Glass Transition of ABS in 3D PrintingM. Rahman , N. R. Schott , L. K. Sadhu ,
 North South University, Dhaka, Bangladesh
 Department of Plastics Engineering, University of Massachusetts - Lowell, Lowell, MA, USA
 IRays Teknology Ltd., Dhaka, Bangladesh
In a commercial 3D printer head, plastic ribbon passes through a hot nozzle of an extruder to dispense liquid plastic droplets to construct the model. In this paper a 2D axisymmetric model of a 3D head is considered to study the secondary transition change from below the glass temperature to above the glass-transition temperature of ABS (Acrylonitrile Butadiene Styrene) using COMSOL Multiphysics® Software. The transition from the glassy to the molten state of ABS is modeled using the heat capacity model. A narrow secondary transition is observed during the glass-transition temperature.