A predictive model for interfacial thermal conductance in surface metallized diamond aluminum matrix composites

As promising thermal management materials with tailored thermal expansion and light weight, diamond/aluminum composites have not exhibited desirable thermal conductivity (TC) yet, due to poor interfacial thermal conductance (ITC) between diamond and aluminum. Although some experimental studies have been made to improve the ITC by means of diamond surface metallization, there are no systematic theoretical evaluations of the influences of interface layers’ structures on the ITC yet. In terms of the components of diamond/Al interface layer, a carbide–metal–intermetallic, multi-layered interface model was established in this work, and the effects of different components and structures of interface layers on the ITC and TC of the surface metallized diamond/Al composites were predicted. The calculated results indicate that, basically, an interface layer of nanoscale thickness with high TC and large sound velocity is desirable to achieve high ITC. Under this premise, W and Mo interface layers are proposed to be the most promising candidates to improve the thermal performance of diamond/Al composites.