Mechanical, microstructural, and corrosion evaluation of Fe-SiC-Al2O3 hybrid composites fabricated by powder metallurgy

Abstract

The study presents the hybrid composite fabricated using an Fe matrix reinforced with Al₂O₃ and SiC via powder metallurgy (PM) with high-energy milling balls. Graphite was used as a lubricant in the PM process. Physical, mechanical, and microstructural properties of the hybrid composite were studied. The effect of reinforcement on hardness and porosity was studied, and the results indicated that pure iron exhibited lower hardness than the composite. In addition, the microstructure characterization showed that the presence of Fe, Al₂O₃, SiC, FeAl₂O₄, Gr, Fe₂O₃, agglomeration, and porosity in the developed hybrid composite. Based on the result obtained from the sample developed using the Taguchi L₉ orthogonal array method, the optimal hardness, compressive strength, and Young's modulus were obtained at 611.8HV, 262 MPa, and 187.8 GPa, respectively. Results showed an improvement of 88% in hardness, 20% in compressive strength, and 79% in Young's modulus. The corrosion test showed that the hybrid composite exhibited higher corrosion resistance than pure iron. Moreover, increasing the reinforcement increases the corrosion resistance.