Thermo-electro-mechanical properties of interpenetrating phase composites with periodic architectured reinforcements

In this study, the multifunctional properties (thermal, electric, and mechanical properties) of a new type of three-dimensional (3D) periodic architectured interpenetrating phase composites (IPCs) are investigated computationally. These new IPCs are created using two interconnected, bicontinuous, and intertwined material phases. The inner reinforcing phase takes the shape of the 3D morphology (architecture) of the mathematically-known triply periodic minimal surfaces (TPMS). The TPMS reinforcements are 3D solid sheet networks with a certain volume fraction and architecture. The interconnectivity of the proposed TPMS-based IPCs provide a novel way of creating multifunctional composites with superior properties. In this study, the effect of six well-known TPMS architectures of various volume fractions on the thermal/electrical conductivity and Young’s modulus of the IPCs is investigated using the finite element analysis of a unit cell with periodic boundary conditions. The contrast effect (high and low) between the conductivities and Young’s modulus of the two phases is also investigated. The calculated effective properties are compared with some analytical bounds. The proposed TPMS-IPCs possess effective properties close to the upper Hashin-Shtrikman bounds. It is also shown that the effect of TPMS architecture decreases as the contrast decreases. Finally, the manufacturability of these new TPMS-IPCs is demonstrated through using 3D printing technology.