Aluminium matrix composites are increasingly valued for their exceptional mechanical properties, making them vital in automotive and aerospace industries that demand enhanced wear resistance and hardness. This study focuses on the fabrication of hybrid aluminium matrix composites reinforced with Boron Carbide (B₄C) and Boron Nitride (BN) particles via a novel method called friction-stir processing. The influences of the key process parameters, tool rotational speed, tool traverse speed, axial force, and powder ratio on the mechanical properties of the composites were investigated. The experiments were conducted according to the Central Composite Design and empirical models were developed to predict the microhardness and specific wear rate. The results were validated through Analysis of Variance and Response Surface Methodology. The optimal FSP conditions were identified as a rotational speed of 1300 rpm, transverse speed of 15 mm/min, axial force of 8 kN, and powder ratio of 50% B₄C + 50% BN. The maximum microhardness observed was 135 HV, indicating a 26% enhancement relative to the Al Alloy. Additionally, the specific wear rate was minimized to 0.15 × 10^-6 mm³/Nm. The incorporation of lubricant BN particles in equal weight percentages with B₄C particles resulted in a notable enhancement in wear resistance.

Keywords: Composite materials, Mathematical modelling, Mechanical properties, Electron microscopy.