Mechanical Behavior of Shape-Memory Alloy Triply Periodic Minimal Surface Foam Based on Schwarz Primitive

Abstract

This work investigated the effective structural and functional behavior of shape-memory alloy (SMA)-based triply periodic minimal surface foams based on the Schwarz primitive (P-foams) using finite-element analysis (FEA) and numerical homogenization methods. The effect of relative density and applied temperature on the homogenized mechanical behavior of the SMA foam, including its superelasticity, and the evolution of the effective martensite volume fraction with the applied load was investigated considering axial and shear loading cases. In contrast to dense SMA, the effective martensite volume fraction in the considered foam was found to vary exponentially with the strain in the case of monotonic loading, asymptotically approaching 1 as the strain increased indefinitely. Moreover, the effective superelasticity of the SMA P-foam was found to be facilitated by decreased temperature and relative density. The onset of phase transformation for the P-foam under various loading scenarios was shown to be well approximated using an extended Hill loading surface.