Evaluations of the Irwin. beta. /sub Ic/ adjustment for small specimen fracture toughness data

Conference · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5642263

Merkle, J G

When small specimens are used to measure the cleavage fracture toughness of pressure vessel steels in the transition range of temperature, specimen thickness size effects and large amounts of data scatter are often observed. The size effects are manifested by an increase in the average value of fracture toughness with decreasing specimen thickness, eventually resulting in a change in fracture mode from cleavage to ductile tearing. It has been shown that a semiempirical adjustment for the interacting effects of specimen thickness, yield stress and toughness originally proposed by Irwin is capable of reducing the calculated values of toughness and data scatter to levels consistent with large specimen test data. This is true for dynamic as well as for static initiation toughness values. The nature of the size effect described by the Irwin ..beta../sub Ic/ equation is illustrated and specific cases are shown in which ..beta../sub Ic/ adjustment has eliminated size effects, for both static and dynamic fracture toughness data.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5642263
• Report Number(s): CONF-8310143-57; ON: DE84003292
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200* -- Nuclear Reactor Technology-- Components & Accessories
ALLOYS
CLEAVAGE
CONTAINERS
CRACKS
CRYSTAL STRUCTURE
DATA ANALYSIS
DIMENSIONS
FRACTURE PROPERTIES
IRON ALLOYS
IRON BASE ALLOYS
MECHANICAL PROPERTIES
MICROSTRUCTURE
PLATES
PRESSURE VESSELS
STEELS
STRESSES
THERMAL SHOCK
THICKNESS
YIELD STRENGTH