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The purpose of this paper is to understand the influence of reinforced fiber length over material‐plastic energy of deformation, clogging, crystallinity, and correlates with the friction and wear behavior of polypropylene (PP) composites under multi‐pass abrasive condition. Also to identify wear mechanisms of glass fiber reinforced PP materials under various abrasive grit sizes and normal loads.

Multi‐pass abrasive wear tests were performed for unreinforced, short, and long glass fiber reinforced PP (LFPP) on a pin on disc machine under three different normal loads and two different abrasive grit sizes for a constant sliding velocity. Measured wear volume was correlated with the plastic energy of deformation by carrying out a constant load indentation test using servo hydraulic fatigue test system. Clogging behavior of test materials was examined with the aid of online wear measurement and wear morphology. Test materials crystallinity was estimated with the aid of X‐ray diffraction investigation and correlated with abrasive wear performance.

Fiber reinforcement in a PP material is found to improve the plastic deformation energy and crystallinity which results in improved abrasive resistance of the material. Increase in reinforced fiber length is found to improve the material cohesive energy and hence the wear resistance. Reinforcement is found to alter the material clogging behavior under multi‐pass condition. Fiber reinforcement is found to reduce the material coefficient of friction, and increase in reinforced fiber length further reduces the frictional coefficient.

Friction wear tests using pin on disc equipment is carried out in the present investigation. However, in practice, part geometry may not be always equivalent to simple pin on disc configuration.

The paper's investigation results could help to improve the utilization of LFPP material in many structural applications.

Influence of reinforced fiber length over multi‐pass abrasive wear performance of thermoplastic material, and online wear measurement to substantiate clogging behavior is unique in the present multi‐pass abrasive investigation.

The need for seeking alternate materials with increased performance in the field of composites revived this research, to prepare and evaluate the mechanical properties of e-glass and aloe vera fiber-reinforced with polyester and epoxy resin matrices.

The composites are prepared by hand layup method using E-glass and aloe vera fibers with length 5-6 mm. The resin used in the preparation of composites was epoxy and polyester. Fiber-reinforced composites were synthesized at 18:82 fiber–resin weight percentages. Samples prepared were tested to evaluate its mechanical and physical properties, such as tensile strength, flexural strength, impact strength, hardness and scanning electron microscope (SEM).

SEM analysis revealed the morphological features. E-glass fiber-reinforced epoxy composite exhibited better mechanical properties than other composite samples. The cross-linking density of monomers of the epoxy resin and addition of the short chopped E-glass fibers enhanced the properties of E-glass epoxy fiber-reinforced composite.

This research work enlists the properties of e-glass and aloe vera fiber-reinforced with polyester and epoxy resin matrices which has not been attempted so far.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

The effects of the addition of short glass fibers into an acrylic‐based photo‐polymer (De Solite SCR310) used in the laser solidification process have been studied. Comparisons of the mechanical properties between pure‐polymer specimens and their fiber‐filled counterparts were made by subjecting the parts to tensile tests. It was observed that the fiber‐reinforced specimens yielded higher measured values of elastic modulus and ultimate tensile strength. The amount of shrinkage encountered by the reinforced prototypes during post‐curing was also found to be less than their non‐reinforced counterparts. It was also found that the mechanical properties of the post‐cured fiber‐reinforced specimens were functions of the layer pitch and laser exposure density used during fabrication. By increasing the laser exposure density and decreasing the layer pitch, the mechanical properties of the post‐cured fiber‐reinforced prototype can be improved, leading to the realization of end products with higher mechanical strengths and better dimensional accuracy.

This research is part of a project that aims to investigate using foamed concrete structurally in houses. Foamed concrete has a porous structure that makes it light in weight, good in thermal insulation, good in sound insulation and workable.

An experimental program is conducted in this research to investigate the behavior of polypropylene fiber reinforced foam concrete beams laterally reinforced with/without glass fiber grid.

The results proved the effectiveness and efficiency of using glass fiber grid as lateral reinforcements on the shear strength of reinforced foam concrete ribs, in reducing the cracks width and increasing its shear capacity, contrary to using glass fiber grid of reinforced foam concrete beams since glass fiber grid did not play good role in beams.

Limited literature is available regarding the structural use of foam concrete. However, work has been done in many countries concerning its use as insulation material, while limited work was done on structural type of foam concrete.

The purpose of this paper is to propose a comparative study between different structures composed of fiber-reinforced composite materials. Plates, cylinders and cylindrical and spherical shell panels in symmetric 0°/90°/0° and antisymmetric 0°/90°/0°/90° configurations are analyzed considering carbon fiber, glass fiber and linoleum fiber reinforcements.

A free vibration analysis is proposed for different materials, lamination sequences, vibration modes, half-wave numbers and thickness ratios. Such an analysis is conducted by means of an exact three-dimensional shell model which is valid for simply supported structures and cross-ply laminations. The employed model is based on a layer-wise approach and on three-dimensional shell equilibrium equations written in general orthogonal curvilinear coordinates.

The proposed study confirms the well-known superiority of the carbon fiber-reinforced composites. Linoleum fiber-reinforced composites prove to be comparable to glass fiber-reinforced composites in the case of free vibration analysis. Therefore, similar frequencies are obtained for all the geometries, thickness ratios, laminations sequences, vibration modes and a large spectrum of half-wave numbers. This partial conclusion needs further confirmations via static, buckling and fatigue analyses.

An exact three-dimensional shell model has been used to compare several geometries embedding carbon fiber composites and natural fiber composites.

In industry, fused filament fabrication (FFF) offers flexibility and agility by promoting a reduction in costs and in the lead-time (i.e. time-to-market). Nevertheless, FFF parts exhibit some limitations such as lack of accuracy and/or lower mechanical performance. As a result, some alternatives have been developed to overcome some of these restrictions, namely, the formulation of high performance polymers, the creation of fibre-reinforced materials by FFF process and/or the design of new FFF-based technologies for printing composite materials. This work aims to analyze these technologies.

This work aims to study and understand the advances in the behaviour of 3D printed parts with enhanced performance by its reinforcement with several shapes and types of fibres from nanoparticles to continuous fibre roving. Thus, a comprehensive survey of significant research studies carried out regarding FFF of fibre-reinforced thermoplastics is provided, giving emphasis to the most relevant and innovative developments or adaptations undergone at hardware level and/or on the production process of the feedstock.

It is shown that the different types of reinforcement present different challenges for the printing process with different outcomes in the part performance.

This review is focused on joining the most important researches dedicated to the process of FFF-printed parts with different types reinforcing materials. By dividing the reinforcements in categories by shape/geometry and method of processing, it is possible to better quantify performance improvements.

Natural fiber composites have been proven an alternative to conventional composites in many applications such as automotive and transportation industries owing to their eco-friendliness and abundant availability. Also, they are recyclable and biodegradable. Therefore, the need for composites having superior performance is increasing consistently, which has prompted the research reported in this paper. This paper aims to fabricate and evaluate the properties of hybrid composites using glass and cotton fiber with epoxy resin.

They were prepared by hand lay-up method, using e-glass and cotton fibers. Epoxy resin used in the preparation of composites. The composites were hybridized at two weight percentages (20 and 30 Wt.%). The prepared samples were tested to evaluate its properties, such as tensile strength, flexural strength, impact strength and scanning electron microscope .

Microscopic examination revealed the morphological features. Hybrid fiber reinforced epoxy composite (HFREC) exhibited better mechanical properties than the individual samples. It is clear that 30 Wt.% fraction of fiber is better in mechanical properties than 20 Wt.% fraction of fiber reinforcement in both glass fiber and cotton fiber as reinforcement. Also, the hybridization of fibers resulted in increase in properties.

As cotton fibers are biodegradable, recyclable and lightweight, it has many applications and is mainly used as automotive components, aerospace parts, sporting goods and building industry when reinforced with glass and epoxy. With this scenario, the obtained results of cotton fiber reinforced composites are not ignorable, which could be of potential use, as it leads to better use of available natural fibers.

This work discovered the properties of e-glass and cotton fiber reinforced epoxy resin hybrid composites (hybridized at different weight percentages), which has not been attempted so far.

The purpose of this paper is to investigate the existence of SH-waves in fiber-reinforced layer placed over a heterogeneous elastic half-space.

The heterogeneity of the elastic half-space is caused by the exponential variations of density and rigidity. As a special case when both the layers are homogeneous, the derived equation is in agreement with the general equation of Love wave.

Numerically, it is observed that the velocity of SH-waves decreases with the increase of heterogeneity and reinforced parameters. The dimensionless phase velocity of SH-waves increases with the decreases of dimensionless wave number and shown through figures.

In this work, SH-wave in a fiber-reinforced anisotropic medium overlying a heterogeneous gravitational half-space has been investigated analytically and numerically. The dispersion equation for the propagation of SH-waves has been observed in terms of Whittaker function and its derivative of second degree order. It has been observed that on the removal of heterogeneity of half-space, and reinforced parameters of the layer, the derived dispersion equation reduces to Love wave dispersion equation thereby validates the solution of the problem. The equation of propagation of Love wave in fiber-reinforced medium over a heterogeneous half-space given by relevant authors is also reduced from the obtained dispersion relation under the considered geometry.

The main idea is the comparison between composites including natural fibres (such as the linoleum fibres) and typical composites including carbon fibres or glass fibres. The comparison is proposed for different structures (plates, cylinders, cylindrical and spherical shells), lamination sequences (cross-ply laminates and sandwiches with composite skins) and thickness ratios. The purpose of this paper is to understand if linoleum fibres could be useful for some specific aerospace applications.

A general exact three-dimensional shell model is used for the static analysis of the proposed structures to obtain displacements and stresses through the thickness. The shell model is based on a layer-wise approach and the differential equations of equilibrium are solved by means of the exponential matrix method.

In qualitative terms, composites including linoleum fibres have a mechanical behaviour similar to composites including glass or carbon fibres. In terms of stress and displacement values, composites including linoleum fibres can be used in aerospace applications with limited loads. They are comparable with composites including glass fibres. In general, they are not competitive with respect to composites including carbon fibres. Such conclusions have been verified for different structure geometries, lamination sequences and thickness ratios.

The proposed general exact 3D shell model allows the analysis of different geometries (plates and shells), materials and laminations in a unified manner using the differential equilibrium equations written in general orthogonal curvilinear coordinates. These equations written for spherical shells degenerate in those for cylinders, cylindrical shell panels and plates by means of opportune considerations about the radii of curvature. The proposed shell model allows an exhaustive comparison between different laminated and sandwich composite structures considering the typical zigzag form of displacements and the correct imposition of compatibility conditions for displacements and equilibrium conditions for transverse stresses.