PSI - Issue 13

Catrin M. Davies et al. / Procedia Structural Integrity 13 (2018) 1384–1389 Author name / Structural Integrity Procedia 00 (2018) 000 – 000

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Table 1. Charpy impact energy results.

Heat Treatment

Orientation Horizontal

Sample 1 Energy (J)

Sample 2 Energy (J)

Sample 3 Energy (J)

As-Built As-Built

60 22 27 54 20

62 24 24 64 17

- -

Vertical

700 °C 700 °C 900 °C 900 °C

Horizontal

104

100

95 44

Vertical

Horizontal

118

Vertical

31

Table 2. Hardness results.

Heat Treatment

Orientation Horizontal

Average Hardness

As-Built As-Built

216.1 ± 1.5 212.9 ± 3.3 197.2 ± 3.9 186.3 ± 2.9 181.6 ±2.3 185.3 ±2.0

Vertical

700 °C 700 °C 900 °C 900 °C

Horizontal

Vertical

Horizontal

Vertical

4.2. Fracture Tests The experimental load displacement curves of the tests on the SEN(B) fracture samples are shown in Fig. 6 and are compared to the 2-D plane stress and plane strain finite element analyses. The experimental curve attains a peak load which tends to decreases as crack growth is initiated in the sample. Note that no crack growth has been simulated in the FE analysis. For the horizontal samples, the experimental load displacement curve in the as-built Fig. 6(a) and 700 °C heat treated conditions Fig. 6(b), are very similar, which slightly higher peak loads being achieved in the as-built condition, which is expected to be due to the higher strength of the material in this condition. These peak loads are achieved at similar displacement values, indicating a similar value of fracture toughness in the material. Note that during load-up to peak load, the experimental data falls between plane stress and plane strain FE results, as expected.

(a)

(b)

As-built Horizontal

700 C Horizontal

(c)

(d)

As-built Vertical

700 C Vertical

Fig. 6: Comparison of the load-displacement curves from the Fe simulations and experimental fracture tests on SEN(B) samples built in vertical and horizontal orientations and in the as-built or heat treated to 700 °C conditions.