Enhanced thermal conductivity in low-cost diamond micro-powder/copper composites through Cr3C2 interfacial design

In response to the growing demand for low-cost, thin-flake, thermal technology of the third-generation management materials, diamond-copper alloys are gaining attention in scientific studies. Among these, diamond micro-powder-based composites offer a promising solution by addressing cost challenges and enabling the fabrication of thinner materials. This study explores the preparation of a chromium carbide (Cr 3 C 2 ) layer deposited onto diamond micro-powder via the molten salt technique, with diamond micro-powder and chromium powder as raw materials. The coating quality as well as the Cr 3 C 2 layer thickness were fine-tuned through adjustments to the molar proportion between diamond micro-powder and chromium powder. The best results were achieved at a molar ratio of 100/4.5, yielding a Cr 3 C 2 layer approximately 180 nm thick. Microstructural analysis revealed that the Cr 3 C 2 layer markedly strengthened the interface adhesion linking diamond micro-powder with copper, while enhancing the wettability of the two materials. At the optimal molar ratio of 100/4.5, the highest thermal conductivity of 431 W·m −1 ·K −1 was achieved. Finite element analysis and real-world application tests further validated the exceptional heat conductivity of the diamond-based composites, confirming their suitability for heat dissipation in electronic packaging applications. This research offers important perspectives on the development of diamond-copper composites with reduced thickness and lighter weight, advancing their application in thermal management solutions.