Macroporous diamond foam: A novel design of 3D interconnected heat conduction network for thermal management

Abstract

Diamond with a 3D porous macrostructure has a combination of outstanding intrinsic physicochemical properties and unique structural advantages, which is highly promising for wide-scale practical applications. In this paper, a novel macroscopic porous structure of diamond foam (DF) prepared by hot filament chemical vapor deposition (HFCVD) is proposed for thermal management. The continuous diamond film coated on macroporous Cu foam (CF) substrate forms a monolith of 3D interconnected diamond network, which can act as an effective conductive highway for heat transfer, leading to an exceptional thermal transport property significantly superior to that of CF. Then, DF was further infiltrated with epoxy resin as a thermal conducting filler through the vacuum impregnation process. The thermal conductivity of DF/epoxy composite significantly increased up to 10-fold from 0.23 (neat epoxy) to 2.28 W/m K even with a fairly low diamond loading of 1.2 wt%. The further finite element analysis indicates that the formation of 3D interconnected heat conduction network is advantageous to dissipate heat efficiently in practical application. This work opens up new opportunities toward realizing the application of macroporous DFs and their composites for the use in heat dissipation and the future development of high-performance thermal management systems.