Investigating the mechanical response of microscale pantographic structures fabricated by multiphoton lithography

Abstract

The design of micromechanical devices that can facilitate large but recoverable deformations requires a mechanical behavior that embosoms hyperelasticity. While multiphoton lithography is the epitome of microscale fabrication, the employed materials demonstrate a linear elastic response accompanied by limited ductility. In this study, we investigate how this hindrance can be circumvented through the design of microscale pantographic structures. Pantographs possess riveting hyperelastic response inherited by their structural design, providing exorbitant reversible deformations. To prove the utility of pantographs in microscale design, finite element analysis simulations are performed to unravel the behavior of the structure as a function of its geometrical parameters. In addition, to evaluate the microscale modeling, specimens are fabricated with multiphoton lithography in a push to pull up configuration to accomplish in situ SEM microindentation tensile testing due to compression. Our findings are adduced to expound how the pantographic structures can embrace hyperelastic response even at the microscale, elucidating their feasibility for structural members in micromechanical devices that require reversible large deformations.