Preprint Article Version 1 This version not peer reviewed

Crucial Mechanism to the Eutectoid Transformation of Wüstite Scale on Low Carbon Steel

Version 1 : Received: 29 January 2017 / Approved: 29 January 2017 / Online: 29 January 2017 (10:47:49 CET)

How to cite: Lin, S.; Huang, C.; Wu, M.; Wang, W.; Hsieh, K. Crucial Mechanism to the Eutectoid Transformation of Wüstite Scale on Low Carbon Steel. Preprints 2017, 2017010130 (doi: 10.20944/preprints201701.0130.v1). Lin, S.; Huang, C.; Wu, M.; Wang, W.; Hsieh, K. Crucial Mechanism to the Eutectoid Transformation of Wüstite Scale on Low Carbon Steel. Preprints 2017, 2017010130 (doi: 10.20944/preprints201701.0130.v1).

Abstract

It is important to realize the transformation behavior of wüstite because it greatly affects the final structure of the oxide layer and the surface quality of the steel products. In the present study, the transformation behaviors of the wüstite layer are examined under nearly-oxygen-free conditions, to simulate the cooling processes after the hot rolled strip is coiled. As the single phase wüstite was prepared at 950˚C, the 460˚C transformed oxide layer was composed of a mixture of iron and magnetite formed through eutectoid reactions. For the 750˚C-fabricated wüstite, only magnetite was observed after transformation, without iron precipitates and residual wüstite. It is speculated that the unusual transformation behavior of the low-temperature-made wüstite results from the pseudo-structural intermediate phase transformation between wüstite and magnetite. This pseudo-structure is a pre-transformed wüstite and of various concentration of ferrous ion, which is determined by the fabrication conditions. During the hot strip mill process, the so-called wet scale, wüstite, is produced continuously from finish mill to laminar flow sections and ended at 570˚C. Consequently, the final eutectoid transformation below 570˚C is dominantly controlled by the surface temperature ranged from 750˚C to 950˚C for low carbon steel.

Subject Areas

wüstite; magnetite; eutectoid transformation; oxide scale; hot strip mill

Readers' Comments and Ratings (0)

Leave a public comment
Send a private comment to the author(s)
Rate this article
Views 0
Downloads 0
Comments 0
Metrics 0
Leave a public comment

×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.