Session: CS-36-01 Combined Session: Master Curve Method and Applications, and Improvement of Flaw Characterization Rules for Fitness for Service

Paper Number: 62040

Start Time: Thursday, July 15, 2021, 09:00 AM

62040 - Determination of Eurofer97 Fracture Toughness by Testing Small C(T) Specimens 

The use of small specimens to determine mechanical properties of neutron irradiated materials has been studied over previous decades both in fission and fusion programs, but also to characterize and optimize new materials by nuclear and non-nuclear research communities. Currently a number of activities are running that focus on the standardization of the use of small specimens to determine fracture toughness properties for fusion reactor materials [IAEA CRP, EUROFUSION, F4E], and long term operation of LWR [CREIPI RR]. In fact the determination of the T0 reference temperature [ASTM E1921] has been successfully determined by testing small CT specimens (W=8mm, B=4 mm) of non-irradiated and irradiated reactor pressure vessel materials [PVP2014-28898, PVP2018-84950]. Fracture toughness data has already been produced in the transition region by testing small CT and bend specimen by a number of authors, but some concerns exist about the use of the Master Curve (MC) for ferritic/martensitic steels, not only by the use of SSTT but also by testing standard specimens as the 1TCT geometry. The main concern is the slope of the MC, that seems to be steeper than the standard one that is linked to the weak description of the observed scatter. In this paper, fracture toughness of EUROFER97 is obtained by testing small CT specimens with the geometry selected in IFMIF/DONES (W=9.2 mm, B=4.6 mm) in the transition region. Reference temperature T0 is determined and compared to the one obtained by testing 1/2TCT specimens. The scatter of the results is also assessed to validate the scatter description of the standard master curve.

Presenting Author: David Andres UKAEA

Authors:

David Andres UKAEA
Marta Serrano CIEMAT
Rebeca Hernandez CIEMAT
Yiqiang Wang UK Atomic Energy Authority
Mark Richardson United Kingdom Atomic Energy Authority