Transition range drop tower J-R curve testing of A106 steel
Fracture toughness properties should be measured in the laboratory at loading rates and temperatures similar to those expected in the application of interest. This is not usually the case because of the experimental difficulties involved. This report describes a method being used to obtain J/sub IC/, J-R curves, and J at cleavage for three point bend tests conducted at drop tower rates through the ductile to brittle transition regime of the ferritic A106 steel being tested. The major conclusion is that these tests can now be accomplished, though a high degree of expertise and considerable practical experience is necessary to obtain good test results. The steel tested here is quite rate dependent as shown both by tensile tests and fracture toughness tests. A load elevation of 30 to 50% results in the drop tower 100 in/second tests on this material in comparison with static tests when both tests are conducted on the ductile upper shelf. Nonetheless, for this material J/sub IC/ and J-R curves are not elevated by the loading rate. This result corresponds to a tendency for crack initiation to occur at a smaller bend angle for the high rate tests than for the static tests and a correspondingly greater amount of crack extension in the rapid specimen at a given bend angle beyond crack initiation than is present in the static test.
- Research Organization:
- Naval Academy, Annapolis, MD; David W. Taylor Naval Ship Research and Development Center, Annapolis, MD (USA); Nuclear Regulatory Commission, Washington, DC (USA). Div. of Engineering Safety
- OSTI ID:
- 6730710
- Report Number(s):
- NUREG/CR-4818; ON: TI87900552
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
360103* -- Metals & Alloys-- Mechanical Properties
42 ENGINEERING
420500 -- Engineering-- Materials Testing
ALLOYS
CARBON STEELS
CRACKS
DUCTILE-BRITTLE TRANSITIONS
FRACTURE PROPERTIES
IMPACT TESTS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS TESTING
MECHANICAL PROPERTIES
MECHANICAL TESTS
STEEL-ASTM-A106
STEELS
TESTING