Mechanical and microstructure comparison between microwave and spark plasma sintering of Al–B₄C composite

In the present work, aluminum-15 wt.% boron carbide-1.5 wt.% Co composite was prepared by microwave (660 °C) and spark plasma sintering (500 °C) and the mechanical properties and microstructure of sintered samples were compared. Samples prepared by spark plasma sintering obtained higher bending strength (382 MPa) and density (2.68 g/cm³) compared to those prepared by microwave furnace (212 MPa and 2.41 g/cm³, respectively). XRD investigations indicated the decomposition of B₄C and formation of Al₃BC for microwave samples but not for SPS samples. The microstructure of sintered composites was examined and the uniform distribution of reinforced particles in the matrix was observed. - Highlights: • Al–B₄C composite was fabricated by using microwave and spark plasma sintering. • This paper presents two novel techniques to fabricate Al–B₄C composites. • Properties of Al–B₄C composite can be changed by changing sintering methods. • SPS method introduces proper properties than microwave sintering.