Microstructure and Mechanical Properties of Core-Shell B₄C-Reinforced Ti Matrix Composites

Composite material uses ceramic reinforcement to add to the metal matrix to obtain higher material properties. Structural design is an important direction of composite research. The reinforcement distribution of the core-shell structure has the unique advantages of strong continuity and uniform stress distribution. In this paper, a method of preparing boron carbide (B₄C)-coated titanium (Ti) powder particles by ball milling and preparing core-shell B₄C-reinforced Ti matrix composites by Spark Plasma Sintering was proposed. It can be seen that B₄C coated on the surface of the spherical Ti powder to form a shell structure, and B₄C had a certain continuity. Through X-ray diffraction characterization, it was found that B₄C reacted with Ti to form layered phases of titanium boride (TiB) and titanium carbide (TiC). The compressive strength of the composite reached 1529.1 MPa, while maintaining a compressive strain rate of 5%. At the same time, conductivity and thermal conductivity were also characterized. The preparation process of the core-shell structure composites proposed in this paper has high feasibility and universality, and it is expected to be applied to other ceramic reinforcements. This result provides a reference for the design, preparation and performance research of core-shell composite materials.