Crystallography and Mechanical Properties of Ultrafine TRIP-Aided Multi-Phase Steels


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This study aims at examining thermomechanical controlled process to realize ultrafine TRIP-aided multi-phase microstructures in low carbon steels. Heavy deformation at a supercooled austenite region was found to lead the formation of 2 μm ferrite as well as retained austenite with high volume fraction. The morphology of retained austenite was changed from film-like shape to granular shape with lowering finish rolling temperature in austenite field. This ultrafine TRIP-aided multi-phase steel showed good balance of tensile strength with total elongation, ie. 1080MPa and 26.9%. A novel in-situ neutron diffraction measurement demonstrated that the retained granular austenite transformed to martensite at a relatively large strain compared with the retained film austenite. The therein-underlying mechanism of the good mechanical properties was discussed from the view points of the morphological and thermodynamical stabilization of retained austenite.



Materials Science Forum (Volumes 539-543)

Main Theme:

Edited by:

T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran




M. Wakita et al., "Crystallography and Mechanical Properties of Ultrafine TRIP-Aided Multi-Phase Steels", Materials Science Forum, Vols. 539-543, pp. 4351-4356, 2007

Online since:

March 2007




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