Three-Dimensional Atom Probe Analysis of Carbon Distribution in Low-Temperature Bainite
نویسندگان
چکیده
A bainitic microstructure with fine ferrite plates (20 to 40 nm) in a matrix of high-carbon retained austenite, obtained by isothermal transformation at 200°C, was characterized with an energy-compensated optical position-sensitive three-dimensional atom probe. The average carbon concentration in the austenite was found to be 8.0±1.6 at.% and in the bainitic ferrite 1.1±0.7 at.%. The latter concentration is much higher than expected from paraequilibrium between austenite and ferrite, and the austenite carbon concentration is found to be slightly higher than the T0 limit.
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