An extensive delayed-failure test of high-strength structural bolts has been conducted using actual structural joints. After about six years of exposure, one failure was experienced for bolts with the tensile strength as high as 1278 MN m−2. An approximate fracture-mechanics analysis was found to predict critical pit depths for the onset of delayedfailure. Detailed fractographic studies of the fracture surface revealed the localized non-cleavage transgranular fracture mode typical of hydrogen-assisted cracking of high-strength martensitic steels.
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References
1.
BOYDW. K. and HYLERW. S. :Proc. Am. Soc. Civil Eng.(J. Structural Div.), 1973, 99, (ST7), 1571.
2.
ITOUT. and ABEYAMAS.: Denki Seikou, 1972, 43, (1), 27.
3.
YAMAKIT.: Kyouryou-to-Kiso, 1970,4, (10), 18.
4.
KANAOM.et al.: JSSC, 1979, 15, (158), I.
5.
NAKASATOF. and OHNOT.: Tetsu-to-Hagané, 1976, 62, (1), 82.
6.
BEACHEMC. D.: Metall. Trans., 1972, 3,437.
7.
OHTANIH., TERASAKLF. and KUNITAKET.: Trans. Iron Steel Inst. Jpn, 1972, 12, 118.
8.
TERASAKIF. and NAKASATOF.: ‘Proc. of conf. On mechanism of delayed fracture caused by hydrogen’, 165 (in Japanese); 1975, Tokyo, Japan Institute of Metals et al.
9.
THOMPSONA. W. and CHESNUTTJ. C.: Metall. Trans., 1979, 10A, 1193.
