Workshop on Ion Implantation as a Neutron Irradiation Analogue

Oxford, 26 - 28 September 2011

Ion Implantation is widely used as a (relatively) low-cost, rapid, means of introducing radiation damage in materials. Heavy ions (often self-ion, of the same atomic species as the main constituent of the alloys being tested) are used to introduce displacement damage, as are high-energy protons. Lower energy light ion (H, He) implantation can be used to simulate the effects of the production of these elements by transmutation. Several facilities worldwide can perform multiple simultaneous implantations (e.g. of self-ions and H and/or He), or can perform TEM in-situ studies of ion-irradiation. Ion-irradiated specimens, with a damaged layer typically less than 1µm deep, have been studied by TEM, atom-probe, etc., and it has recently become possible to perform “micromechanical” tests directly on ion –implanted materials.

Despite the convenience of these techniques, and the large number of studies carried out over many years using them, it is still unclear how the radiation damage thus produced is related to that produced by neutrons. There are very large differences between ion-irradiation and neutron irradiation in dose rates, damage densities and the subsequent balance between defect production, migration and annealing. As an increasing number of new materials are now being assessed for use in fission and fusion power generation, the use of ion-irradiation to assess their likely in-service behaviour is an important topical issue, which this workshop aimed to address.

This meeting was organised jointly with the Science & Technology Department of the French Embassy and Culham Centre for Fusion Energy, and was linked to the FEMaS-CA European Fusion Materials network. It was based on 14 keynote lectures (of ~ 1 hour) and substantial poster sessions where “work in progress” was reported. There was ample time for discussions centred around these. The workshop also included a visit to JET at CCFE Culham.

The meeting was low cost, so as to encourage participation from active research students and postdocs. Accommodation was at St Edmund Hall, one of the historic colleges of Oxford. Lectures and poster sessions were in Oxford University Engineering Department.