Finite element prediction of effective elastic properties of interpenetrating phase composites with architectured 3D sheet reinforcements

• A new type of 3D interpenetrating phase composite (IPC) is introduced.
• Effective elastic properties are predicted using FEM.
• 3D triply periodic minimal surfaces are used as solid shell reinforcements in IPC.
• The effect of the architecture of 3D solid shell architectures is investigated.
• Manufacturability of the proposed IPC through 3D printing is shown.

In this paper, novel triply periodic minimal surfaces (TPMS) are converted into three-dimensional solid-sheet networks and used as reinforcements within a matrix material creating interpenetrating phase composites (IPC). Schwarz P (P), Schwarz D (D), Schwarz CLP (CLP), Schoen I-WP (IWP), Neovius C(P) (Neovius), Schoen G (Gyroid), Fischer and Koch S (S) TPMS architectures are investigated. The IPCs with the TPMS architectures are modeled using the finite element method, and their effective elastic properties (uniaxial, shear, and bulk moduli, anisotropy index, Poisson's ratio) are evaluated and compared with those of traditional composites (particulate and fibrous). The effects of the TPMS architecture, its volume fraction, and contrast in elastic properties between the two phases in the IPC are studied. Foam (cellular solid) is obtained if one of the phases in the proposed IPC is removed and its elastic properties are also estimated. It is shown that the TPMS architecture significantly affects effective elastic moduli when the contrast is high. The IWP-type IPC and foam give largest uniaxial and bulk moduli.