Mechanical Couplings of 3D Lattice Materials Discovered by Micropolar Elasticity and Geometric Symmetry

Abstract Similar to Poisson’s effect, mechanical coupling is a directional indirect response by input loading. With the advance in manufacturing techniques of 3D complex geometry, architected materials with unit cells finite volume rather than point yield more degrees-of-freedom and foster exotic couplings such as axial–shear, axial–rotation, axial–bending, axial–twisting. However, most structural have been built ad hoc design without theoretical support elasticity, which does not provide general guidelines for couplings. Moreover, no comprehensive study all lattices symmetry operations has undertaken. Therefore, we construct decoupled micropolar elasticity tensor identify individual correlated groups. The tensors, classified 32 groups, 15 lattices. Our findings help solid potential applications various areas, including active metamaterials, sensors, actuators, elastic waveguides, acoustics.