Effects of the In Situ Growth of CNTs on Ti-Coated Diamond Surfaces on the Mechanical Properties of Diamond/Aluminum Composites

Diamond/aluminum composites have attracted significant attention as novel thermal management materials, with their interfacial bonding state and configuration playing a crucial role in determining their thermal conductivity and mechanical properties. The present work aims to evaluate the bending strength and thermal conductivity of CNT-modified Ti-coated diamond/aluminum composites with multi-scale structures. The Fe catalyst was encapsulated on the surface of Ti-coated diamond particles using the solution impregnation method, and CNTs were grown in situ on the surface of Ti-coated diamond particles using the plasma-enhanced chemical vapor deposition (PECVD) method. We investigated the influence of interface structure on the thermal conductivity and mechanical properties of diamond/aluminum composites. The results show that the CNT-modified Ti-coated diamond/aluminum composite exhibits excellent bending strength, reaching up to 281 MPa, compared to uncoated diamond/aluminum composites and Ti-coated diamond/aluminum composites. The selective bonding between diamond and aluminum was improved by the interfacial reaction between Ti and diamond particles, as well as between CNT and Al. This led to the enhanced mechanical properties of Ti-coated diamond/aluminum composites while maintaining acceptable thermal conductivity. This work provides insights into the interface’s configuration design and the performance optimization of diamond/metal composites for thermal management.