定荷重フラクトグラフィ法による水素助長割れ特性の検討
1992 年 41 巻 468 号 p. 1422-1426
詳細
1992 年 41 巻 468 号 p. 1422-1426
The holding-load and fractographic (HLF) method proposed by the present authers was applied to hydrogen assisted cracking (HAC) test for five different heat-treated 2-1/4Cr-1Mo steels with different strength, and the effects of material strength and test condition on the threshold stress intensity factor KIH and fracture toughness KCH of hydrogen charged materials were discussed.
The KIH decreased with an increase in accumulated hydrogen density in a specimen and showed just a little dependence on the tensile strength. The KCH was shown to be independent of the hydrogen density and the amount of crack extension during the HAC test, and it approximately coincided with the fracture toughness KIC before hydrogen absorption. These results indicate the applicability of the HLF method to HAC test with high accuracy.
