Atom Probe Studies of the Nanochemistry of Steels

Abstract Steels represent by far the most widely used class of engineering alloys, and comprise almost 95% of total world metal production. Yet despite their familiarity and ubiquitous distribution, many fundamental questions remain unanswered regarding the nature of the solid state chemical reactions occurring during the heat treatment of steels, the mechanisms by which alloy additions affect the kinetics of these processes, and the role of trace impurities on properties. The difficulties involved in studying such processes experimentally arise from two main sources. Firstly, the effects involved are often on an extremely fine scale. Secondly, one of the key elements involved is carbon, which is extremely difficult to study by conventional microanalytical techniques. Remarkable progress has been achieved in these areas through the application of the atom probe method. Much of this work has been reviewed in a recent monograph by Miller et al.