Printed Smart Devices on CelluloseBased Materials by means of AerosolJet Printing and Photonic Curing Printed electronics is an expanding research field that can reach the goal of reducing the environmental impact on electronics exploiting renewable and biodegradable materials, like paper. In our work, we designed and tested a new method for fabricating hybrid smart devices on cellulose substrates by aerosol jet printing (AJP) and photonic curing, also known as flash lamp annealing (FLA), capable to cure low temperature materials without any damage. Three different cellulosebased materials (chromatographic paper, photopaper, cardboard) were tested. Multilayer capability and SMDs (surface mount devices) interconnections are possible permitting high flexibility in the fabrication process. Electrical and geometrical tests were performed to analyze the behavior of printed samples. Resulted resistivities are 26.3 xc3x97 10xe2x88x928 xcexa9xe2x8bx85m on chromatographic paper, 22.3 xc3x97 10xe2x88x928 xcexa9xe2x8bx85m on photopaper and 13.1 xc3x97 10xe2x88x928 xcexa9xe2x8bx85m on cardboard. Profilometer and optical microscope evaluations were performed to state deposition quality and penetration of the ink in cellulose materials (thicknesses equal to 24.9, 28.5, and 51 xcexbcm respectively for chromatographic paper, photopaper, and cardboard). Furthermore, bending (only chromatographic paper did not reach the breakup) and damp environment tests (no significant variations in resistance) where performed. A final prototype of a complete functioning multilayer smart devices on cellulose 3Dsubstrate is shown, characterized by multilayers, capacitive sensors, SMDs interconnections.

Material characterization and precise finite element analysis of fiber reinforced thermoplastic composites for 4D printing Abstract   Fourdimensional (4D) printing, a new technology emerged from additive manufacturing (3D printing), is widely known for its capability of programming postfabrication shapechanging into artifacts. Fused deposition modeling (FDM)based 4D printing, in particular, uses thermoplastics to produce artifacts and requires computational analysis to assist the design processes of complex geometries. However, these artifacts are weak against structural loads, and the design quality can be limited by less accurate material models and numerical simulations. To address these issues, this paper propounds a composite structure design made of two materials  polylactic acid (PLA) and carbon fiber reinforced PLA (CFPLA)  to increase the structural strength of 4D printed artifacts and a workflow composed of several physical experiments and series of dynamic mechanical analysis (DMA) to characterize materials. We apply this workflow to 3D printed samples fabricated with different printed parameters to accurately characterize the materials and implement a sequential finite element analysis (FEA) to achieve accurate simulations. The accuracy of deformation induced by the triggering process is both computationally and experimentally verified with several creative design examples and is measured to be at least 95%, with a confidence interval of     (  0  .  972  ,  0  .  985  )    . We believe the presented workflow is essential to the combination of geometry, material mechanism and design, and has various potential applications.