Mechanical Metamaterials Made by Photopolymerisation: Unit Cells, Boundary Effects, Nonlinearity and Qualification

Mechanical metamaterials derive performance from architecture, but photopolymerisation introduces dimensional error, boundary truncation and nonlinear constituent behaviour that can shift the apparent unit-cell response. ER-361 establishes a qualification route from as-built geometry to specimen-scale mechanics. Relative density, cell count and slenderness are linked to stiffness, instability and failure, while CT or optical metrology is paired with full-field deformation and force-displacement data. Cell-count and specimen-size sweeps expose boundary effects; geometric perturbations test sensitivity to manufacturing variation. The review therefore separates a transferable architectural response from behaviour that exists only for one specimen size, boundary condition or as-printed defect population.

ER-361.