Purpose This paper aims to investigate the tensile behavior of epoxy and polyester matrix composites reinforced with continuous and aligned aloe vera fibers. Design/methodology/approach Composites with different volume fractions (30, 40 and 50 Vol. %) were fabricated by laying the fibers in a steel mould and pouring liquid resin, either DEGEBA/TETA epoxy or methyl-ethyl ketone hardened orthophthalic polyester, under pressure of 3 MPa. The specimens were cured for 24 h at room temperature and then tested in a universal Instron testing machine, model 5582, at 298 K (25°C). Findings The fracture surface was analyzed by scanning electron microscopy (SEM) under an acceleration voltage of 15 kV. SEM fractography revealed a poor adhesion between both the epoxy and polyester matrices with the aloe vera fiber. The results showed that in both cases the introduction of aloe vera fibers had a minor effect on the matrix reinforcement. Originality/value Investigation and comparison of tensile behavior of epoxy and polyester matrix composites reinforced with continuous and aligned aloe vera fibers have not been attempted so far.

Purpose 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. Design/methodology/approach 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). Findings 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. Originality/value 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.

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Purpose The main purpose of this proposed parabolic leaf spring (PLS) is to reduce the weight of the steel leaf spring by developing a new design, to increase the load-carrying capacity, to increase the ride comfort for the passengers and also to achieve a substantial weight reduction in the suspension system by replacing the semi-elliptic leaf spring. Design/methodology/approach The semi-elliptic steel leaf spring and the PLS are compared based on the load-carrying capacity and weight. The design constraints are stresses and deflection. The dimensions of the HM trekker Jeep semi-elliptic leaf springs are taken. A three-dimensional model is created, and the static structural analysis is performed. The semi-elliptic leaf spring is tested on a universal testing machine, and the experimental result is compared with the analytical result for the validation. After validation, the stress analysis of the PLS is carried out and compared with the stress analysis of the semi-elliptic leaf spring. Findings The results show that the developed PLS performs better than the semi-elliptic leaf spring in terms of load-carrying capacity and weight reduction. Originality/value Comparison between the semi-elliptic leaf spring and the PLS (static structural analysis and dynamic analysis) has not been carried out before.

Delamination (the separation between plies) is a common failure in Fiber Reinforced Polymer (FRP) laminated composites. The presence of delamination reduces the structural stiffness and changes in dynamic responses. The change in dynamic parameters can be successfully used for assessing structural health monitoring (SHM) for composite structures. SHM requires large amount of numerical/experimental data. This study focuses on the influence of the delamination parameters (size and in-plane location) on vibration behavior of a laminated tapered fiber reinforced polymer (FRP) composite plate with ply drop-off. Furthermore, developing a surrogate model as a fast-executing model to predict the shift in the natural frequency to reduce the computational effort for solving forward problems. The layerwise theory (LWT) has been used, and the delamination is modeled by “constrained mode” were solved using the finite element method (FEM). The numerical model was validated with an experimental modal analysis of tapered plates without delamination to make the model more robust. The effect of delamination was studied using surface plots produced using response surface methodology (RSM). The results show that the delamination size and location significantly affect the natural frequency shift. The RSM and ANN models were considered as surrogate models, and it was evaluated using an experimental modal analysis. The results shows that the single-output ANN model can predict the shift in the natural frequency with a minimum Root Mean Square Error (RMSE).