Materials related R and D work for the ESS target stations

Current planning for the European Spallation Neutron Source Project (ESS) provides for two target stations of 5 MW beam power each: a long pulse station (2 ms, 162/3 Hz) and a short pulse station (1.4 μs, 50 Hz). In both target stations liquid mercury is the reference target material. Materials related R and D work concentrates on: - The effects of the high pulsed power input into the short pulse target (stress pulses, pitting, high cycle fatigue) and their mitigation (with emphasis on the introduction of bubbles of non-condensable gas in the liquid metal). - The effects of radiation on the mechanical properties of structural target components (hardening and embrittlement). - Investigations of novel cryogenic moderator materials (ice and solid organic compounds) under fast neutron irradiation. Most of these efforts are carried out together with other projects within international collaborations such as ASTE, JESSICA, LiSoR, STIP, URAM and others