Effect of Volume Fraction of Epoxy Matrix Coconut Shell Composite on Tensile and Impact Loads

This research aims to determine the effect of the volume fraction of coconut shell composite, with an epoxy matrix at 10% coconut shell water content, on the composite's tensile strength, impact, density, and fracture results with the macrostructure. The materials used to make this composite are coconut shell particles, with a diameter of 1mm at a water content of 10%, and epoxy matrix and hardener, in a ratio of 1:1. Variations in volume fraction are 10%, 20%, 30%, 40% and 50%. The composite was manufactured using a press mold. Composite testing was in accordance with ASTM standards for tensile testing, using ASTM D 638-02 and impact testing using ASTM D 256-00. Macro photo results that determine the type of fracture that occurred were taken of the fracture resulting from tensile and impact tests. The test results showed that the highest tensile strength was at a volume fraction of 40% of 21.59 MPa, and the lowest was at 10% of 7.15 MPa. The highest impact value was shown in a composite with a volume fraction of 50% of 0.074 J/mm2, and the lowest had a volume fraction of 10% of 0.010 J/mm2. The highest density was a composite with a volume fraction of 50% of 1.067 gr/cm3, and the lowest had a volume fraction of 10% of 1.014 gr/cm3. In observing the fracture after tensile and impact testing, it can be seen that the fracture was brittle, and the direction of crack propagation is perpendicular to the direction of the tensile stress that is acting to produce a relatively flat fracture surface.