Environmentally-assisted cracking behavior of a low-alloy steel under non-isothermal conditions

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:191340

James, L A ^[1]

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1. Westinghouse Electric Corp., West Mifflin, PA (United States)

The majority of experimental studies of environmentally-assisted cracking (EAC) behavior of low-alloy steels in elevated temperature aqueous environments are conducted under isothermal conditions. However, some structural applications may involve cyclic stresses that occur under non-isothermal conditions. This study involved the testing of a high-sulfur EAC-susceptible ASTM A302-B steel under conditions where the temperature cycled continuously between 149 C and 243 C. The temperature cycling was not in phase with the fatigue cycling. The testing commenced at conditions where this heat of A302-B exhibited EAC at 243 C, but not at 149 C. Crack growth rates were initially high, approximately equivalent to the EAC rates normally observed at 243 C, but over a fifty-seven day period of non-steady-state behavior, the crack growth rates steadily dropped to the non-EAC rates normally expected at 149 C. For the duration of the testing, crack growth rates under the non-isothermal cycling behaved as if the test was being conducted at 149 C. This experiment illustrates the complex non-steady-state EAC behavior that may be observed under non-isothermal conditions.

• DOE Contract Number: AC11-89PN38014
• OSTI ID: 191340
• Report Number(s): CONF-950740--; ISBN 0-7918-1337-1
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
36 MATERIALS SCIENCE
CRACK PROPAGATION
FATIGUE
REACTOR MATERIALS
STEEL-MNMO
SULFUR ADDITIONS
THERMAL CYCLING
WATER COOLED REACTORS