Modification of oxide inclusions in calcium-treated Al-killed high sulphur steels

Modification of oxide inclusions in calcium-treated Al-killed high sulphur steels

Gollapalli, Veerababu (Visakhapatnam Steel Plant)
Rao, M.B.Venkata (Visakhapatnam Steel Plant)
Karamched, P.S. (University of Oxford)
Borra, C.R. (TU Delft (OLD) MSE-1)
Roy, G.G. (Materials Engineering Indian Institute of Technology)
Srirangam, Prakash (University of Warwick)

2018

A study has been carried out to understand the modification of alumina inclusions in Al-killed high sulphur steel with calcium treatment. For calcium treatment to be effective, a general practice is to desulphurise the steel to prevent the formation of solid CaS inclusions that are harmful to steel quality and final properties. To avoid this additional desulphurising step, the authors developed a new approach of calcium treatment of steel at an industrial scale. This approach involves treating the liquid steel with calcium treatment at low aluminium levels which enables formation of liquid calcium aluminate inclusions (C12A7) in the melt and then adding remaining amount of required aluminium. Based on this principle, Al-S diagram has been developed and calcium treatment has been modified accordingly. The inclusion transformation and morphology were studied using scanning electron microscope /energy dispersive spectroscopy analysis and. activity of CaS was calculated.

aluminium-killed steel
billet
calcium aluminates
high sulphur
Inclusion
oxy-sulphides

http://resolver.tudelft.nl/uuid:5a42f9b3-6a54-4b05-9d6d-32c39e8ffa22

https://doi.org/10.1080/03019233.2018.1443382

2019-03-15

0301-9233

Ironmaking & Steelmaking: processes, products and applications, 46 (2019) (7), 663-670

Accepted Author Manuscript

Institutional Repository

journal article

© 2018 Veerababu Gollapalli, M.B.Venkata Rao, P.S. Karamched, C.R. Borra, G.G. Roy, Prakash Srirangam