454

RESUMO

This paper presents a dataset of load-displacement obtained from shear loading tests on pure GFRP laminates and hybrid GFRP-graphite filler laminates. The specimens were cut according to the ASTM D 7078 standard, and the width and thickness of the notch area were measured at least three times. Shear loading was applied at a rate of 2 mm/min, and data were recorded from unloading until specimen failure. The data provides information on the maximum load and unique behavior of GFRP laminates. Based on the obtained load, the shear stress (MPa) unit can be calculated. This data can serve as a basis for researchers and engineers working with GFRP laminates and hybrid GFRP-graphite filler laminates.

4.
Polymers (Basel) ; 15(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37299210

RESUMO

Nowadays, the hybridization of natural and glass fiber has promised several advantages as a green composite. Nevertheless, their different characteristics lead to poor mechanical bonding. In this work, agel fiber and glass fiber was used as reinforcements, and activated carbon filler was added to the polymer matrix of a hybrid composite to modify its characteristics and mechanical properties. A tensile and bending test was conducted to evaluate the effect of three different weight percentages of activated carbon filler (1, 2, and 4 wt%). Vacuum-assisted resin infusion was used to manufacture the hybrid composite to obtain the high-quality composite. The results have revealed that adding 1 wt% filler yielded the most optimum result with the highest tensile strength, flexural strength, and elastic modulus, respectively: 112.90 MPa, 85.26 MPa, and 1.80 GPa. A higher weight percentage of activated carbon filler on the composite reduced its mechanical properties. The lowest test value was shown by the composite with 4 wt%. The micrograph observations have proven that the 4 wt% composite formed agglomeration filler that can induce stress concentration and reduce its mechanical performance. Adding 1 wt% filler offered the best dispersion in the matrix, which can enhance better load transfer capability.

5.
Heliyon ; 9(3): e14706, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37101469

RESUMO

The figure eight model was successfully manufactured, analyzed, and characterized in the present study. The model was manufactured via 3D printing fused deposition modelling (FDM) and then reinforced with glass fiber-reinforced polymers (GFRP). There are three different designs in figure eight that are examined, and each design is made using 3D printing FDM and coated with GFRP, a hybrid material, as shown. Specimens that have been made from each design are then evaluated by tensile test, hardness test, surface roughness test, and density test. The results showed that the hybrid figure eight lamination with polylactic acid (PLA) and GFRP material could increase the tensile strength by more than two times higher. The highest tensile strength lies in design 1 with 4977, 3 N. Moreover, the highest hardness value occurred for design two at 75.1 Shore D, and the highest average density lies in design three at 1.2 g/mm3. The study also showed that the lowest cost occurred in hybrid design three at $ 1.2 per item. Based on the present study, the GFRP reinforcement can extend the model's performance with affordable cost and retain figure eight from the failure.

6.
Polymers (Basel) ; 15(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904378

RESUMO

The current study investigates the effect of a hybrid L-profile aluminium/glass-fiber-reinforced polymer stacking sequence under axial and lateral compression loads. Four stacking sequences are studied: aluminium (A)-glass-fiber (GF)-AGF, GFA, GFAGF, and AGFA. In the axial compression test, the aluminium/GFRP hybrid tends to crush in a more progressive and stable failure than the net aluminium and net GFRP specimens, with a relatively more stable load-carrying capacity throughout the experimental tests. The AGF stacking sequence was second, with an energy absorption of 145.31 kJ, following AGFA at 157.19 kJ. The load-carrying capacity of AGFA was the highest, with an average peak crushing force of 24.59 kN. The second-highest peak crushing force, 14.94 kN, was achieved by GFAGF. The highest amount of energy absorption, 157.19 J, was achieved by the AGFA specimen. The lateral compression test showed a significant increase in load-carrying and energy absorption capacity in the aluminium/GFRP hybrid specimens compared to the net GFRP specimens. AGF had the highest energy absorption with 10.41 J, followed by AGFA with 9.49 J. AGF also had the highest peak crushing force with 2.98 kN, followed by AGFA with 2.16 kN. The most crashworthy stacking sequence among the four variations tested in this experimental research was the AGF stacking sequence because of its great load-carrying capacity, energy absorption, and specific energy absorption in axial and lateral loading. The study provides greater insight into the failure of hybrid composite laminates under lateral and axial compression.

7.
Polymers (Basel) ; 14(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36501533

RESUMO

Research on natural-fiber-reinforced polymer composite is continuously developing. Natural fibers from flora have received considerable attention from researchers because their use in biobased composites is safe and sustainable for the environment. Natural fibers that mixed with Carbon Fiber and or Glass Fiber are low-cost, lightweight, and biodegradable and have lower environmental influences than metal-based materials. This study highlights and comprehensively reviews the natural fibers utilized as reinforcements in polyester composites, including jute, bamboo, sisal, kenaf, flax, and banana. The properties of composite materials consisting of natural and synthetic fibers, such as tensile strength, flexural strength, fatigue, and hardness, are investigated in this study. This paper aims to summarize, classify, and collect studies related to the latest composite hybrid science consisting of natural and synthetic fibers and their applications. Furthermore, this paper includes but is not limited to preparation, mechanism, characterization, and evaluation of hybrid composite laminates in different methods and modes. In general, natural fiber composites produce a larger volume of composite, but their strength is weaker than GFRP/CFRP even with the same number of layers. The use of synthetic fibers combined with natural fibers can provide better strength of hybrid composite.

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