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on the mechanical properties and porosity of a scaffold structure made with ABS
plastic. With the help of Design of Experiments, these parameters were examined by
varying the main FDM parameters like build profile, raster width, air gap etc. A
number of samples were printed and compressive strength and modulus data were
collected. It was found that raster width and air gap were the most important
parameters effecting mechanical properties of the scaffold structures.
A study similar to the above investigation was carried out to study the mechanical
behaviour of ABS materials made with FDM processes. Jose et al [30] did this by
dividing the experimental studies in two parts – first by finding out the mechanical
properties of the feedstock material and the next by studying the mechanical
properties of ABS materials with different mesostructures. Tensile, torsional tests
were performed on the test specimens and it was found that the stress-strain
response had quite an effect due the mesostructural influence. Voids and loss of
molecular orientation during fused deposition extrusion were found to cause
reduction in strength with fused deposition processing.
3.5 Materials and Deposition
Testing of Materials
For printing parts with the Fab@home machine, a number of materials were tried
initially to check their response, flow rate, compatibility with the deposition style etc.
For printing a part in the Fab at home machine, a number of factors are to be
considered:
Speed of deposition
Granular size
Material feed rate
Path interval
Fluidity of the material
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