Simultaneously increasing the mechanical properties and corrosion resistance of B₄C/Al composites via forming “TiO₂–Al” interfacial layer

In this work, we use a simple and efficient method to introduce “TiO₂–Al” interfacial layers between the B₄C particles and aluminium (Al) matrix in TiO₂@B₄C/Al composites by combining the ball milling dispersion process with the pressure infiltration technology. It is anticipated that it would improve the mechanical properties and corrosion resistance. The work demonstrates that the coefficient of thermal expansion (CTE) of the “TiO₂–Al” interfacial layer is between those of the matrix and the reinforcement. Thus, it relieves the residual stresses in the composites. Furthermore, the low residual stress of the composites achieved by introducing the “TiO₂–Al” interfacial layer results in delayed failure and the low corrosion tendency. The composites containing “TiO₂–Al” interfacial layers show remarkable bending properties (a strength of 668.6 MPa) and good corrosion resistance (a low corrosion current density of 6.81 μA cm⁻²). Thus, the TiO₂@B₄C/Al composites exhibit remarkable mechanical properties and corrosion resistance compared with the composites reported in the literature.