Tribological and Microstructural Characterization of LPBF-Fabricated AlSi10Mg Composites with B₄C Reinforcement

Abstract

In this investigation, AlSi10Mg matrix composites reinforced with varying boron carbide (B4C) content (0–3 wt.%)were fabricated using the LPBF process. The SEM analysis of raw powders confirmed spherical AlSi10Mg particles and angular B4C particles. Microstructural examination of the fabricated specimens revealed a fine cellular α-Al matrix with a continuous Si-rich eutectic network. Hardness increased progressively with B4C addition, rising from approximately 132–204 HV. Owing to reinforcement of B4C reinforcement an improvement in hardness was nearly 54%. Tribological studies showed a significant reduction in wear loss, which decreased from around 2.512 mg for 0 wt.% B4C to nearly 0.715 mg for 3 wt.% B4C.SEM analysis of worn surfaces demonstrated a transition from severe adhesive and oxidative wear in monolithic AlSi10Mg to mild abrasive and delamination-controlled wear. The enhanced hardness, reduced wear loss, and stable frictional behavior confirm the effectiveness of B4C reinforcement in improving the tribological performance.