The study on the dependence of the neutron damage rate in Fe-Cu model alloy by means of 3DAP method

Three dimension atom probe (3DAP) is an experimental method to test distribution of two dimensional atoms at an area with about some tens nm in surface diameter of specimen by combining a field ion microscope and a position-sensitive type detector and to measure three dimensional concentration distribution of an atom by extending this to its depth direction. In this study, by using Fe-0.6wt%Cu for a model alloy of reactor pressure vessel steel, damage rate which is one of radiation parameters was focussed, to investigate its effect on damage texture, especially clustering of Cu. As a result, it was found that lower rate showed more transfer numbers of point defect, of which tendency agreed with a result of model computation. This was thought by that magnitude of sink effect against the point defect depended on the damage rate. (G.K.)