Miniature Compact Tension Specimens for Upper Shelf Fracture Toughness Measurements on RPV Steels

Enrico Lucon, Marc Scibetta

    Research outputpeer-review


    Miniature Compact Tension, MC(T), specimens (thickness B = 4.15 mm) have been recently investigated at SCK•CEN for measuring the fracture toughness of steels under fully ductile conditions (upper shelf regime). The first results of this assessment, made by comparison with results obtained from 1TC(T) samples of various RPV steels with quite different toughness properties, have been described in a previous paper by the same authors. It was observed that, although a systematic and significant underestimation of both critical toughness values and crack propagation resistance was observed for the MC(T) samples with respect to the bigger specimens, it is possible to establish an empirical correlation between the two geometries which allows deriving acceptable estimates of the material's critical toughness. In this work, further investigations are presented, related to: • the behaviour of MC(T) and 1TC(T) specimens in the crack tip blunting phase; • the role of work hardening in decreasing the tearing resistance of MC(T) specimens; • the use of alternative parameters (crack-tip opening displacement CTOD, crack-tip opening angle CTOA, Ernst's modified J-integral JM). Evidence is also presented which could justify a revision of the specimen measuring capacity (Jmax) in the current ASTM E1820-01 standard.
    Original languageEnglish
    Pages (from-to)1-10
    JournalJournal of ASTM International
    Issue number3
    StatePublished - Mar 2008
    EventASTM Small Specimen Symposium - ASTM, Anaheim
    Duration: 31 Jan 20071 Feb 2007

    Cite this