PSI - Issue 42

Saveria Spiller et al. / Procedia Structural Integrity 42 (2022) 1239–1248 Saveria Spiller/ Structural Integrity Procedia 00 (2019) 000 – 000

1246

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Fig. 7. the fracture surface of the tensile specimen with a magnified presentation of a typical internal defect;

In Table 2 the tensile properties are compared with the results of two other studies on SS 316L (Gong et al., 2019; Liu et al., 2020), which show good consistency. The last row of Table 2 reports the mechanical properties of a conventional SS 316L: both strength and elongation at fracture appear to be more elevated. Nevertheless, the results of the present study suggest that further investigation of this technique is desirable since the quality of the print can be improved to move closer to the conventionally processed 316L specimens.

Table 2: tensile properties of the specimens fabricated in the present work compared with similar works

σ y [MPa]

UTS [MPa]

E [GPa]

ε %

T1 T2 T3

161 142 139 194 167 205

473 443 441 441 465 515

172 203 192 152 193 --

37% 46% 42%

Liu et al. 2019 Gong et al. 2018

29.5% 31%

AISI SS 316L ( ASM Material Data Sheet )

60%

5. Conclusion Metal Extrusion Additive manufacturing was successfully used to print tensile specimens out of a highly filled polymer including dispersed 316L SS metal powder. The result of the printing procedure was satisfying since a good surface quality was obtained. Nevertheless, the tensile test results indicated a need for improvement of the fabrication process to achieve components of similar mechanical properties compared to the conventional material. The tensile tests gave a stress-strain curve in good agreement with other similar works, but the strength of the specimen is lower in comparison to conventional 316L specimens. One of the main issues encountered regards the porosity, therefore a greater effort should be made to improve the density of the specimens. The printing process and the post-processing need to be calibrated properly to achieve this result since both contribute to the creation of pores. Further investigations are required to characterize better the material and to further explore the potentiality of the technique. References Abel, J., Scheithauer, U., Janics, T., Hampel, S., Cano, S., Müller-Köhn, A., Günther, A., Kukla, C., & Moritz, T.