Fast Granularization of Lath-Like Bainite in FeNiC Alloys During Isothermal Holding at Ms+20 K (+20 degrees C)

Meriem Ben Haj Slama (1, 2, 3) , Nathalie Gey (3, 2) , Lionel Germain (2, 3) , Jean Christophe Hell (4) , Kangying Zhu (4) , Sébastien Allain (1, 2, 5)

1 IJL - Institut Jean Lamour
2 Labex DAMAS
3 LEM3 - Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux
4 ArcelorMittal Maizières Research SA
5 ENSMN - Ecole Nationale Supérieure des Mines de Nancy

A fast << granularization >> of lath-like bainite is observed in an Fe5Ni0.13C (wt pct) alloy during isothermal holding at Ms+ 20 K (+20 A degrees C). The microstructure evolution with holding time is characterized by Scanning Electron Microscopy and Electron BackScatter Diffraction. Granularization starts once the bainitic transformation is finished and degrades the mechanical properties. The granularization involves a rapid decrease in 60 deg < 111 > misoriented bainite laths to a dislocated granular bainite, followed by a slower dislocation rearrangement to sub-grain boundaries and more random boundaries. During the granularization, the carbides go through a ripening process.

Mots clés: Cementite; Bainite; Misorientation angle; Isothermal holding; Bainitic ferrite

Domaines: Matériaux

Meriem Ben Haj Slama, Nathalie Gey, Lionel Germain, Jean Christophe Hell, Kangying Zhu, et al.. Fast Granularization of Lath-Like Bainite in FeNiC Alloys During Isothermal Holding at Ms+20 K (+20 degrees C). Metallurgical and Materials Transactions A, 2016, 47 (1), pp.15-18. ⟨10.1007/s11661-015-3209-5⟩. ⟨hal-01292800⟩