Microstructure and Mechanical Properties of Al6060/TiB2 Aluminum Matrix Composites Produced via Ultrasonically Assisted Stir Casting and Radial-Shear Rolling

Abstract

Lightweight aluminum matrix composites with superior strength and structural integrity are in high demand for next-generation transportation and aerospace applications. In this work, Al6060-based composites reinforced with ≈2 wt.% TiB2 were produced using a hybrid processing route that combines ultrasonically assisted stir casting with radial-shear rolling (RSR). This strategy enabled uniform particle dispersion, strong matrix–reinforcement bonding, and substantial microstructural refinement (grain size 4–6 μm) with reduced porosity. Consequently, the Al6060/TiB2 composites demonstrated substantial gains over the as-cast alloy, combining a yield strength of 108.6 MPa, ultimate tensile strength of 156.9 MPa, and microhardness of 76.3 HV0.2 with a balanced ductility of ~9%. The demonstrated synergy of ultrasound-assisted casting and severe plastic deformation highlights a scalable pathway for fabricating high-performance aluminum composites, positioning them as promising candidates for aerospace, automotive, and other advanced engineering sectors.