https://hal.archives-ouvertes.fr/hal-01556646/document

Fatigue crack initiation and growth in a CrMo steel under hydrogen pressure

GASTEF: The High Pressure Gas Tank Testing Facility of the European Commission Joint Research Centre

Fluence rate effects on irradiation embrittlement of model alloys

Irradiated for 4 cycles inside the reactor, the irradiation surveillance capsule (ISC) was withdrawn and transported to Nuclear Power Institute of China (NPIC) for dismantling in the hot cell. This paper presented tensile tests and Charpy-V impact tests on non-irradiated and irradiated specimens. Tensile tests were performed at room temperature and 300 °C respectively, and Charpy-V impact tests were performed at series temperatures. Instrumented impact curves and tensile curves were obtained and analyzed. Impact absorbed energy, lateral expansion and crystallinity transition curves were plotted by a hyperbolic tangent function. The irradiation-induced shift of transition temperature, upper shelf energy, tensile strength and yield strength were determined. And irradiation-embrittlement effect on RPV was evaluated by prediction and measurement of irradiation-induced transition temperature shift. Results showed that the parameters including neutron fluence and transition temperature were in normal range, and the next capsule could be withdrawn according to original irradiation monitoring program.Copyright © 2010 by ASME

Irradiation-Embrittlement of Reactor Pressure Vessel Steel

Evidence for chromium stabilisation of irradiation damage in RPV weld metals

Annealing of a reactor pressure vessel embrittled by neutron irradiation constitutes the only known technique to restore the initial material properties, to an extent that depends on the annealing conditions and on the materials. This technique is used in WWER-440 type reactor pressure vessels. A very important related issue is the one of re-embrittlement behaviour of the material after the annealing. In this respect, there is an obvious link with radiation embrittlement understanding. This report compiles the vast amount of information on annealing and re-embrittlement, which is available in the European countries where such annealing operations have been performed. In addition this topic was also investigated in various TACIS-PHARE projects, and the conclusions are included here as well. To complete the state-of-the-art, the results from a number of annealing experiments carried out in US on “Western” type RPV steels have also been considered. How to obtain EU publications Our priced publications are available from EU Bookshop (http://bookshop.europa.eu), where you can place an order with the sales agent of your choice. The Publications Office has a worldwide network of sales agents. You can obtain their contact details by sending a fax to (352) 29 29-42758. The mission of the JRC is to provide customer-driven scientific and technical support for the conception, development, implementation and monitoring of EU policies. As a service of the European Commission, the JRC functions as a reference centre of science and technology for the Union. Close to the policy-making process, it serves the common interest of the Member States, while being independent of special interests, whether private or national.

Annealing and Re-embrittlement of Reactor Pressure Vessel Materials - State of the Art Report

The three years European MATHRYCE project, dedicate d o material testing and design recommendations for components exposed to hydrogen enhanced fatigue, started in October 2012. Its main goal is to provide an “easy” to implement meth odology based on lab-scale experimental tests under hydrogen gas to assess the service life of a real scale component taking into account fatigue loading under hydrogen gas. Dedicated experimental tests will be developed for this purpose. In the present paper, the proposed approach is presented a d compared to the methodologies currently developed elsewhere in the world.

Material testing and design recommendations for components exposed to hydrogen enhanced fatigue – the mathryce project

Mechanistic Interpretation and Forecasting of Radiation Damage of High Ni RPV Materials Data

The integrity of the pressure vessel is vital to the safe operation of a nuclear reactor. It is therefore necessary to monitor or predict the changes in the reactor pressure vessel (RPV) material during operation. Exposure to irradiation (or elevated temperatures) causes the segregation of phosphorus to internal grain boundaries in RPV steels. This, in turn, encourages brittle intergranular failure of the material. The PISA project had the objective of reducing the uncertainties associated with the impact of this failure mechanism on the properties of the RPV, both during service and at the end-of-life. This report presents the experimental results on the segregation of P and C during irradiation and thermal treatments, and the associated mechanical property changes, generated within PISA. The new data cover a range of bulk P levels, irradiation temperatures and fluences, steel types and product forms. In all cases only modest increases of P level on the grain boundary have been observed in commercial steels. Segregation is higher in pre-strained than in unstrained material. In addition a model for P segregation under irradiation has been developed, and shown to be capable of fitting the experimentally observed changes in P level after irradiation. Significant insight into the development of the microstructure under irradiation has thereby been obtained. Overall, the data and modelling together indicated that relatively small amounts of segregation are likely to occur under most reactor operational conditions in homogeneous commercial steels, and an (unexpectedly) small amount of additional embrittlement likely to derive from this process during reactor service. How to obtain EU publications Our priced publications are available from EU Bookshop (http://bookshop.europa.eu), where you can place an order with the sales agent of your choice. The Publications Office has a worldwide network of sales agents. You can obtain their contact details by sending a fax to (352) 29 29-42758. The mission of the JRC is to provide customer-driven scientific and technical support for the conception, development, implementation and monitoring of EU policies. As a service of the European Commission, the JRC functions as a reference centre of science and technology for the Union. Close to the policy-making process, it serves the common interest of the Member States, while being independent of special interests, whether private or national.

/pdf/project-pisa-phosphorus-influence-on-steel-ageing-ew2590gqvj.pdf

Acosta Iborra Beatriz

Papers

Annealing and Re-embrittlement of Reactor Pressure Vessel Materials - State of the Art Report

Material testing and design recommendations for components exposed to hydrogen enhanced fatigue – the mathryce project

Mechanistic Interpretation and Forecasting of Radiation Damage of High Ni RPV Materials Data

Project PISA: Phosphorus Influence on Steel Ageing

Uncertainties Related to the Surveillance Programmes of RPV and their Impact on Lifetime Management