Effect of SiC and B₄C Reinforcements on the Structural and Mechanical Properties of Aluminum Composites Fabricated by Spark Plasma Sintering

Aluminum composites have been used for their low weight, more effective wear resistance, and suitability for high-strength purposes. It is capable of enduring the challenging environments commonly encountered in automotive and aerospace applications. The spark plasma sintering (SPS) methods, conducted at 550 °C, enhanced the aluminum matrix with ceramic particles of SiC and B₄C at varying weight percentages of 5, 10, and 15 wt.%, resulting in distinct aluminum composites, such as Al/SiC and Al/B₄C composites. In the SPS method, particle size and densification range are the primary reasons for the increase in porosity, which affects the grain structure and mechanical characteristics of the aluminum composite. The study evaluated the composite's material grain structure, density, and mechanical properties. It has been noted that the mechanical properties change and the type of reinforcement used within specific limits. Aluminum composites reinforced with ceramics exhibit improved mechanical strength. At 15 wt.% reinforcement, Al/B₄C had the maximum microhardness (88 Hv), which was higher than Al/SiC (80 Hv) with the same, brittleness occurred upward. At 10 wt.%, the highest tensile strength was reached, with Al/B₄C-210.56 MPa and Al/SiC-194.37 MPa. The material's brittleness was demonstrated by Al/B₄C, which exhibited an elongation of 8.76%, and Al/SiC was 8.97%. This indicates that the material was brittle. At 10 wt.%, Al/SiC had a greater compressive strength (257 MPa) than Al/B₄C (252 MPa). The mechanical properties of both composites were greatest when 10 wt.% reinforcement was added.