A direct evidence of solute interactions with a moving ferrite/austenite interface in a model Fe-C-Mn alloy

Fréderic Danoix (1) , Xavier Sauvage (1) , Didier Huin (2) , Lionel Germain (3) , Mohamed Gouné (4)

1 GPM - Groupe de physique des matériaux
2 ArcelorMittal
3 LEM3 - Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux
4 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

The coupled-solute drag during ferrite growth in steels is widely discussed in the literature and remains still controversial since little direct evidences were adduced to support this effect. In this paper, from a correlative microscopy approach, a selected migrating ferrite/austenite interface in a model FeMnC alloy is quantitatively analysed by atom probe tomography and Energy Dispersive X-Ray Spectroscopy at the nanoscale. They show unambiguously a strong co-segregation of both carbon and manganese at the interface during ferrite growth at 680 °C. The obtained results support the coupled-solute drag effect as an operating mechanism during ferrite growth.

Mots clés: Atom probe tomography (APT); Energy Dispersive X-ray Spectroscopy (EDX); Interface migration; Interface segregation; Austenite to ferrite transformation; Steel

Domaines: Matériaux

Fréderic Danoix, Xavier Sauvage, Didier Huin, Lionel Germain, Mohamed Gouné. A direct evidence of solute interactions with a moving ferrite/austenite interface in a model Fe-C-Mn alloy. Scripta Materialia, 2016, 121, pp.61-65. ⟨10.1016/j.scriptamat.2016.04.038⟩. ⟨hal-01324531⟩