The creep rupture behaviour of fast reactor steels, welds and transition joints in flowing sodium; a review of Cegb results

As part of a programme designed to investigate the behaviour of steels subjected to conditions typical of a sodium cooled fast breeder reactor, the CEGB has recently completed a six year programme of creep rupture testing in flowing sodium using a test facility designed and built at Marchwood Engineering Laboratories. The aim of the investigation was to use constant sodium purity and flow conditions to test a range of candidate fast reactor steels in various metallurgical states. Earlier work had suggested that sodium was most likely to have an effect when creep degradation processes are concentrated at grain boundaries (Fidler, 1980). Material states to investigate this process in a number of steels were included in the test programme. Each in-sodium creep rupture test was compared with an in-air test at the same temperature and stress