Effectiveness of carbon microcoils as a reinforcing material for a polymer matrix

Spring-shaped carbon microcoils (CMCs) were embedded in epoxy resins to form CMC/epoxy resin composites. The mechanical properties of the composites were examined and compared with those of conventional straight carbon fiber (CF) /epoxy resin composites. CMCs were found to be more effective than CFs as a reinforcing material for the epoxy resin having a low Young’s modulus (0.54 MPa). SEM images of the fractured cross-sections of the composite revealed that CMCs were not pulled out from the resin matrix but fractured with the matrix. This could be ascribed to the unique conformations of CMCs.