In-situ deposition of diamond on functionally graded copper scaffold for improved thermal conductivity and mechanical properties

Abstract

A novel functionally graded structure of diamond was developed with significantly enhanced thermal conductivity and compressive strength, based on synergistic effects combining chemical vapor deposition (CVD) and selective laser melting (SLM). In-situ diamond growth was achieved without conventionally complex pretreatment steps thanks to the high surface roughness of as-printed graded copper scaffold. The continuous diamond film coated on graded copper scaffold forms a monolith with interconnected network, acting as an effective layer for heat conduction with an exceptional increase (459%) in thermal conductivity compared with copper counterpart. The functionally graded structure also demonstrates a progressive mechanical response to loading compared with the uniform structure. This work opens a new avenue for realizing three-dimensional diamond structure and proves its multifunctionalities, especially for high-power electronics applications.