Fabrication and Mechanical Properties of Boron Carbide Particle-Reinforced Aluminum Matrix Composite Using Wet Shear Pulverization and Spark Plasma Sintering

Abstract

Aluminum (Al) matrix composites (AMCs) reinforced with boron carbide (B4C) particles were produced using a combination of wet shear pulverization (WSP) and spark plasma sintering (SPS). The WSP process, which generates high shear stress in an ethanol medium, enabled uniform dispersion of B4C particles and effectively reduced agglomeration compared to traditional hand mixing. However, oxygen analysis showed a slight increase in oxidation after WSP processing, a nanoscale Al–Al2O3 interfacial layer, known as the marble pattern, formed and contributed to improved particle–matrix bonding. Microstructural studies revealed that WSP-treated composites exhibited a uniform distribution of B4C particles and a dense microstructure, while hand-mixed samples displayed uneven dispersion and localized oxide formation. The Al–10 vol% B4C composite produced by WSP achieved an ultimate tensile strength of 201 MPa and a fracture elongation of 19.4%, both surpassing the values reported for previous Al–B4C composites. These findings confirm that WSP is an effective powder-processing method for enhancing the interfacial structure and mechanical properties of Al–B4C composites.