Mechanical properties of periodic interpenetrating phase composites with novel architected microstructures

In this work, we investigate the mechanical properties of novel types of 3D printed interpenetrating phase composites (IPCs) with periodic architectures. IPCs are composites with co-continuous phases that interpenetrate each other in such a way that if one of the phases is removed the remaining phase will form a self-supporting cellular structure. The topology of the architected phase is based on the mathematically-known triply periodic minimal surfaces (TPMS) that minimize the effects of stress concentrations and provide better reinforcement. Here, computer added design (CAD) is employed to design the TPMS-based IPCs, then 3D printing technique was used to fabricate polymer-polymer two-phase IPCs using Polyjet 3D printing technology. The mechanical behavior of these printed IPCs is investigated under uniaxial compression. Results show that while the hard phase endures a larger fraction of the load, the softer phase confine cracks and prevent catastrophic failure. The IPCs follow a bending-dominated deformation behavior and are potential candidates for applications were damage toleration and vibration damping is a requirement.