LYRA and other projects on RPV steel embrittlement Study and mitigation ofthe AMES Network

Within the framework of the European Network Ageing Materials Evaluation an d Studies (AMES), a number of experimental works on RPV materials embrittle ment are carried out at the Institute for Advanced Materials (JAM) of the J oint Research Centre (JRC) of the European Commission (EC). The objectives of AMES are mainly the understanding of the property degradation phenomena of RPV western reference steels like JRQ and HSST, eastern RPV steels like 15X2MFA and 15H2X15, and annealing possibilities. In order to conduct a ver y high quality irradiation programme, an AMES dedicated irradiation rig, LY RA facility, has been designed and developed at the high flux reactor (HFR) Petten. Another dedicated rig, named LIMA, has been developed at the HFR P etten in order to irradiate RPV steels, internals and in-core materials und er typical BWR/PWR conditions. The samples can be irradiated in pressurised water up to 160 bar, 320 degrees C, and the water chemistry fully controll ed. For irradiation of standard or miniaturised LWR related materials sampl es, another group of well experienced irradiation devices with inert gas or liquid metals environment are employed. These devices are tailored to thei r various specific applications. This paper is intended to give information about the structure and the objectives of the existing European network AM ES, and to present the various AMES main and spin-off projects, including a brief description on the modelling activities related to RPV materials emb rittlement. (C) 2000 Elsevier Science S.A. All rights reserved.