Materials Science on the Atomic Scale with the 3-D Atom Probe
08 Nov 2006 | Online Presentations | Contributor(s): George D. W. Smith
Some of the key goals of materials science and technology are to be able to design a material from first principles, to predict its behaviour, and also to optimise the processing route for its manufacture. In recent years, these goals have come closer to realisation, thanks in part to the introduction of the three dimensional atom probe (3DAP). This instrument permits the real-space experimental reconstruction of the positions and identities of the individual atoms in a solid specimen. The 3DAP has revealed a huge amount of new information about the atomic-scale structure and composition of materials. It has also provided a unique "bridge" between experiment and theory. For the first time, it has been possible to benchmark 3-D atomistic computer models, by inserting atomistic data from real experiments. This has greatly enhanced the value of the models, and improved the level of confidence that materials users place upon them. Three case studies will be used to illustrate this new approach to materials design: the nucleation of precipitates in aluminum alloys; the long-term thermal evolution of second phases in steels; and the development of improved processing routes for making multilayer thin film GMR read head devices for computer hard discs.