Mechanical testing of nuclear structural materials

Neutron irradiation leads to an increase in yield stress and an associated reduction of the fracture toughness called embrittlement. We operate hot cell labs for the testing of radioactive neutron-irradiated materials. Our fields of application are reactor pressure vessel steels and innovative materials for future nuclear applications, e.g. ferritic/martensitic steels, oxide-dispersion strengthened alloys and high entropy alloys. Limited availability of these materials raises our interest in small-specimen techniques.

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Methods

• Fracture mechanics testing with focus on miniaturized specimens
• Advanced SEM-based fractography to identify fracture-initiating microstructural features
• Small-punch and small-punch creep testing
• Standard mechanical tests (e.g. hardness, tensile test, Charpy impact test)
• Supporting finite element analyses

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Expertise

• Mechanical testing of neutron-irradiated/radioactive materials
• Small-specimen techniques for mechanical testing

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Highlights

• Systematic investigation of reactor pressure vessel material from the decommissioned Greifswald nuclear power plant

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Related projects

• Bruchmechanische Untersuchung von Reaktordruckbehaelterstaehlen mittels Kleinprobentechnik
  (Kleinproben, BMWi, Reactor Safety Research, 2019-2022)
• Untersuchungen zum Ausheilverhalten von Reaktordruckbehälterstählen bei niedrigen Temperaturen
  (WetAnnealing, BMWi, Reactor Safety Research, 2020-2025)
• Fracture mechanics testing of irradiated RPV steels by means of sub-sized specimens
  (FRACTESUS, EU, HORIZON 2020, 2020-2024)
• European Database for Multiscale Modelling of Radiation Damage
  (ENTENTE, EU, HORIZON 2020, 2020-2024)
• Structural Materials research for safe Long Term Operation of LWR NPPs
  (STRUMAT-LTO, EU, HORIZON 2020, 2020-2024)
• Innovative structural materials for fission and fusion
  (INNUMAT, EU, HORIZON EUROPE, 2022-2026)