Reinforcement of thermally-conductive SiC/Al composite with 3D-inter-penetrated network structure by various SiC foam ceramic skeletons

In this paper, 3D-SiC network skeleton with different structures was successfully constructed by regulating the microstructure of SiC foam ceramic struts via polyurethane replication technology combined with reactive infiltration of Si and solid-state sintering. Then, SiC/Al composites with 3D-interpenetrated network structure (3D-SiC/Al) were fabricated via vacuum pressure infiltration of Al alloy into the 3D-SiC skeleton, for application as electronic packaging. The effects of different skeleton structures on the thermal conductivity (TC), coefficient of thermal expansion (CTE), and flexural strength of the composites were investigated in detail. Furthermore, representative volume element (RVE) models of the 3D-SiC/Al composites were developed and their heat transfer properties and dimensional stability were also comparatively analyzed by finite element (FE) simulations. The results showed that the 3D-SiC/Al composites exhibited high TC of 196 W/m.K, low CTE of 8.03 x 10(-6) K-1, and excellent flexural strength of 272 MPa. Low thermal deformation parameter (TDP) and Ashby map demonstrated that the synergistic effect of a complete 3D network skeleton and a clean well-bonded interface in the 3D-SiC/Al composites facilitated the integration of low CTE and high TC even at a low SiC content of 30 vol%. The FE results revealed a 63.5 % reduction in thermal stress and nearly an order of magnitude increase in heat flux for the RVE model of 3D-SiC (30 vol%)/Al composite compared to the RVE model of SiCP (60 vol%)/Al composite. This work provides a novel and scalable method for designing and synthesizing various composites for electronic packaging.

Automated summary

This study successfully constructed 3D-SiC network skeleton with different structures and fabricated SiC/Al composites with 3D-interpenetrated network structure, demonstrating high thermal conductivity and flexural strength.