Recently, there has been a rapid growth in research and innovation in the natural fibre composite (NFC) area. Interest is warranted due to the advantages of these materials compared to others, such as synthetic fibre composites, including low environmental impact and low cost and support their potential across a wide range of applications. Much effort has gone into increasing their mechanical performance to extend the capabilities and applications of this group of materials. This review aims to provide an overview of the factors that affect the mechanical performance of NFCs and details achievements made with them.

A review of recent developments in natural fibre composites and their mechanical performance

This paper is a review on the tensile properties of natural fiber reinforced polymer composites. Natural fibers have recently become attractive to researchers, engineers and scientists as an alternative reinforcement for fiber reinforced polymer (FRP) composites. Due to their low cost, fairly good mechanical properties, high specific strength, non-abrasive, eco-friendly and bio-degradability characteristics, they are exploited as a replacement for the conventional fiber, such as glass, aramid and carbon. The tensile properties of natural fiber reinforce polymers (both thermoplastics and thermosets) are mainly influenced by the interfacial adhesion between the matrix and the fibers. Several chemical modifications are employed to improve the interfacial matrix–fiber bonding resulting in the enhancement of tensile properties of the composites. In general, the tensile strengths of the natural fiber reinforced polymer composites increase with fiber content, up to a maximum or optimum value, the value will then drop. However, the Young’s modulus of the natural fiber reinforced polymer composites increase with increasing fiber loading. Khoathane et al. [1] found that the tensile strength and Young’s modulus of composites reinforced with bleached hemp fibers increased incredibly with increasing fiber loading. Mathematical modelling was also mentioned. It was discovered that the rule of mixture (ROM) predicted and experimental tensile strength of different natural fibers reinforced HDPE composites were very close to each other. Halpin–Tsai equation was found to be the most effective equation in predicting the Young’s modulus of composites containing different types of natural fibers.

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A review on the tensile properties of natural fiber reinforced polymer composites

Biodegradable composites based on lignocellulosic fibers—An overview

Natural fibers are getting attention from researchers and academician to utilize in polymer composites due to their ecofriendly nature and sustainability. The aim of this review article is to provide a comprehensive review of the foremost appropriate as well as widely used natural fiber reinforced polymer composites (NFPCs) and their applications. In addition, it presents summary of various surface treatments applied to natural fibers and their effect on NFPCs properties. The properties of NFPCs vary with fiber type and fiber source as well as fiber structure. The effects of various chemical treatments on the mechanical and thermal properties of natural fibers reinforcements thermosetting and thermoplastics composites were studied. A number of drawbacks of NFPCs like higher water absorption, inferior fire resistance, and lower mechanical properties limited its applications. Impacts of chemical treatment on the water absorption, tribology, viscoelastic behavior, relaxation behavior, energy absorption flames retardancy, and biodegradability properties of NFPCs were also highlighted. The applications of NFPCs in automobile and construction industry and other applications are demonstrated. It concluded that chemical treatment of the natural fiber improved adhesion between the fiber surface and the polymer matrix which ultimately enhanced physicomechanical and thermochemical properties of the NFPCs.

/pdf/a-review-on-natural-fiber-reinforced-polymer-composite-and-24eoqfvi7o.pdf

A Review on Natural Fiber Reinforced Polymer Composite and Its Applications

In recent years, the use of flax fibres as reinforcement in composites has gained popularity due to an increasing requirement for developing sustainable materials. Flax fibres are cost-effective and offer specific mechanical properties comparable to those of glass fibres. Composites made of flax fibres with thermoplastic, thermoset, and biodegradable matrices have exhibited good mechanical properties. This review presents a summary of recent developments of flax fibre and its composites. Firstly, the fibre structure, mechanical properties, cost, the effect of various parameters (i.e. relative humidity, various physical/chemical treatments, gauge length, fibre diameter, fibre location in a stem, oleaginous, mechanical defects such as kink bands) on tensile properties of flax fibre have been reviewed. Secondly, the effect of fibre configuration (i.e. in forms of fabric, mat, yarn, roving and monofilament), manufacturing processes, fibre volume, and fibre/matrix interface parameters on the mechanical properties of flax fibre reinforced composites have been reviewed. Next, the studies of life cycle assessment and durability investigation of flax fibre reinforced composites have been reviewed.

Flax fibre and its composites – A review

In the past decade, natural-fiber composites with thermoplastic and thermoset matrices have been embraced by European car manufacturers and suppliers for door panels, seat backs, headliners, package trays, dashboards, and interior parts. Natural fibers such as kenaf, hemp, flax, jute, and sisal offer such benefits as reductions in weight, cost, and CO2, less reliance on foreign oil sources, and recyclability. However, several major technical considerations must be addressed before the engineering, scientific, and commercial communities gain the confidence to enable wide-scale acceptance, particularly in exterior parts where a Class A surface finish is required. Challenges include the homogenization of the fiber's properties and a full understanding of the degree of polymerization and crystallization, adhesion between the fiber and matrix, moisture repellence, and flame-retardant properties, to name but a few.

Natural-fiber-reinforced polymer composites in automotive applications

One of the primary projected advantages of the new cyclic thermoplastic- based composites, in addition to their ability to be processed by liquid composite molding, is their potential "recyclabilit...

Recycling of a Cyclic Thermoplastic Composite Material by Injection and Compression Molding

An investigation has been carried out on the friction stir welding of magnesium alloy, AM60. Casting samples have each been welded and their mechanical properties were presented. The microstructure and defect formation were conducted by optical and scanning electron microscopes. More attention was paid to failure mode of welded pieces near joined area or socalled thermo-mechanical affected zone under tension and voids formed during friction stir welding. In addition, the effect of FSW processing parameters and casting thickness on the mechanical properties will be presented. At the end, a cost analysis using friction stir welding for magnesium application on the Ford GT vehicles will be presented.

Friction stir welding of magnesium am60 alloy

Tensile properties of die cast magnesium AM60 were investigated by testing tensile bar specimens obtained from three sources. The first series of tensile bars were cut from eight locations from multiple copies of a die cast magnesium AM60 automotive instrument panel beam. The second series were cut from six-inch square AM60 die cast plates in both the parallel and perpendicular to the flow direction. The last series of specimens were die cast AM60 tensile bars. The measured yield stress did not significantly depend on the specimen source and matched published values. However, the elongation as determined by the engineering strain at break in the tensile test varied significantly for samples cut from the automotive instrument panel beams and those cut from the six-inch by six-inch plates. The elongation remained constant for the cast tensile bars. Statistic General Linear Models were used to study the effect of casting conditions on both the yield stress and the strain at break. Sample location within the beams was the main factor for the material property variation.Copyright © 2004 by ASME

Elongation Variability of AM60 Die Cast Specimens

A method and apparatus for molding panels, the apparatus including upper and lower mold dies, a sprayer that sprays resin onto the lower mold die, and a wiper seal ring that's disposed in a position to form a vacuum chamber between the upper and lower mold dies as the mold dies are moving together from an initial sealing position to a closed position. A vacuum source draws air from the vacuum chamber as the mold dies are closing. The vacuum draws trapped air from within the sprayed-on resin to provide a superior class-A surface.

Dan Houston

Papers

Natural-fiber-reinforced polymer composites in automotive applications

Recycling of a Cyclic Thermoplastic Composite Material by Injection and Compression Molding

Friction stir welding of magnesium am60 alloy

Elongation Variability of AM60 Die Cast Specimens

Panel molding method and apparatus