3:20 PM - 3:40 PM
[15F-T13-05] Effect of Reinforcement Particle Size on the Corrosion and Mechanical Properties of Spark Plasma Sintered Aluminium Matrix Composites
Keywords:Composites, Spark plasma sintering, Recrystallization, Corrosion, Mechanical properties
This study investigates the influence of reinforcement particle size on the corrosion and mechanical properties of spark plasma sintered aluminum (Al) matrix composites. The process parameters of spark plasma sintering (SPS), such as electrical power, pressure and temperature, are systematically investigated to understand their influence on the densification behavior and microstructure development. The results show a complex interplay between the process conditions and the particle properties that affect the sintering kinetics and the resulting microstructure. Mechanical analyzes show that particle size distribution significantly influences hardness, with an initial increase followed by a slight decrease as the ratio of nano to micro Al2O3 particles varies. Microstructural observations using SEM images confirm the role of particle size in changing the grain boundaries, distribution and overall matrix structure. Potentiodynamic polarization curves in a 0.1 M NaCl solution showed that the corrosion potential (Ecorr) remained constant between samples, while the corrosion current density (Icorr) exhibited significant variations. Nano-sized Al2O3 particles improved the corrosion resistance, in contrast to the degradation caused by microparticles. In particular, the bimodal structure showed a 3.5-fold improvement in corrosion resistance compared to pure Al. The Al-2n8mAl2O3 sample, which showed active behavior at high potentials without a limited passivation range, further underlined the influence of particle size. The study highlights the potential of bimodal microstructures for improved uniformity and corrosion resistance, although further investigation is required for a comprehensive understanding of the underlying mechanisms.