Investigation of phase decomposition in alloys with the tomographic atom probe

Atom probe field-ion microscopy (APFIM) has been established as a sensitive analytical method for the investigation of the local chemical composition on nanometer scales. The adaptation and operation of a position sensitive detection system to the APFIM, named tomographic atom probe (TAP), improve substantially the quantitative character of analysis with this method. The TAP provides spatially resolved information on the position in real space and chemical nature of each collected atom of the sampled volume. The extended set of data collected by the TAP can be treated with special visualizing tools. Three-dimensional images are created, which include all the information on microstructure and chemical composition of the sampled volume with atomic resolution. This paper demonstrates the capability of the TAP to determine the decomposition parameters. Results on the phase decomposition in selected supersaturated alloys (Cu–Co, Al–Li and Ni–Be) are reviewed to gain an insight into the benefits and difficulties of this novel analytical method.