PSI - Issue 79

Hiroshi Nishiguchi et al. / Procedia Structural Integrity 79 (2026) 517–523

520

Uncoated

Uncoated

Coated

Coated

Hydrogen release ratio (mass ppm/min)

Hydrogen release ratio (mass ppm/min)

Temperature ( o C)

Temperature ( o C)

(a)

(b)

Fig. 1. TDA profiles of SCM435 steel: (a) quenched and (b) quenched and tempered.

Table 3. Summarization of hydrogen content and hydrogen cut ratio.

Hydrogen content in base metal (mass ppm)

Ratio of hydrogen cut R H,C (%)

Material

Uncoated

Coated

① Quenched

0.76

1.01

0

S45C (Carbon steel)

② Quenched-Tempered

0.19

0.11

42.1

① Quenched

0.72

0.10

86.1

SCM435 (Low alloy steel)

② Quenched-Tempered

0.25

0.05

80.0

① Quenched

37.4

0.29

99.2

FC200 (Cast iron)

② Quenched-Tempered

50.9

4.25

91.7

SUS304 Solution-treated

2.55

0.07

97.3