Vibration and tribological properties of epoxy-granite composites used as novel foundations for machine elements

Composites have become attractive to many industries today and are a good alternative to many traditional materials. Epoxy granite (EG) is used as a competitive alternative to ground ceramics, especially as a foundation for machine tools. This is because of their high damping ratio compared to other traditional materials such as cast iron. In the present study, a lightweight and cost-effective EG composite material was developed as a new foundation for machine elements. The composite material EG was prepared by mixing epoxy resin (12 wt %) and granite particles by casting method. The crushed granite particles were sieved and separated into coarse particles <= 2.36 >= 1.18 mm, medium particles <= 1.18 >= 0.6 and fine particles <= 0.6 mm. Vibration modal analysis is performed using an impact hammer to measure the natural frequencies occurring at each material size and the damping ratios. Microbial and fungal resistance is tested to understand applicability in humid environments, and water absorption and soak resistance were also measured. Scratch tests are performed using a top scratch tester to measure scratch width for fine and coarse samples. The electrostatic discharges generated by friction on the rubber and granite-epoxy composite sole are measured. It was found that as the particle size decreases, the damping ratio increases and the damping capability is improved, both microbial and fungal resistance increases, the scratch width is small for fine particles, while it is difficult to achieve for other granite sizes. Electrostatic discharges show a better feel for the composite material, but it is better with fine particles.