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F. Mas, Y.V. Shan, C. Tassin, E. Kozeschnik, F. Roch, P. Todeschini, Y. Brechet:
"Coupled carbon diffusion and precipitation in a dissimilar steel weld: Modelling and Characterization";
Talk: TMS 2014, San Diego USA; 02-16-2014 - 02-20-2014; in: "TMS 2014 143rd Annual Meeting & Exhibition, Annual Meeting Supplemental Proceedings", Wiley, (2014), ISBN: 978-1-118-88972-5.

Our work aims at understanding the phase transformations which occur at the interface between a low-alloy steel and a stainless steel during post-welding heat-treatment at 610°C. The large gradient of carbon chemical potential leads to cementite dissolution in the base metal, carbon diffusion across the interface and Cr-rich carbides precipitation in the weld metal.
A mesoscopic thermodynamic and kinetics model has been developed to fully couple diffusion in a multi-component system with precipitates nucleation, growth and coarsening (Numerical Kampmann-Wagner approach). This new approach has been implemented into the software MatCalc. At any distance from the interface the carbon content, the volume fraction, size distribution and composition of the precipitates are predicted and compared with experimental results : carbon profiles by WDS and SIMS, carbides characteristics by Automated Crystal Orientation Mapping in a TEM and 3D reconstruction after serial cutting with a FIB.