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S. Dépinoy, C. Toffolon-Masclet, A. Gourgues-Lorenzon, E. Kozeschnik, B. Marini, F. Roch:
"Experimental study and thermokinetic modelling of carbides precipitation sequences in 2,25Cr-1Mo bainitic steel";
Talk: THERMEC´2016, Graz (invited); 2016-05-29 - 2016-06-03.

In this work, carbides precipitation sequences have been studied for different conditions of time and temperature ranging respectively between 0 and 24 hours and 650 to 725°C. The carbides have been thoroughly characterized by means of TEM sudy on carbon replicas and electro-etching extraction procedure coupled with X-ray diffraction allowing a complete description of these phases: crystallographic structure, size, morphology and chemical composition. Nucleation sites and nucleation mechanisms have also been determined: M3C precipitate upon decomposition of austenite, then M7C3 carbides nucleate at the interface between cementite and matrix. M2C precipitate homogenously in the matrix, while M23C6 are located at dislocations within the bainitic laths. These observations were successfully reproduced by a thermokinetic approach using the Matcalc software