Fracture Toughness Measurements at Elevated Loading Rates - SCK-CEN activities 2007 within ISO, ASTM and IAEA CRP-8 (topic area #2)

This report summarizes the activities performed in 2007 by SCK•CEN for the standardization of fracture toughness tests performed at loading rates higher than the quasistatic range presently envisaged by the ASTM E1921-05 standard. More specifically, investigations have been focused on impact toughness tests performed on precracked Charpy specimens using instrumented pendulums at loading rates in the order of 10^5 MPaVm/s. An account is given of SCK•CEN contributions to the relevant standardization activities currently in progress within both ASTM (subcommittee E08.08, revision of E1921 and E1820) and ISO (committee TC164/SC4F, preparation of a new test standard). Furthermore, an update is provided on the Coordinated Research Project Phase 8 (CRP-8) of IAEA, topic area #2 (loading rate effects). The most relevant updates are the completion of the round-robin exercise for the validation of Master Curve measurements on impact tested precracked Charpy specimens and an interlaboratory comparison of instrumented force measurements.