RECENT ATOM-PROBE STUDIES AT IMR - A COMPREHENSIVE REVIEW

This paper reviews our recent atom probe research activities conducted at Institute for Materials Research (IMR), Tohoku University, during a period of 1990 to date. The atom probe research started at IMR when the authors constructed an energy compensated time-of-flight atom prob e in 1990. Since then, this instrument has been employed for various m etallurgical problems, providing better understandings to mechanisms o f microstructural evolution in various metallic materials. Notable ach ievements are studies of precipitation processes in aluminum alloys, n anocrystallization processes of amorphous alloys, microstructural char acterizations of magnetic thin films and various other metallic materi als. A new instrument equipped with a reflectron type time-of-flight a tom probe and a position sensitive atom probe (PoSAP) was constructed in 1994. This instrument allowed three dimensional visualizations of a tom distributions in alloys with an atomic resolution. PoSAP has been employed to characterize microstructures in Cr-Fe and Co-Cr(-Ta) magne tic alloys.