Assessment of reclaimed carbon dust utilization as a filler in thermoset polymer composites: analysis of strength properties and curing effects

Abstract

Carbon dust (CD) emerged as a by-product during the machining of carbon fibre reinforced polymer (CFRP) composites, generally relegated to landfills or subjected to partial recycling. The utilization of CD as a filler material in polymer composites is still in its early stages, hindered by difficulties in the reclamation process and in managing the distribution of CD during polymer processing. This study examined the feasibility of utilizing reclaimed carbon dust (rCD) as a substitute filler for virgin carbon fiber in thermoset polymers. The study evaluated the mechanical properties of rCD-filled composites, examined the impact of several curing techniques (vacuum bagging and autoclave), and analyzed the dispersion of carbon dust by scanning electron microscopy (SEM). Samples with rCD content between 0% and 30% were produced, and different curing conditions were assessed. The findings demonstrated that an increase in rCD content resulted in diminished tensile strength, whereas compression strength was enhanced. SEM research indicated that increased rCD content led to insufficient adhesion between the resin and rCD particles, hence lowering tensile strength. Nonetheless, autoclave curing enhanced tensile strength by minimizing void content and porosity. While rCD showed potential for enhancing compression strength, challenges with tensile strength and adhesion highlighted the need for further optimisation of processing parameters and resin compatibility for broader industrial applications.