Muhammad Hussam Khaliq, Rui Gomes, Célio Fernandes, João Nóbrega, Olga Sousa Carneiro and Luis Lima Ferrás
This work aims to provide additional insights regarding the practicability of using conventional materials in the fused filament fabrication (FFF) process.
Abstract
Purpose
This work aims to provide additional insights regarding the practicability of using conventional materials in the fused filament fabrication (FFF) process.
Design/methodology/approach
Two different acrylonitryle butadiene styrene (ABS) grades are studied and compared, aiming to check to what extent the regular ABS developed for conventional polymer processing, with a different rheology than the one provided for the FFF process, can also be used in this process (FFF).
Findings
The rheological results show that a general-purpose ABS (ABS-GP) melt is much more viscous and elastic than ABS-FFF. It is clear that using ABS-GP as feedstock material in the FFF process results in poor coalescence and adhesion between the extruded filaments, which has a detrimental effect on the mechanical properties of the printed specimens. Despite its lower performance, ABS-GP can be a good choice if the objective is to produce an aesthetical prototype. If the objective is to produce a functional prototype or a final part, its mechanical performance requirements will dictate the choice.
Originality/value
This work provides insightful information regarding the use of high viscosity materials on the 3D printing process.
Details
Keywords
Wagner de Campos Galuppo, Ana Magalhães, Luís Lima Ferrás, João Miguel Nóbrega and Célio Fernandes
The purpose of this paper is to develop new boundary conditions for simulating the injection molding process of polymer melts.
Abstract
Purpose
The purpose of this paper is to develop new boundary conditions for simulating the injection molding process of polymer melts.
Design/methodology/approach
The boundary conditions are derived and implemented to simulate real-life air vents (used to allow the air escape from the mold). The simulations are performed in the computational library OpenFOAM® by considering two different fluid models, namely, Newtonian and generalized Newtonian (Bird–Carreau model).
Findings
A detailed study on the accuracy of the solver interFoam for simulating the filling stage is presented, by considering simple geometries and adaptive mesh refinement. The verified code is then used to study the three-dimensional filling of a more complex geometry.
Originality/value
The results obtained showed that the numerical method is stable and allows one to model the filling process, simulating the real injection molding process.