PSI - Issue 42

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

1245

7

35

35.0

27.5

30

27.5

30.0

25

21.9

25.0

21.9

20.4

20.4

20

20.0

15

15.0

10

10.0

Dimensions reduction [%] 5 i e si s re cti [ ]

5.0

0

0.0

X

Y

Z

X

Y

Z

Linear dimensions

Fig. 5. on the left the difference between the green part and the sintered tensile specimens is shown. The bar plot on the right shows the dimensional reduction percentage along each direction of the building platform . That was calculated as 100×(d g -d s )/d s for each direction, where d g indicates the value of a dimension in the green part (overall length, thickness, or gauge width) and d s the same dimension in the sintered part.

4.1. Tensile test results Three specimens were used to assess the tensile properties of the material using an Instron 8802 servohydraulic test machine. Three specimens printed and sintered with the same procedure were tested with a displacement ratio of 1 mm/min. The resulting stress-strain curves are shown in Fig. 6. The curves are representative of a ductile material, with a strain at failure of around 40%. The strain field was extrapolated using the DIC. The area reduction was found to be 30%. The fracture surface is shown in Fig. 7. In this figure, the pores left after the sintering process are still visible and they have an impact on the real load-bearing area.

Fig. 6. stress-strain curves obtained from tensile tests. Three tensile specimens labeled as Ti (i=1,2,3) were used to evaluate the repeatability of the tensile data.