Enhancing strength and damping: a study on the mechanical and vibrational properties of cast iron reinforced granite-epoxy hybrid composite

Precision machine tool structures require enhanced stability with higher static stiffness and increased damping. Granite epoxy (G-E) composite offers improved damping properties and is a promising alternative material. This study evaluates the mechanical strength and damping of G-E hybrid polymer composites with varying percentages of cast iron (CI) filler. Experimental and finite element (FE) analyses were conducted on hybrid composite samples incorporating 5, 10 and 15 wt% CI filler particles. Results show that a 70:30 ratio of G-E with 10% CI filler enhances compressive strength. Tensile and flexural behaviors are influenced by epoxy content, with minimal effects from CI filler. Both experimental and numerical simulations show significant improvement in stiffness and damping properties with higher quantities of granite particulates (80 wt%) and 5 wt% CI filler. Modal analysis confirms higher natural frequencies in all modes. This hybrid composite configuration presents a viable alternative for machine tool structures, offering increased structural damping.