Resumo (PT):
Abstract (EN):
Fused Deposition modeling (FDM) became one of the most influential processes of the last decade. The process has continuously evolved, and nowadays is common and easily available. FDM is available for two different sectors: the professional, with expensive machines conceived for high volume productions, high precision and high performance. On the other hand, low cost machines have been flooding the market since the patent expired. Initially, these machines were flimsy, unreliable and limited to one or two types of feedstock. Currently, the offer is vast, with friendly and cheaply available machines, and filaments from common usage polymers to high performance polymers and composites. This evolution in the process led to the employment of the technology in several areas, from the simple hobbyist to engineering applications. However, the emergence to improve the properties and performance of the printed parts, turn the process adequate for final/consumer parts. Consequently, the mechanical properties have a major role in the selection of the process (allied to the low cost of the machines and filaments). This work focuses on the study of FDM mechanical properties of printed parts and how they change with simple layer filling features. For this study, three types of PA filaments were selected: PA6, and PA12 with and without short carbon fibers. In a first stage, the mechanical properties of the raw material were determined (filament form) in order to understand the material behavior. On a second stage, dogbone test samples were produced with 100% infill, varying the number of perimeters, the printing starting point in the part, and the orientation of the sample in the printing bed (xy – on flat, xz – on edge). The results obtained confirm the anisotropy of the process, revealing distinct properties for each feature tested and exposing the most sensitive parameter and, hence, a critical factor. As expected, mechanical properties increased with number of layers and/or perimeters. This study aims to contribute to the creation of a correct strategy for the material deposition in order to sustain localized mechanical solicitations.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
24