A quick explicit algorithm reconstructing mechanical constitutive curve for 3D printed miniaturized specimen in uniaxial tensile test

The tensile property of 3D printed polymers is found to be both process-dependent and size-dependent. And therefore, to accurately characterize hundred-micron features made by stereolithography in applications like vascular stent, miniaturized specimens fabricated at the device-relevant dimensional scale using the same conditions are required. To achieve gage displacement measurement without introducing errors from physical contact, we developed a numerical algorithm based on a 1D mechanical model of the specimen in tensile process to estimate gage displacement from the total displacement measured via grip distance for miniaturized specimen and calculate the whole stain-stress curve from it. The algorithm has been thoroughly tested and validated through both experiment and FEM simulation, shows a maximum relative error under 6%. And the total wall time for each run only takes 3.034 seconds on a normal laptop. Its efficiency and accuracy indicate its potential in rapid characterizing new-developed polymers and help improve fine-feature devices.