PSI - Issue 5

J. Belzunce et al. / Procedia Structural Integrity 5 (2017) 1275–1282 J.Belzunce et al./ Structural Integrity Procedia 00 (2017) 000 – 000

1281

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Table 2. Results of the fracture toughness tests using different displacement rates. Grade Test displacement rate [mm/min] J Q [kJ/m2]

J=C1 Δ a C2

EI JQ [%]

Hydrogen contents

C1

C2

Co  Cf (ppm) 0 (uncharged)

1 (Uncharged) 1 (H-charged) 0.1 (H-charged) 0.01 (H-charged) 1 (Uncharged) 0.1 (H-charged) 0.01 (H-charged) 1 (Uncharged) 1 (H-charged) 0.1 (H-charged) 0.01 (H-charged) 1 H-charged)

992 423 473 479 807 583 573 488 770 385 404 366

911 597 624 565 598 561 547 857 583 573 488

0.58 0.70 0.66 0.40 0.63 0.52 0.44 0.53 0.42 0.56 0.51 0.39

-

(a) 2.25Cr1Mo_690

57 52 52 52 51 67 49 48 52 - -

0.6  0.4 0.6  0.2 0.6  0.2 1.3  1.3 1.3  1.1 1.3  0.7 1.2  1.2 1.2  1.15 1.2  0.9

1020

0 (uncharged)

(b) 2.25Cr1Mo_600

0 (uncharged)

(c) 42CrMo4_700

K max [MPa· √ ] 372

Grade

Test displacement rate [mm/min]

J max (kJ/m2)

EI Jmax [%]

Hydrogen contents Co  Cf (ppm)

(d) 42CrMo4_500

0.1 (Uncharged) 0.1 (H-charged) 0.01 (H-charged)

401 110

-

0 (uncharged)

100

73 94

1.9  1.9 1.9  1.9

29

25

(a)

(b)

(d)

(c)

Fig. 6. Fracture surfaces of CT specimens (0.01mm/min). (a) 2.25Cr1Mo_600 uncharged, (b) 2.25Cr1Mo_600 hydrogen pre-charged (EI=67%) (c) 42CrMo4_700 uncharged, (d) 42CrMo4_700 hydrogen pre-charged (IH= 52%).