Effect of silicon carbide powder on asphalt material properties and microwave-induced self-healing

Silicon carbide (SiC) powder, an excellent microwave-absorbing material, can serve as a filler in asphalt mixtures. This study compares the particle size distribution, phase composition, pore structure, specific surface area, and electromagnetic properties of SiC powder and limestone powder. Asphalt mastic and mixtures were prepared with SiC powder replacing mineral powder at ratios ranging from 0 % to 60 %. The study examines how differences in particle size gradation, mineral composition, pore structure, and specific surface area contribute to deformation resistance and improve mechanical properties through micro-level interlocking and cementation. Electromagnetic parameter variations affect microwave heating performance, with uniform distribution of absorbing fillers ensuring heating homogenization. SiC powder also enhances the self-healing index, reaching 74.4 %, and maintaining a maximum healing index of 68.1 % after four damage-healing cycles. These findings support the practical application of SiC powder in asphalt concrete, enhancing maintenance efficiency and advancing microwave heating for self-healing and hot recycling.