  Fused Deposition Modeling (FDM) is one of the most widely explored additive
manufacturing method that uses thermoplastic materials to manufacture products.
Mechanical properties of parts manufactured using FDM are influenced by
different process parameters involved during manufacturing as they impact the
bonding among different layers of cross-section. In this study, the effect of
infill patterns and build orientations on the mechanical properties of PLA
based parts manufactured using FDM method is studied. Six different infill
patterns (triangles, cubic, concentric, tetrahedral, lines, and zigzag) and
three different orientations (flatwise, edgewise, and upright) are considered
for rectangular beam type parts. For determining mechanical properties of parts
with different infill patterns and orientations, flexural bending test is
performed. Experimental modal analysis of manufactured parts is performed to
observe the relation of natural frequencies with elastic modulus of the parts
obtained from flexural bending test. The possibility of experimental modal
analysis as an alternative non-destructive method for testing mechanical
properties of FDM 3D printed parts is explored.
