Reinforced Polymer Composite Materials Research Articles

A Study on Strength and Failure of Fabric Reinforced Polymer Composites

A Study on Strength and Failure of Fabric Reinforced Polymer Composites

Damage detection of carbon fiber reinforced polymer composite materials based on one-dimensional multi-scale residual convolution neural network

Carbon fiber reinforced polymers (CFRPs) have been widely applied in the aerospace industry, and the health conditions of CFRPs largely affect aerospace safety. Due to the limitations of traditional detection methods, electrical impedance tomography (EIT) has been gradually applied in the damage detection of CFRP composite materials. Aiming at the problems of poor imaging quality and low identification rate in the traditional EIT reconstruction algorithm, an EIT algorithm based on the one-dimensional multi-scale residual convolution neural network (1D-MSK-ResNet) is proposed in this paper. A "voltage vector-conductivity media distribution" dataset is first established, and the training results of the testing dataset are used to verify and evaluate the algorithm. Simulation and experimental results indicated that the 1D-MSK-ResNet EIT algorithm could enhance the ability of damage identification and significantly improve the imaging quality.

Effectiveness of Shannon Entropy Weight Method on Wear Behaviour of Polyester/Carbon Fibre Composites Using GRA

In recent past conventional monolithic materials are replaced with fiber reinforced polymer composite materials due to their high specific strength. The current study focused on dry-sliding wear behaviour of carbon fiber reinforced polyester (CFRP) composites using a pin-on-disc tribometer. The two output responses selected were rate of wear and frictional force with respect to controlled variables using the Taguchi L16 OA (Orthogonal Array). In order to assess the best optimal conditions GRA technique has been used in the study. The effectiveness of entropy weights on the optimal result has been carried out in support with ANOVA studies. In GRA analysis, the combined effect of wear and frictional force is considered and the optimal conditional identified in two ways namely equal weightage method (EWM) and entropy based weightage method (EBWM). While considering EWM method the optimal condition obtained is S1 L4 D3 R4 whereas in EBWM the optimal solution obtained is S1 L4 D1 R4. This shows because of the uneven weights generated by EBWM method there is a change in optimal solution in comparison with EWM method.

Study on characterization of water hyacinth (Eichhornia crassipes) novel natural fiber as reinforcement with epoxy polymer matrix material for lightweight applications

In this study, the primary goal is to utilize the biological waste of water hyacinth (Eihhornia crassipes) plant fiber–reinforced polymer composite materials for commercial applications, especially for lightweight materials aspects. In this work, the physical, mechanical (tensile, flexural, and impact), thermal, and morphological properties of water hyacinth natural fiber composite samples are investigated. We strongly believe that only a minimum amount of work has to be done to this water hyacinth fiber composite oriented. Especially all the previous literature reported the hyacinth fibers are extracted from the retting process and manual method. But, in this work, hyacinth fibers are extracted from the new novel mechanical way of the extraction process. From the results of chemical analysis, water hyacinth fiber contains a very high 62.15% cellulose content and a minimum amount (14.82%) of hemicellulose content. The crystallinity index of water hyacinth fiber composite is 54.82%. The surface of the hyacinth composite is examined with the help of a scanning electron microscope. The thermal degradation of hyacinth fiber composite is measured with the help of the thermogravimetric analysis method. Based on the final experimental results, the water hyacinth natural fiber composite is the better alternative for other traditional fiber composites and it is strongly recommended for lightweight material applications.

A life cycle assessment comparison of materials for a tidal stream turbine blade

Electricity generated from tidal streams via underwater turbines has significantly lower greenhouse gas emissions than fossil-fuel derived electricity. However, tidal stream turbine blades are conventionally manufactured from non-recyclable reinforced polymer composite materials. Tidal stream capacity is forecast to be over 1GW by 2030, which using current methods will ultimately produce around 6000 tonnes of non-recyclable blade waste. This waste is currently disposed of in landfill or incinerated, both of which have greenhouse gas and human health impacts. To address a growing waste management problem, this high-level study considers for the first time a range of conventional and bio-based materials, manufacturing methods, and end-of-life treatments to determine the blade materials and designs likely to have low environmental impact. A finite element model is used to develop material cases and Life Cycle Assessment is used to study the impacts of each over a ‘cradle to dock, dock to grave’ scope. The impact of material choices on cost and modifications to the wider turbine are considered. Compared to a glass fibre composite turbine blade, steel blades are around 2.5 times heavier, and incur additional environmental impact due to upgrades required to the wider turbine. Carbon fibre composite blades weigh less than glass fibre, but cause greenhouse 80% greater gas emissions, and human and ecosystem health risks, so are also not recommended. The best environmental performance of the cases considered was a flax fibre composite. This material offers greenhouse gas emissions around 50% lower than glass fibre materials when manufactured using conventional epoxy resin, and around 40% lower when manufactured using recyclable epoxy resin, which also enables the reuse of the fibre and may further reduce environmental impact. Initial results suggest that the cost of these materials are similar to or lower than conventional composite materials.

Recent Developments in Textile Reinforced Polymer Composites

This article provides an overview of using textile materials as reinforcement in polymer composites. A considerable amount of research studies on this topic have been conducted to date. The different types of textile materials and polymer matrices used in composite development have been discussed. The fabrication techniques used in the development of composites, the properties, testing methods and the specific standards have been critically reviewed. Furthermore, the suitable applications of textile reinforced polymer composites are reviewed. This review highlights the potential of textile materials in polymer matrices as reinforcement for various applications, including automotive, aeronautical, defence, construction industries, etc.

Low Velocity Impact Behavior of Fabric Reinforced Polymer Composites– A Review

Low Velocity Impact Behavior of Fabric Reinforced Polymer Composites– A Review

Recycling of saw dust as a filler reinforced cotton seed oil resin amalgamated polystyrene composite material for sustainable waste management applications

Recently streamlining wood waste production and promote their recovery and recycling have been popularized with the sustainable utilization of the waste generated in the saw mill to promote sound, sustainable and healthy wood waste management practices. Herein, we report the development of polymer composite from the saw dust as a reinforced filler on the natural non-edible cotton seed oil resin as feedstock amalgamated with the styrene monomer. The prepared virgin polymer saw dust (VPSD) composite holds light weight, low cost, easy handling and storage, enhanced mechanical strength, low energy production, eco-friendliness, renewability and sustainable waste management. The reinforced polymer composite material was characterized by spectroscopic and microscopic techniques. The thermal studies of the as-prepared composite shows the extended thermal degradation due to the blending of saw dust into the polymeric process and its mechanical study confirms the enhanced stiffness due to the wooden dust. Due to the significant property obtained by reinforcing the saw dust in the natural resin matrix, the process could be used to extend the development of many polymeric feedstocks as a part of sustainable waste management process.

Shear behaviour of GFRP retrofitted spiral transverse reinforced concrete beams with partially replaced recycled aggregates

The goal of this experimental investigation is to test and analyse the shear capacity of spirally reinforced concrete (RC) beams enhanced outwardly using Glass fibre reinforced polymer (GFRP) laminates with partial substitution of coarse aggregate. Over the last several years, substantial study has been undertaken in the field of Construction on the practice of Fibre Reinforced Polymer (FRP) composite materials in the retrofitting of concrete members. The FRP is placed on the webof a component with fibres aligned crosswise to the beam horizontal component for shear strengthening. Shear force resistance is obtained in the same way as embedded steel stirrups are produced: by mending shear fractures that occur beneath effective loads. GFRP may be used in a variety of ways throughout this work, based on the revealed sides of the component and the amount of strengthening sought, such as U-wraps and X-wraps in the shear zone. Environmental features are progressively being used to evaluate building material. Cementitious regeneration is becoming more popular as a means of resource conservation and eliminating necessity dumping by repurposing easily obtainable concrete as a way of adding for new concrete or other purposes. The states that really do employ recycled concrete aggregate (RCA) in fresh concrete indicate that it outperforms similarly to natural aggregate concrete. As a result, RCA is supplanted by 10% to 50%. In comparison to notional shear reinforcement, continuous spiral reinforcement of 45° was utilised as shear reinforcement to prevent shear fracturing. The load capacity, as well as its fracture formations, load deflection behaviour, and stiffness characteristics, were investigated in an actual experiment. The results of the experiment indicated that spirally reinforced concrete beams raised the maximum load much more than control beams. Furthermore, an RC beam with RCA performed better than the control beams. Additionally, spirally RC beams retrofittedwith GFRP outperformed all other forms of beams evaluated.

Experimental investigation on reinforced concrete beams retrofitted with synthetic wraps

Recently fibre reinforced polymer composite material namely glass FRP, carbon FRP, basalt FRP etc., is being used as strengthening material. Each technique has its own merits and limitations. Experimental study have been conducted on Reinforced concrete beams which are externally strengthened with GFRP and CFRP as double layer one above the other and it is referred as Hybrid FRP techniques is attained with epoxy resin as adhesive compound. All the ingredients in the beam specimens were maintained with same consistency. A total six beams were cast for the experimental investigation. Out of that three were kept as control specimens and the remaining three were strengthened with double layer of CFRP and GFRP in the U-Wrap pattern. From the overall experimental investigation it can be observed that there is an appreciable increase in ultimate load carrying capacity of the beams strengthened with hybrid FRP laminates.

Mechanical behaviour of carbon fibre reinforced polymer composite material at different temperatures: Experimental and model assessment

In the present study, temperature and frequency effects are studied involving carbon fibre reinforced polymeric materials with unidirectional fibers. Before testing, laminates were preserved in a deep freezer at −80, −20, 0, and 25°C for 60 days. Compressive, tensile, and stiffness behaviors of the laminates were assessed. The results confirmed that the compressive strength, tensile strength, and tensile modulus of laminates severely deteriorate at high temperatures. This might happen because of the weakening of the fibre/matrix interface, resulting in the load-carrying capacity of the carbon fibre being severely reduced. Lower temperatures did not significantly affect the mechanical performance of the laminates. This is due to minor deformation of the frozen laminates and closely compacted epoxy chain segments. The effects of temperature and vibration on the storage modulus, loss modulus, and damping behaviour of laminates are discussed. The results confirm that a reduction in mechanical performance is a strongly temperature-dependent phenomenon. Laminate damping properties are also evaluated. According to the results of the experiments, −80°C has the greatest permanence. Finally, the accuracy of the results on storage modulus was compared with empirical models. The model suggested by Gibson et al. provided the most accurate estimates for the storage modulus of the laminates. Other models were less accurate and gave non-conservative estimates.

Experimental investigation on hybrid fibre reinforced polymer epoxy LY556 composites by vacuum bag molding

Hybrid fiber reinforced polymer composite materials had significant properties more strength light weigh. In current research is to recognize the different stacking sequences were used. Two different fibers were namely carbon and kenaf with epox Ly556 matrix. The originality of this work is combined the natural and synthetic fibre to vaccum bag molding methods, to fabricated sandwich is used 5-layers with four sample stacking sequence are prepared. The developed Samples are cued and it has been performed various mechanical properties test. The C/C/K/C/C sacking sequences are produced 170 MPa tensile strength when compared other samples. The neat carbon fibres are have better properties, but when compared cost and environmental effect normally synthetic fibre are produced some effect.

Model, analysis of 3D structure and method for calculating the physical and mechanical characteristics of reinforced polymer composite materials

Model, analysis of 3D structure and method for calculating the physical and mechanical characteristics of reinforced polymer composite materials

Effect of fiber layering arrangement on mechanical and wear properties of flax/sisal hybrid composite laminates

To promote ecofriendly structures in engineering applications, natural fibers are preferred over the synthetic fibers in fiber reinforced polymer composite materials. However, understanding the behaviour of the natural fiber composite laminates under static and dynamic load conditions is an important aspect for the correct usage of these materials. In the present study, the effect of layering arrangement of hybrid laminates made of natural fibers on mechanical and wear characteristics have been concentrated on. In order to study the effect of layering arrangement efficiently, two different natural fibers, flax and sisal, having considerable difference in elastic modulus were preferred. All the natural fiber hybrid laminates were prepared by hand layup method. The fabricated natural fiber laminates were tested for mechanical and wear characteristics as per the ASTM standards. The fiber layering arrangement with high modulus flax fiber plied in the surface layer showed improved mechanical and wear characteristics that is beneficial for structural applications.

Optimization of machining parameters in drilling hybrid sisal-cotton fiber reinforced polyester composites

<abstract> <p>Machining natural fiber reinforced polymer composite materials is one of most challenging tasks due to the material's anisotropic property, non-homogeneous structure and abrasive nature of fibers. Commonly, conventional machining of composites leads to delamination, inter-laminar cracks, fiber pull out, poor surface finish and wear of cutting tool. However, these challenges can be significantly reduced by using proper machining conditions. Thus, this research aims at optimizing machining parameters in drilling hybrid sisal-cotton fibers reinforced polyester composite for better machining performance characteristics namely better hole roundness accuracy and surface finish using Taguchi method. The effect of machining parameters including spindle speed, feed rate and drill diameter on drill hole accuracy (roundness error) and surface-roughness of the hybrid composite are evaluated. Series of experiments based on Taguchi's L<sub>16</sub> orthogonal array were performed using different ranges of machining parameters namely spindle speed (600,900, 1200, 1600 rpm), feed rate (10, 15, 20, 25 mm/min) and drill diameter (6, 7, 8, 10 mm). Hole roundness error and surface-roughness are determined using ABC digital caliper and Zeta 20 profilometer, respectively. Optimum machining condition for drilling hybrid composite material (speed: 1600 rpm, feed rate: 25 mm/min and drill diameter: 6 mm) is determined, and the results are verified by conducting confirmation test which proves that the results are reliable.</p> </abstract>

Fabrication and preliminary assessment of aramid reinforced polymer composite material

A knowledge of the material constituents and fabrication process is generally required for easing the composite material properties study and characterization. This paper presents the methodology of aramid reinforced polymer composite material preliminary assessment and fabrication. The demonstration is carried out through the development of mechanical properties characterization specimen. The composite material specimen is fabricated by utilizing the open mould with hand lay-up method, where three types of laminates include of unidirectional, orthotropic, quasi-isotropic cross plies are demonstrated. A template is applied for preparing specific fibre orientation 45°angle. Plies are lay accordingly with guided by a square guide for minimizing the off-orientation angle defect. Preliminary assessment is included of verification of unidirectional aramid fabric quality, cured specimen physical defect, internal defect through micrography analysis and material volume fraction prediction. Average specimen fibre volume fraction of 0.64 is predicted by determined the fibre filament geometry detail through micrography analysis. There are several fabrication defects had been identified. The defect identification findings shall be referred for further improvement of material preparation and fabrication method.

Ultrasonic Evaluation of Porosity in Out-of-Autoclave Carbon Fiber–Reinforced Polymer Composite Material

Ultrasonic longitudinal wave propagation is studied in out-of-autoclave (OoA) carbon fiber–reinforced polymer composite material with varying levels of porosity contents. A combination of cure pressures and a solvent is used to produce specimens with void contents in the range of 0% to 22%. Ultrasonic measurements are made in through-transmission mode, and the data is processed to study various aspects of wave interaction with porosity in OoA specimens. The specimens with a wide range of void contents have enabled the study of broader trends of ultrasonic center frequency, wave velocity, and attenuation with respect to porosity. Results show ultrasonic center frequency and wave velocity are decreased linearly as the void content increases. The relationship of ultrasonic wave attenuation can be approximated by a logarithmic relationship when considering the full range of void content studied. Strength measurements of specimens with varying void contents are made using the flatwise tensile (FWT) test. It is observed that the strength rapidly decreases with increasing porosity. Correlations made between FWT strength, ultrasonic wave velocity, and attenuation are best described by logarithmic relationships. The data shows a potential for inferring strength knockdowns due to the presence of porosity based on ultrasonic measurements.

Development and investigation of the mechanical properties of natural fiber reinforced polymer composite

Natural fibers have an important role to play. Because of their constructive properties, reinforced polymer composite materials are increasing at a faster rate in the field of engineering and commercial application. Natural fibers have advantages over synthetic reinforcement composite. This experimentation was to investigate the mechanical behaviors such as tensile and flexural strength of natural fiber composite consist of jute and banana fiber as reinforcement and epoxy resin as matrix for two different fiber orientation (0°, 90°). From the investigation, it was examined that 0° orientation fiber had higher tensile and flexural strength compared to 90° orientation fiber. Also, it could be drawn from the experimentation that mechanical properties of composite material depend on orientation of fiber and the direction of application of load.

Classification of energy impacts by their effect on the structure and properties of reinforced reactoplasts

The use of various physical influences is an economical and highly effective direction for regulating and improving the characteristics of the modified reinforced polymer composite materials developed in this work. The methods of energy effects studied in this work were used at the stage of impregnation of technical threads of various chemical nature with an oligomeric binder and a hardener (when preparing prepregs by the traditional method) or with a binder solution and a curing system (when preparing prepregs by the method of layered application of components) Based on the conducted research, a classification of the applied methods of physical modification according to the principle of the influence of energy fields is proposed. The studied methods of energy effects are divided into orienting and energetically energizing effects. The first group includes treatments with constant magnetic (PMP) or electric fields (PEP), and constant mechanical loads. The second group includes energy effects that have a wave nature (energetically energizing), and vibration, ultrasonic effects, and ultraviolet radiation are attributed to them. Modification methods of the first group contribute to a decrease in the mobility of binder molecules during curing, while the formation of branches of polymer chains occurs during the curing process, which leads to a predominant increase in the destructive stress during static bending. Energetically energizing effects contribute to the relative acceleration of the process of linear growth of polymer chains during curing, which is accompanied by the formation of a more sparsely cross-linked mesh structure, which leads to a predominant increase in impact strength. Of the two competing processes in the curing of epoxy oligomers, this one requires a higher activation energy, which is confirmed by the results of studies. Analyzing the results obtained, it can be concluded that the modification methods used in the work allow not only to obtain polymer composite materials with high strength characteristics, but also to directly adjust the properties of composites depending on the requirements for the products. Orienting modification methods lead to hardening of the resulting polymer composite material with a predominant increase in the destructive stress during static bending from 20 to 47%. When using energetically energizing influences in the technology of producing reinforced reactoplasts, the impact strength increases mainly from 19 to 40%.

Manufacture of High-Performance Tidal Turbine Blades Using Advanced Composite Manufacturing Technologies

After wind and solar energy, tidal energy presents the most prominent opportunity for generating energy from renewable sources. However, due to the harsh environment that tidal turbines are deployed in, a number of design and manufacture challenges are presented to engineers. As a consequence of the harsh environment, the loadings on the turbine blades are much greater than that on wind turbine blades and, therefore, require advanced solutions to be able to survive in this environment. In order to avoid issues with corrosion, tidal turbine blades are mainly manufactured from fibre reinforced polymer composite material. As a result, the main design and manufacture challenges are related to the main structural aspects of the blade, which are the spar and root, and the connection between the blade and the turbine hub. Therefore, in this paper, a range of advanced manufacturing technologies for producing a 1 MW tidal turbine blade are developed. The main novelty in this study comes with the challenges that are overcome due to the size of the blade, resulting in thickness composite sections (> 130 mm in places), the fast changes in geometry over a short length that isn’t the case for wind blades and the required durability of the material in the marine environment. These advances aim to increase the likelihood of survival of tidal turbine blades in operation for a design life of 20 + years.