Understanding pressure vessel steels: An atom probe perspective

A review of the contributions of the atom probe field-ion microscopy (APFIM ) technique to the microstructural characterization of pressure vessel stee ls and to the understanding of the embrittlement of these materials during neutron irradiation is presented. Atom probe studies have revealed that the microstructure contains a variety of ultrafine clusters and precipitates s ome of which are only formed during neutron irradiation. Furthermore, there is a complex pattern of segregation of various solutes (including phosphor us, nickel, manganese, or molybdenum) to grain boundaries in some pressure vessel materials, and there may also be additional intergranular precipitat ion in these materials. Published by Elsevier Science inc.