2020/12/01 by Callie I. Higgins, Higgins, Callie I., Tobin E. Brown +3
Engineering · #3D Printing in Biomedical Research #Additive Manufacturing and 3D Printing Technologies #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Nanofabrication and Lithography Techniques
paper · pdf · doi:10.48550/arxiv.2012.00496
openalex publication_date 2020/12/01 · openalex created_date 2022/07/25 · openalex updated_date 2026/07/28
Stereolithography (SLA) and digital light processing (DLP) are powerful\nadditive manufacturing techniques that address a wide range of applications\nincluding regenerative medicine, prototyping, and manufacturing. Unfortunately,\nthese printing processes introduce micrometer-scale anisotropic inhomogeneities\ndue to the resin absorptivity, diffusivity, reaction kinetics, and swelling\nduring the requisite photoexposure. Previously, it has not been possible to\ncharacterize high-resolution mechanical heterogeneity as it develops during the\nprinting process. By combining DLP 3D printing with atomic force microscopy in\na hybrid instrument, heterogeneity of a single, in situ printed voxel is\ncharacterized. Here, we describe the instrument and demonstrate three\nmodalities for characterizing voxels during and after printing. Sensing\nModality I maps the mechanical properties of just-printed, resin-immersed\nvoxels, providing the framework to study the relationships between voxel sizes,\nprint exposure parameters, and voxel-voxel interactions. Modality II captures\nthe nanometric, in situ working curve and is the first demonstration of in situ\ncure depth measurement. Modality III dynamically senses local rheological\nchanges in the resin by monitoring the viscoelastic damping coefficient of the\nresin during patterning. Overall, this instrument equips researchers with a\ntool to develop rich insight into resin development, process optimization, and\nfundamental printing limits.\n