Abstract. The goal of this paper is to determine the mechanical properties of a proposed combined polymer composite which consist of a poly-vinyl alcohol (PVA) matrix and palm kernel fibre reinforced with epoxy. The influence of fibres volume on the mechanical properties of the composites was also evaluated. Composites with volumetric amounts of palm kernel fibre up to 12 % were fabricated and they were arranged in randomly oriented discontinues form. Tensile, impact, flexural and hardness tests were carried out to determine the characteristics of material. The acquired results show that the tensile modulus changes with the fibre content. The strength of coconut fibre reinforced composites tends to decrease with the amount of fibre which indicates ineffective stress transfer between the fibre and matrix. When higher fibre content of 10% was used, the damping peak shows the maximum value for almost all the frequency mode. It was observed that the effects of reinforcing poly-vinyl alcohol (PVA matrix with the palm kernel fibres caused the composites to be more flexible and easily deform due to high strain values and reduction of high resonant amplitude. In general, the mechanical properties of the developed composite showed variation at different test performed. This led to the conclusion that the material is most useful were strength to weight ratio is needed. The optimum percentage of fibre in epoxy resin to obtain the highest tensile properties was found at 10 vol. %. It was also found that fibre, dispersion of fibre and interfacial adhesion between fibre-matrix can affect the mechanical properties of the composites.

The goal of this paper is to determine the mechanical properties of a proposed combined polymer composite which consist of a poly-vinyl alcohol (PVA) matrix and palm kernel fibre reinforced with epoxy. The influence of fibres volume on the mechanical properties of the composites was also evaluated. Composites with volumetric amounts of palm kernel fibre up to 12 % were fabricated and they were arranged in randomly oriented discontinues form. Tensile, impact, flexural and hardness tests were carried out to determine the characteristics of material. The acquired results show that the tensile modulus changes with the fibre content. The strength of coconut fibre reinforced composites tends to decrease with the amount of fibre which indicates ineffective stress transfer between the fibre and matrix. When higher fibre content of 10% was used, the damping peak shows the maximum value for almost all the frequency mode. It was observed that the effects of reinforcing poly-vinyl alcohol (PVA matrix with the palm kernel fibres caused the composites to be more flexible and easily deform due to high strain values and reduction of high resonant amplitude. In general, the mechanical properties of the developed composite showed variation at different test performed. This led to the conclusion that the material is most useful were strength to weight ratio is needed. The optimum percentage of fibre in epoxy resin to obtain the highest tensile properties was found at 10 vol. %. It was also found that fibre, dispersion of fibre and interfacial adhesion between fibre–matrix can affect the mechanical properties of the composites.

The effect of various heat treatment operations (annealing, normalizing, tempering) on mechanical properties of 0.35% carbon steel was investigated. The change in the value of endurance limit of the material as a result of the various heat-treatment operations were studied thoroughly. It was found that the specimens tempered at low temperature (200°C) exhibited the best fatigue strength. Microscope was used to characterize the structural properties resulting from different heat treatment processes. The results from the tensile tests impact tests and hardness tests showed that the mechanical properties variate at every heat-treatment conditions. The microstructure of differently heat-treated steels was also studied.

Abstract. The effect of various heat treatment operations (annealing, normalizing, tempering) on mechanical properties of 0.35% carbon steel was investigated. The change in the value of endurance limit of the material as a result of the various heat-treatment operations were studied thoroughly. It was found that the specimens tempered at low temperature (200 0 C) exhibited the best fatigue strength. Microscope was used to characterize the structural properties resulting from different heat treatment processes. The results from the tensile tests impact tests and hardness tests showed that the mechanical properties variate at every heat-treatment conditions. The microstructure of differently heat-treated steels was also studied.