2.3. Printing Parameters and Definition of a Work Plan

The general manufacturing parameters for the FDM printing of the specimens are presented in Table 3.

Manufacturing parameters with FDM printer BCN3D R19.

Due to the lack of specific standards for material characterization of FDM parts, as explained before, two different standards are going to be used for mechanical behavior testing: UNE 116005:2012 (based in ISO 527–2) [7] and ASTM D638-14:2014 [4]; the geometry of the specimens according to both standards is shown in Figure 5, where Type 1A and Type 1 are the geometries chosen for both standards, respectively.

Geometry of the specimens according to different international standards: (a) Type 1A: UNE 116005 [7]; (b) Type I: ASTM D638–14 [4].

As explained by Rodríguez-Panes et al. [26], the build orientation of the test specimen is one of the most influencing parameters on the mechanical properties of FDM parts. Figure 6a presents the three possible orientations, orientation 1 (flat) and 2 (on-edge) being the ones chosen in this work since orientation 3 is not appropriate for tensile testing due to the arrangement of the filaments perpendicular to the direction of the load. Figure 6b and c shows the two orientation of the samples used in this work.

(a) typical build orientation of the samples; (b) specimen printed with orientation 1; (c) specimen printed with orientation 2.

Five specimens for each orientation (1 and 2) are going to be tested according to either standard UNE 116005:2012 and ASTM D638–14:2014. A summary of the experimental work plan and nomenclature used in experiments is presented in Table 4.

The experimental work plan and nomenclature of the specimens.

Results from the experimental testing of specimens in Table 4 are going to be compared to those ones obtained ii [26] in specimens with non-solid infill; the material of the experiments was ABS (PrintedDreams) in blue and the test procedure according to standard ASTM D638–14:2014 with type I general usage test specimen. The aim is to observe the influence of the infill in the characterization of materials obtained by FDM and for validation purposes. A summary of the cases for comparison is gathered in Table 5.

Nomenclature of the specimens and printing parameters by Rodriguez-Panes et al. [26].