View/Open - Scholarly Commons Home

two properties of glass fiber reinforced ABS filaments were improved by adding a
small amount of compatibilizer and plasticizer.
In attempts to improve the property of materials to be used by FDM process, Iron /
nylon mixture consisting of iron metal particles in a p301 mixture was selected by
Masood, S.H et al [8] The reason for using iron in the composite mixture was for its
reasonably good mechanical and thermal properties and its capabilities of mixing
and surface binding with polymers. Three samples of composite materials consisting
of iron particles of given volume and a specific particle size were mixed in the matrix
of nylon (p301) material. The first sample consisted of 70% nylon and 30% iron by
volume with particle size 50-80lm. The second sample consists of 60% nylon and
40% iron with particle size of 50-80lm. The third sample consists of 60% nylon and
40% iron with particle size less than 30 μm. The filaments were made and each type
of filament made was tested for its tensile properties. It was found that the variation
of modulus of elasticity and tensile strength and tensile elongation of composites
were strongly dependent upon the varying size of metal particles.
To investigate the use of medical-grade polymethylmethacrylate (PMMA) in fused
deposition modelling (FDM) and to fabricate porous customized freeform structures
for several applications including craniofacial reconstruction and orthopaedic
spacers, an experiment was conducted by David et al [9]. It was found that a liquefier
and envelope temperature of 235 C and 55 C, respectively, as well as increasing the
model feed rate by 60 percent, were necessary consistently extrude the PMMA
filament. Structures with different porosities and fabrication conditions were
produced, and their compressive mechanical properties were examined. Results
showed that both the tip wipe frequency and layer orientation used to fabricate the
structures, as well as the porosity of the structure had an effect on the mechanical
properties.
In another research project by Iwan et al [10], a bioresorbable polymer poly(e-
caprolactone) (PCL) was developed as a filament modeling material to produce
porous scaffolds, made of layers of directionally aligned microfilaments, using this
computer-controlled extrusion and deposition process. Porous FDM scaffolds were
made of layers of directionally aligned microfilaments within a geometrical 3D
30