Effect of TiC layer thickness on the thermal conductivity and mechanical properties of Diamond/TiC/SiC composites

Diamond-reinforced silicon carbide (Diamond/SiC) composites, with their exceptional thermal conductivity and mechanical properties, are considered ideal packaging materials for high-power-density and highly integrated electronic devices.However, their fabrication challenges and insufficient interfacial performance, particularly interfacial defects caused by acoustic and lattice mismatches, significantly limit further performance improvements.To address these issues, this study utilized stereolithography-based 3D printing technology to achieve rapid and precise material shaping, combined with magnetron sputtering to introduce a Ti layer, followed by reactive infiltration to fabricate Diamond/TiC/SiC composites.Advanced characterization techniques, including scanning electron microscopy, transmission electron microscopy, and energy-dispersive spectroscopy, were employed to systematically analyze the effect of TiC interlayer thickness on the interfacial structure and composite performance.The results revealed that the introduction of the TiC interlayer formed a quasi-coherent interface with good lattice matching between diamond and SiC, effectively reducing acoustic mismatch and interfacial dislocation density, thereby significantly enhancing interfacial performance.The thermal conductivity and flexural strength of the composites exhibited a trend of initial increase and subsequent decrease with increasing TiC interlayer thickness.When the TiC layer thickness reached 154 nm, the thermal conductivity and flexural strength achieved maximum values of 478 W/(mK) and 342 MPa, respectively, representing improvements of 14.6 % and 11.4 % compared to composites without the TiC interlayer.This study proposes a strategy to enhance the overall performance of composites by constructing quasi-coherent interfaces, optimizing interfacial bonding, and mitigating acoustic mismatch, providing valuable theoretical and technical guidance for the interfacial design of Diamond/SiC composites and the development of high-performance thermal management materials.