Thermal and mechanical fatigue of a PA66/glass fibers composite material

Multifunctional composite materials are highly sought-after by the aerospace and aeronautical industry but their performance depends on their ability to sustain various forms of damages, in particular damages due to repeated impacts. In this work we studied the mechanical behavior of a layered glass-epoxy composite with copper inserts subjected to fatigue under repeated impacts with different energy levels. Damage evolution as a function of impact energy was carefully monitored in order to determine the effect of the copper inserts on mechanical characteristics of the multifunctional composite, such as endurance and life. Results of repeated impact tests show that electric current interruption in the copper inserts occurs prior to the total perforation of the composite material, and after about 75% of the total number of impacts to failure. This is the case for the three energy levels considered in this study, [Formula: see text] = 2, 3 and 4 Joules. The epoxy resin was dissolved chemically in order to preserve the mechanical structure of the damaged copper inserts and the composite fibers for further inspection and analysis. Scanning electron microscopy (SEM) of the fractured copper inserts revealed interesting information on the nature of the damage, including information on plastic deformation, strain hardening, cracking mode, temperature increase during the impacts, and most importantly the glass fibers and their roles during the impact-fatigue tests.

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Polyurethane derived from castor oil reinforced with long cotton fibers: Static and dynamic testing of a novel eco-friendly composite material

Journal of Composite Materials ◽

10.1177/0021998320911984 ◽

2020 ◽

Vol 54 (22) ◽

pp. 3125-3142

Author(s):

Romeu RC da Costa ◽

Eduardo S Sato ◽

Marcelo L Ribeiro ◽

Ricardo de Medeiros ◽

André FC Vieira ◽

...

Keyword(s):

Composite Material ◽

Castor Oil ◽

Failure Modes ◽

Mechanical Performance ◽

Volume Fraction ◽

Glass Fibers ◽

Natural Fibers ◽

Dynamic Responses ◽

Cotton Fibers ◽

The Novel

A novel eco-friendly composite material made of polyurethane derived from castor oil reinforced with long cotton fibers was developed. A set of comparative analyses comprising static and dynamic tests was established using specimens made of castor oil-based polyurethane reinforced by glass fibers, and epoxy reinforced by glass and cotton fibers. The manufacturing method and estimation of fiber volume fraction of the specimens were described in detail. Tensile and flexural tests were performed to evaluate the mechanical performance of the novel laminate. Fractographic post-mortem examinations assessed the quality of the fiber–matrix interaction and allowed direct observation of the failure modes. Surface treatment of natural fibers appears necessary to improve the adhesion of the natural fibers to the matrix. Dynamic responses are discussed, considering natural frequencies and modal damping coefficients. In this context, the potentialities and the limitations of using the novel eco-friendly composite material as structural parts are discussed.

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EFFECTS OF STRAIN RATE AND TEMPERATURE ON THE MECHANICAL PROPERTIES OF GFRP COMPOSITES

Revista de Engenharia Térmica ◽

10.5380/reterm.v10i1-2.61945 ◽

2011 ◽

Vol 10 (1-2) ◽

pp. 03 ◽

Cited By ~ 1

Author(s):

J. L. V. Coelho ◽

J. M. L. Reis

Keyword(s):

Mechanical Properties ◽

Composite Material ◽

Strain Rate ◽

Elevated Temperatures ◽

Mechanical Response ◽

Polymer Matrix Composites ◽

Glass Fibers ◽

Research Data ◽

Matrix Composites ◽

Gfrp Composites

In this work, the mechanical response of a composite material based on glass fibers embedded in an epoxy resin was experimentally studied as a function of strain rate and temperature. It was shown that for the temperature range from 23 to 100 °C the elastic properties of the composite are significant affected and the strain rate influences only the ultimate strength. The experimental research data and the approaches presented in this work should significantly extend our knowledge of the effect of elevated temperatures on the mechanical behavior of high temperature polymer matrix composites.

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Lime-Based Mortar Reinforced by Randomly Oriented Short Fibers for the Retrofitting of the Historical Masonry Structure

Materials ◽

10.3390/ma13163462 ◽

2020 ◽

Vol 13 (16) ◽

pp. 3462 ◽

Cited By ~ 3

Author(s):

Michele Angiolilli ◽

Amedeo Gregori ◽

Marco Vailati

Keyword(s):

Composite Material ◽

Glass Fibers ◽

Testing Machine ◽

Fiber Reinforced Polymers ◽

Fiber Reinforced ◽

Short Fibers ◽

Promising Alternative ◽

Historic Masonry ◽

Masonry Construction ◽

Aspect Ratios

Recent seismic events prompted research to develop innovative materials for strengthening and repair of both modern and historic masonry constructions (buildings, bridges, towers) and structural components (walls, arches and vaults, pillars, and columns). Strengthening solutions based on composite materials, such as the Fiber Reinforced Polymers (FRP) or the Fiber Reinforced Cementitious Matrix (FRCM), have been increasingly considered in the last two decades. Despite reinforcement made of short-fibers being a topic that has been studied for several years from different researchers, it is not yet fully considered for the restoration of the masonry construction. This work aims to experimentally investigate the enhancement of the mechanical properties of lime-based mortar reinforced by introducing short glass fibers in the mortar matrix with several contents and aspect ratios. Beams with dimensions of 160 mm × 40 mm × 40 mm with a central notch were tested in three-point bending configuration aiming to evaluate both the flexural strength and energy fracture of the composite material. Then, the end pieces of the broken beams were tested in Brazilian and compressive tests. All the tests were performed by a hydraulic displacement-controlled testing machine. Results highlight that the new composite material ensures excellent ductility capacity and it can be considered a promising alternative to the classic fiber-reinforcing systems.

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Static and fatigue behaviors of short glass fiber–reinforced polypropylene composites aged in a wet environment

Journal of Composite Materials ◽

10.1177/0021998319861142 ◽

2019 ◽

Vol 53 (25) ◽

pp. 3629-3647 ◽

Cited By ~ 2

Author(s):

Lilla Mansouri ◽

Arezki Djebbar ◽

Samir Khatir ◽

Hafiz Tauqeer Ali ◽

Amar Behtani ◽

...

Keyword(s):

Composite Material ◽

Glass Fibers ◽

Fatigue Loading ◽

Fatigue Tests ◽

Distilled Water ◽

Static Tests ◽

Polypropylene Composites ◽

Injection Process ◽

Test Criteria ◽

Short Glass

In this paper, a new experimental study of the bending static and fatigue behaviors of a composite material reinforced with 40% by mass of short glass fibers (type E) and polypropylene matrix is presented. The composite material is obtained in the form of plates by an injection process, which inevitably affects the distribution of the fibers and therefore the behavior of the material studied. To do this, several techniques are implemented on specimens by cutting them in transverse and longitudinal directions. The effect of aging in distilled water at 40℃ on the mechanical characteristics is studied under static and fatigue loading conditions. The static tests, three-point flexure up to failure, allow us to choose the levels of stress for the fatigue tests. The endurance curves as a function of the number of cycles are plotted by adapting the end-of-test criteria N5, N10, and N20, which represent a rigidity drop of 5%, 10%, and 20%, respectively. An interpretation of the Wöhler curve equations defined for the end-of-test criteria allows defining the kinetics of material damage. The results highlighted the influence of distilled water on the mechanical behavior and the lifetime of the material. We also perform macroscopic observations of fracture and microscopic facies in order to identify the damage mechanisms of the composite material.

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DESIGN FABRICATION AND CAMPARATIVE ANALYSIS OF INDUSTRIAL SAFETY HELMET USING GLASS FIBERS REINFORCED WITH EPOXY RESIN

10.31224/osf.io/jgfup ◽

2020 ◽

Author(s):

M. Balakrishna ◽

D. Sandeep ◽

G. Sanjay ◽

K. Jogiraju ◽

P. Sateesh

Keyword(s):

Power Generation ◽

Finite Element Analysis ◽

Finite Element ◽

Composite Material ◽

Occupational Health ◽

Epoxy Resin ◽

Glass Fibers ◽

Industrial Safety ◽

Element Analysis ◽

Component Testing

Now-a-days, safety is very important in various on-site industries likemanufacturing, construction & power generation industries. To escape the workerfrom head damage, wearing of industrial safety helmet in on-site industries hasbecome obligatory according to OHSAS 18001[Occupational Health and SafetyAssessment Series]. Hence the resisting possessions of safety helmet should be high tohold out against the fortuitous circumstances. This project focuses on scrutinizing andcomparing the fabricated industrial safety helmet using composite material which ismake by us, with existing industrial safety helmet. The fabricated safety helmet shallbe figure out in both practically and theoretically processes. In practical examiningthe fabricated helmet shall go through the component testing which was specified byBIS 2925 [Bureau of Indian Standards]. In theoretical the results of the practical testwill compared in FEA (Finite Element Analysis) using ANSYS 19 R3 software onprototype and existing models. This project talk about the outline of safety helmetconstructional attributes, definition, types and choosing of suitable compositematerial.

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AGEING MODELS AND ACCELERATED AGEING TESTS OF GLASS FIBER REINFORCED CONCRETE

Engineering Structures and Technologies ◽

10.3846/est.2018.1467 ◽

2018 ◽

Vol 10 (1) ◽

pp. 10-17

Author(s):

Rimvydas MOCEIKIS ◽

Asta KIČAITĖ ◽

Gintautas SKRIPKIŪNAS ◽

Aleksandrs KORJAKINS

Keyword(s):

Composite Material ◽

Reinforced Concrete ◽

Glass Fiber ◽

Glass Fibers ◽

Fiber Reinforced Concrete ◽

Accelerated Ageing ◽

Fiber Reinforced ◽

Glass Fiber Reinforced ◽

Corrosion Mechanisms ◽

Concrete Matrix

Glass fiber reinforced concrete (GRC) is used for 40 years to create world’s most stunning and complex architectural elements due to its high mechanical properties, particularly flexural strength. Yet it is very important to note that any type of glass fibers in the concrete matrix are undergoing complex ageing processes, resulting to significant decrease of initial mechanical characteristics of this composite material under natural weathering conditions. Aspects of GRC durability are mainly dependent from the properties of fibers and interaction between them and concrete matrix. In this article, long term strength retention of this composite material is discussed, existing experimental data of weathering tests presented, and main corrosion mechanisms explained. Lack of knowledge about freeze- thaw resistance of glass fiber reinforced concrete is addressed. Finally, latest attempts of GRC durability improvement are reviewed, such as adding micro fillers, polymers to the concrete matrix and enhancing surface of fibers in Nano scale.

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Effect of the content and type of binder on the strength of glass fiber paper

Известия СПбЛТА ◽

10.21266/2079-4304.2020.232.244-251 ◽

2020 ◽

Author(s):

В.К. Дубовый ◽

Н.А. Криницин

Keyword(s):

Composite Material ◽

Metal Complexes ◽

Glass Fiber ◽

Glass Fibers ◽

Polynuclear Complexes ◽

Mineral Fiber ◽

Filter Materials ◽

Composite Filter ◽

Polynuclear Metal Complexes ◽

Technological Strength

Проведено исследование композиционного материала на основе минерального волокна с использованием в качестве связующего полиядерных комплексов металлов. Новизной и особенностью данного исследования является использование в качестве связующего для композиционного материала на основе стеклянных волокон полиядерных комплексов титана. Добавление связующего на основе полиядерных комплексов в композицию целесообразно в интервале 5–30% от массы волокна. Исследованный композиционный материал с добавлением в качестве связующего полиядерных комплексов титана имеет прочностные характеристики при рН отлива 10 и 12 выше, чем у материалов с добавлением полиядерных комплексов алюминия и обладает достаточной технологической прочностью. Полиядерные комплексы титана можно использовать как перспективные связующие для композиционных фильтровальных материалов на основе стеклянных волокон. The study of composite material based on mineral fiber using polynuclear metal complexes as a binder was carried out. The novelty and feature of this study is the use of polynuclear complexes of titanium as a binder for a composite material based on glass fibers. Adding a binder based on polynuclear complexes to the composition is advisable in the range of 5-30% by weight of the fiber. The studied composite material with the addition of polynuclear complexes of titanium as a binder has strength characteristic at pH levels 10 and 12, higher, than that of materials with the addition of polynuclear complexes of aluminum and has sufficient technological strength. Polynuclear complexes of titanium can be used as promising binders for composite filter materials based on glass fibers.

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Development and verification of mechanical characteristics of a composite material made of a thermoplastic matrix and short glass fibers

Eastern-European Journal of Enterprise Technologies ◽

10.15587/1729-4061.2021.243149 ◽

2021 ◽

Vol 5 (12(113)) ◽

pp. 30-38

Author(s):

Madina Isametova ◽

Gazel Abilezova ◽

Nikolay Dishovsky ◽

Petar Velev

Keyword(s):

Mechanical Properties ◽

Finite Element ◽

Composite Material ◽

Computer Modeling ◽

Glass Fibers ◽

Field Tests ◽

Mechanical Tests ◽

Macro Level ◽

Stage Of Development ◽

Short Glass

The paper presents the results of computer modeling and prediction of the mechanical properties of composite materials with a polycarbonate matrix filled with short glass inclusions. At the micro-level, the influence of the volume of inclusions on the mechanical properties of the designed composite based on polycarbonate matrix is studied in the DIGIMAT (France) program. It was found that with a ratio of the sizes of inclusions in the range of 468÷60, the particles have a needle shape, and the material with such inclusions has a higher stress limit and elastic modulus than with a shape coefficient less than 50. The components of the fiber orientation tensor were also determined, at which the values of computer modeling are in good agreement with experimental data. The influence of the size of the finite element grid on the characteristics of the composite at the macro level was studied, and recommendations were given for choosing the size of the face of the finite element. The adequacy of computer models was confirmed by the results of field tests. The paper presents the results of testing flat samples made by injection molding technology. Mechanical tests were carried out for three variants of samples made of composite material based on a polycarbonate matrix with 10 %, 20 % and 30 % inclusions. The discrepancy between the experimental and computer results for samples with 10 %, 20 % content of short chopped fibers is explained by the influence of technological factors on the properties of the material at the macro-level. The conducted research allowed us to develop a computer modeling technique used at the stage of development of polymer composites based on thermoplastic matrices with short glass inclusions

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Strength Study of Sorption Composites Based on Microfine Glass Fibers

Известия СПбЛТА ◽

10.21266/2079-4304.2020.233.221-227 ◽

2020 ◽

pp. 221-227

Author(s):

В.К. Дубовый ◽

Г.А. Суслов

Keyword(s):

Composite Material ◽

Organic Compounds ◽

Glass Fibers ◽

Aluminium Chloride ◽

Polynuclear Complexes ◽

Aluminium Sulfate ◽

Low Concentrations ◽

The Impact ◽

Hydrolysis Of ◽

Technological Strength

Исследуется влияние минерального и органического связующего на термостойкость и показатель разрушающего усилия композиционных сорбционных материалов на основе стеклянных волокон. Рассматриваемый материал используется для сорбции органических соединений при низких концентрациях. Изучение влияния на эти два показателя вызвано тем, что материал, описываемый в настоящей статье, требует определенной технологической прочности и должен выдерживать температуры 300 °С. Для достижения требуемых параметров для материала исследовались три типа связующего: 1. Полиядерные комплексы алюминия, полученные в результате гидролиза хлорида алюминия; 2. Полиядерные комплексы алюминия, полученные в результате гидролиза сульфата алюминия; 3. Сульфатная небеленая целлюлоза. По результатам исследования было выявлено наиболее подходящее связующее для сорбционного композиционного материала и определено оптимальное процентное содержание этого связующего. Discusses the influence of mineral and organic binders on the heat resistance and the index of the destructive force of composite sorption materials based on glass fibers. This material is used for sorption of organic compounds at low concentrations. Consideration of the impact on these two indicators is caused by the fact that the material described in this article requires a certain technological strength and must withstand temperatures of 300 °C. To achieve the required parameters for the material, three types of binder were studied: 1. Polynuclear complexes of aluminium, obtained by hydrolysis with aluminium chloride; 2. Polynuclear complexes of aluminium, obtained by hydrolysis of aluminium sulfate; 3. Sulfate unbleached cellulose. According to the results of the study, the most suitable binder for the sorption composite material was identified and the optimal percentage of this binder was determined.

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