A comparison of the near-threshold corrosion fatigue crack propagation rates in Mil S-24645 HSLA Steel and its weld metal

Journal Article · Sat May 01 04:00:00 EDT 1993 · Journal of Offshore Mechanics and Arctic Engineering; (United States)

DOI:https://doi.org/10.1115/1.2920102· OSTI ID:5928719

Todd, J A; Chen, L; Yankov, E Y ^[1]; Tao, H ^[2]

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1. Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Metallurgical and Materials Engineering
2. Atlas Testing Labs., Inc., Los Angeles, CA (United States)

Near-threshold corrosion fatigue crack propagation studies have been conducted using compact tension specimens of Mil S-24645 HSLA steel and a compatible weld metal in air, ASTM seawater at the free corrosion potential, and ASTM seawater with [minus]0.8V and [minus]0.1V (SCE) cathodic protection. Tests were conducted at 10 Hz and a stress ratio, R = 0.1. The weld metal exhibited slower crack growth rates and higher threshold stress intensity ranges in both air and ASTM seawater than the base metal. However, the weld metal itself exhibited similar behavior in air, ASTM seawater and under cathodic protection, giving a threshold stress intensity range of 10 to 12.7 ksi in[sup 1/2] (11 to 14 MPa m[sup 1/2]). With the exception of the weld metal tested in air, after correction for crack closure, the effective threshold stress intensity range was reduced to the range 3.2 to 5.0 ksi in[sup 1/2] (3.5 to 5.5 MPa m[sup 1/2]). Metal wedges, approximately 5 to 10 [mu]m (1-2 grain sizes), which developed during the tests, were observed to contribute to crack closure in the [minus]1.0V (SCE) cathodically protected specimens.

• OSTI ID: 5928719
• Journal Information: Journal of Offshore Mechanics and Arctic Engineering; (United States), Journal Name: Journal of Offshore Mechanics and Arctic Engineering; (United States) Vol. 115:2; ISSN 0892-7219; ISSN JMOEEX
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420500 -- Engineering-- Materials Testing
423000* -- Engineering-- Marine Engineering-- (1980-)
ALLOYS
BUILDING MATERIALS
CATHODIC PROTECTION
CORROSION FATIGUE
CORROSION PROTECTION
CORROSION RESISTANT ALLOYS
CORROSIVE EFFECTS
CRACK PROPAGATION
FABRICATION
FATIGUE
FORCING FUNCTIONS
FRACTURE MECHANICS
FRACTURE PROPERTIES
FUNCTIONS
HYDROGEN COMPOUNDS
JOINING
JOINTS
MATERIALS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICS
OFFSHORE PLATFORMS
OXYGEN COMPOUNDS
RESPONSE FUNCTIONS
SEAWATER
STRESSES
TENSILE PROPERTIES
TESTING
WATER
WELDED JOINTS
WELDING