Abstract:
This study is about the production and characterization of epoxy-rice husk ash composite. Composites were produced at 10%,20%,30%,40% and 50% volume fraction of Rice Husk Ash(RHA) fillers and the epoxy was cast neat at 0%RHA which served as the control .The microstructure of the composites were studied with Scanning Electron Microscopy(SEM) and Energy Dispersive X-ray Spectroscopy(EDX).Mechanical properties of the composites such as tensile properties(tensile stress, tensile strain, Young’s modulus, tensile strength and percentage elongation at fracture),compressive strength, toughness, flexural strength and hardness were experimentally determined in the engineering labouratory using hounsfield (monsanto) tensometer, charpy v-notch impact testing machine, flexural testing machine and Rockwell hardness testing machine. The Scanning Electron Microscopy (SEM) analysis showed that interfacial interactions existed between the rice husk ash particles and the epoxy matrix. Energy Dispersive X-ray Spectroscopy (EDX) analysis indicated that interfacial reactions existed between the epoxy matrix and the rice husk ash particles because the composites did not contain homogenous elements. However each of the composites contained C,O,Si and Cl while the cast neat epoxy(control) contained C,O and Cl. Results of the mechanical property tests showed low gain in hardness, toughness, flexural strength and Young’s modulus. The tensile properties showed: that at 40%RHA the highest tensile strength of 37.006MPa was obtained, the cast neat epoxy (control 0%RHA) had the best Young’s modulus of 356.538MPa and percentage elongation at fracture improved from 1.3% to 2.0% as volume fraction of rice husk ash increased from 0% to 10%,20%,30%,40% and 50%.Increasing the volume fraction of rice husk ash from 0% to 10%, 20%,30%,40% and 50% led to decrease of these mechanical properties: toughness from 2.0J to 0.3J,hardness from 344hardness value to 144 hardness value and flexural strength from 6.0Mpa to 1.50Mpa.There was significant improvement in the compressive strength of the composites from 15.75MPa to 18.75MPa as the volume fraction of rice husk ash increased from 0% to 10%,20%,30%,40% and 50%.It was deduced from the study that epoxy-rice husk ash composite is suitable for engineering applications subjected to compression. Surface coating of rice husk ash could be used to improve its adhesion to the epoxy matrix in order to enhance the mechanical properties of the composites for other engineering applications.
