Abstract |
In the presented work, Multiphoton Lithography (MPL) was used to fabricate 3D mechanical
metamaterials in the μm scale. MPL is a well-established fabrication method, capable of creating
microstructures with a resolution exceeding a few decades nm. The mechanical response of the
metamaterials was later measured with nano-Dynamic Mechanical Analysis (nano-DMA). NanoDMA is an emerging technology that can perform accurate nanoscale characterization of a
material’s mechanical properties. Additionally, the deformation of the microstructures is
observed and recorded real-time with a Quanta 3D FEG. For the first time to our knowledge, the
mechanical properties of the photopolymerizable resin used in MPL are properly characterized.
Loss and Storage modulus, Hardness and Poisson’s ratio were thoroughly and accurately
determined as a function of laser power. The investigated microstructures, which include the
infamous ‘bowtie’, truss-like octahedra structures, the re-entrant triangular geometry, a
pioneered rotating structure and a stent with auxetic properties, are a few μm in size. Mechanical
metamaterials have numerous potential applications in medicine, biology, electronics,
infrastructure and aerospace. They possess superior durability and vibration absorption which
can be employed in body and seismic protection. Their porous and unique architecture often
resembles that of bones or other body parts, which makes them prime candidates for bone or
tissue engineering. The counter-intuitive motion of negative Poison’s ratio can be used in stents,
tunable filters and precise actuators.
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