STRUMAT-LTO aims to address the open issues in Reactor Pressure Vessel embrittlement research to support the safe Long Term Operation of European nuclear power plants.
structural materials for nuclear safety and longevity
STRUMAT-LTO is a Horizon 2020 project funded under H2020-Euratom-1 that will last 48 months from September 1, 2020 to August 31, 2024. Dr. Ákos Horváth, the general director of MTA-EK, together with Dr. Murthy Kolluri, a senior research consultant at NRG, coordinate the STRUMAT-LTO project. A total of 19 partners from 12 different countries will collaborate to enhance the safety, reliability and competitiveness of nuclear power plants (NPPs), and in turn, directly contribute to the European energy transition.

STRUMAT-LTO aims to fill research gaps concerning Reactor Pressure Vessel (RPV) embrittlement, one of the main causes hindering the Long Term Operation (LTO) of nuclear reactors by exploring ageing mechanism issues and validating existing prediction tools to ensure the safety and longevity of EU NPPs.

In order to better understand the mechanisms preventing the LTO of nuclear reactors, a variety of compositionally tailored RPV specimens irradiated to representative neutron fluences of interest for LTO (within Lyra-10 experiment in HFR Petten), will be used to study the impact of different elements causing the embrittlement.

Prediction tools, such as existing Embrittlement Trend Equations (ETEs) used to determine the durability and resistance of RPVs, will be assessed and validated based on new data generated from the project’s research on RPV behaviour in LTO conditions, as will surveillance testing methods and operating practices.

project organisation

STRUMAT-LTO’s activities are divided into 8 work packages (WP), each with milestones to achieve and deliverables to produce throughout the duration of the project.
Embrittlement behavior of RPV steels at high fluences
WP1 aims to generate RPV embrittlement data under conditions resembling those of a reactor operating over 60 years.
Assessment of small/sub-sized specimens testing methods
In WP2, test methods will be used to increase the amount of data concerning durability and resistance while also increasing testing reliability.
Synergetic effects of Ni, Mn, and Si on RPV embrittlement at high fluences
The goal of WP3 is to identify and explain the effects of chemical elements in terms of microstructural and mechanical changes occuring over time.
Validation of existing ETEs for LTO above 60 years
In WP4, test results from WP1, 2 & 3 regarding the effect of specific conditions and the chemical elements will be analysed in terms of their correlation and consistency with the existing Embrittlement Trend Equations (ETEs).
Assessment of MC approaches for high fluences
The goal of WP5 is to investigate the effect of long term operation conditions (i. e. high neutron fluences) on resulting scatter in fracture toughness results in the transition regime in order to assess validity of master curve (MC) approach under these conditions.
Dissemination of results & education and training
WP6 will communicate and disseminate project achievements and results to the research community, industrial stakeholders and the public while also providing a platform for education and training activities to support young researchers.
Project Management
WP7 aims to facilitate the execution of the project in order to achieve the set objectives within the pre-defined budget, time and quality plan by continuously monitoring project progress, identifying risks and employing necessary mitigation measures.
Ethics requirements
WP8 will ensure compliance with the project's ethics requirements.