PSI - Issue 42

S. Lindqvist et al. / Procedia Structural Integrity 42 (2022) 42–49 Author name / Structural Integrity Procedia 00 (2019) 000–000

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7

1500

500 J-integral [kJ/m 2 ] 1000

25  C 100  C 200  C 300  C Thermal transient (from 300 to 25  C)

Red: start of cooling Black: Final measured J basic at  25  C

0 1 2 3 4 5 6 7 8 9 10 0

Crack growth,  a [mm]

Figure 6. Comparison of the isothermal J-R curves and the J-R curve resulting from the cooling thermal transient.

1200

900

300

J-R curve (normalization method) Temperature

300

800

1000

Temperature J-R curve, normalization method

250

700

250

800

J-integral [kJ/m 2 ] 300 400 500 600

J-integral [kJ/m 2 ]

200

100 Temperature [  C] 150 200

Temperature [  C]

600

150

145  C

240  C

 130  C

100

400

200

50

 240  C

200

50

100

0

0

0

-1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0

0.0

0.5

1.0

1.5

2.0

Crack growth,  a [mm]

Crack growth,  a [mm]

Figure 7. Comparison of the temperature and the effect on the shape of the J-R curve, for a) specimen 5.2 and b) specimen 5.3.

25  C 100  C 200  C 300  C

1500

1200

600 J-integral [kJ/m 2 ] 900

Specimen 5.2 Specimen 5.3

300

0

0

1

2

3

4

5

Crack growth,  a [mm]

Figure 8. Comparison of the isothermal J-R curves to the J-R curves obtained during a thermal transient and by applying the normalization method.