Abstract: Fused Deposition Modelling (FDM) is one of the additive manufacturing techniques that has become highly attractive in the industrial and academic sectors. However, parts fabricated through FDM are highly susceptible to geometrical defects such as warpage, shrinkage, and delamination that can severely affect their function. Among the thermoplastic polymer feedstock for FDM, semi-crystalline polymers are highly prone to part distortion due to polymer crystallization. In this study, the influence of FDM processing conditions such as chamber temperature and print bed temperature on the induced thermal residual stress and resulting warpage are investigated using 3D transient thermal model for a semi-crystalline polymer. The thermo-mechanical properties and the viscoelasticity of the polymer, as well as the crystallization physics which considers the crystallinity of the polymer, are coupled with the evolving temperature gradient of the print model. From the results it was observed that increasing the chamber temperature from 25 °C to 75 °C leads to a decrease of 3.3% residual stress and increase of 0.4% warpage, while decreasing bed temperature from 100 °C to 60 °C resulted in 27% increase in residual stress and a significant rise of 137% in warpage. The simulated warpage data are validated by comparing it with the measured warpage values of the samples using 3D scanning.
Abstract: Fused deposition modelling (FDM) is one of the most prominent rapid prototyping (RP) technologies which is being used to efficiently fabricate CAD 3D geometric models. However, the process is coupled with many drawbacks, of which the surface quality of the manufactured RP parts is among. Hence, studies relating to improving the surface roughness have been a key issue in the field of RP research. In this work, a technique of modelling the surface roughness in FDM is presented. Using experimentally measured surface roughness response of the FDM parts, an ANFIS prediction model was developed to obtain the surface roughness in the FDM parts using the main critical process parameters that affects the surface quality. The ANFIS model was validated and compared with experimental test results.
Abstract: Paper presents knowledge about types of test in area
of materials properties of selected methods of rapid prototyping
technologies. In today used rapid prototyping technologies for
production of models and final parts are used materials in initial state
as solid, liquid or powder material structure. In solid state are used
various forms such as pellets, wire or laminates. Basic range
materials include paper, nylon, wax, resins, metals and ceramics. In
Fused Deposition Modeling (FDM) rapid prototyping technology are
mainly used as basic materials ABS (Acrylonitrile Butadiene
Styrene), polyamide, polycarbonate, polyethylene and polypropylene.
For advanced FDM applications are used special materials as silicon
nitrate, PZT (Piezoceramic Material - Lead Zirconate Titanate),
aluminium oxide, hydroxypatite and stainless steel.