Critical analysis of the mini-CT geometry for fracture toughness characterization of the 73W high-copper submerged-arc weld in the unirradiated and irradiated condition

Research outputpeer-review


Fracture toughness measurement using miniaturized specimens such as the mini-CT is gaining a lot of acceptance worldwide. This was recently acknowledged by the multiple organizations participating to the EU H2020 FRACTESUS project that SCK CEN is coordinating. One of the key materials used within this project and that will serve as a benchmarking material is the 73W weld of the 5th HSSI program performed at ORNL in the late 90′s for an extensive well-controlled characterization in both unirradiated and irradiated condition. From the remaining broken specimens, a large number of mini-CT specimens were fabricated and tested. This paper addresses a number of key questions, among which the effect of geometry, testing conditions and master curve evaluation as compared to the original data obtained on large CT specimens at ORNL. The test results are analyzed for master curve evaluation according to the ASTM E1921-22 standard and further discussed to assess the applicability of this mini-CT geometry as an irradiation damage metrics but also for evaluating the lower bound fracture toughness curve.

Original languageEnglish
Article number109929
Number of pages25
JournalEngineering Fracture Mechanics
StatePublished - Mar 2024


This research received funding from the European research and training programme 2020-2024 under grant agreement No 900014 (H2020 FRACTESUS). The views and opinions expressed herein do not necessarily reflect those of the European Commission. The 73W weld material was kindly provided by ORNL. The authors are indebted to Tomasz Brynk (1983-2022) who contributed to this project and to whom this work is dedicated. Many thanks to Meng Li, former PhD student, who performed the finite element calculations and to Giovanni Bonny and Inge Uytdenhouwen, respectively project manager and program manager, for their support.

FundersFunder number
Horizon Europe900014
ORNL - Oak Ridge National Laboratory
Horizon Europe

    ASJC Scopus subject areas

    • General Materials Science
    • Mechanics of Materials
    • Mechanical Engineering

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