ABSTRACT
The embrittlement of nuclear reactor pressure vessels as a consequence of neutron irradiation has at least three components. One of these is known simply as 'matrix damage' and is believed to be due to point defect clusters, probably associated with minor alloying or impurity atoms [1]. Such features are currently beyond the direct imaging capability of TEM but they are amenable to investigation by indirect methods in bulk samples. However, if a high density of such features is present then it is feasible that they could affect electron absorption in the TEM and, consequently, influence the contrast of features such as thickness fringes and bend contours. TEM could then be used to quantify variations in damage on a local level. The aim of this experiment was to explore the possibility of detecting and quantifying electron irradiation damage, induced directly in the TEM, by measuring simple 2-beam absorption parameters.
