PSI - Issue 55

4

America Califano et al. / Procedia Structural Integrity 55 (2024) 201–205 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

204

Fig. 3. Tensile stress vs. strain curves for PMMA (a) and PC (b) dog-bone specimens printed with 0°, ± 45° and 90° printing patterns respectively.

Fig. 4. Flexural stress vs. strain curves for PMMA (a) and PC (b) rectangular specimens printed with 0°, ± 45° and 90° printing patterns respectively

Analysing the data from Tables 2 and 3 it can be noticed that the specimens characterized by the 90° printing pattern showed, in most cases, the highest standard deviation for all the considered mechanical properties. However, in general, it can be appreciated that the standard deviation for each mechanical property, for each printing setup and for each material was limited, thus witnessing the repeatability and the reliability of the printing process. Finally, it can be highlighted that the PC specimens had strengths that were almost 35% higher than the PMMA ones. Table 2. Mean value and standard deviation for the Young’s modulus E and the maximum stress S max obtained from the tensile tests of PMMA and PC specimens. Printing patterns E [MPa] S max [MPa] Mean Mean

Standard deviation

Standard deviation

0°

1977.8

72.84

37.5

1.19 1.96 0.46 1.19 1.96 0.46

PMMA

90°

1910

39.5 33.2

35.52 36.45

+/- 45°

1931.2 1977.8

0°

72.84

37.5

PC

90°

1910

39.5 33.2

35.52 36.45

+/- 45°

1931.2