A Critical Review on Hazardous Chemical Emissions and Particle from Fused Decomposition Modelling (FDM) Machine Due to patent expiry of 3D Printing technology, the cost of 3D printer becomes affordable to the domestic, primary and secondary schools. The Fused Decomposition Modelling (FDM) is one of the most popular 3D printing technologies and different polymeric materials are available in the market. The Acrylonitrile Butadiene Styrene (ABS) and Polylactic AcidPolylactide (PLA) are the most commonly used materials due to lower cost. The FDM consists of printing head with a heater and nozzle. The plastic filament was melt due to high temperature. During the melting process, chemicals are evaporated from the filaments. The exact amount and compositions of hazardous chemical emission is not yet defined. Although the industrial standard, ANSICANUL 2904, was published on January 31, 2019, it only covers the technical requirements on a single 3D printer. In the paper, we will study the potential compositions of hazardous chemical emission from 3D printer and suggest a list of parameters to be measured in a school laboratories in order to protect students.

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.