Effects of Replacing Fluorine with Sodium and Titanium Oxides on Continuous Casting of Steel Mold Powders Lubrication

محورهای موضوعی : Ceramics

Ahmadreza Arefpour ¹ , Ahmad Monshi ² , Ali Saidi ³

1 - Department of material engineering, Najaf Abad Branch, Islamic Azad university, Isfahan, Iran
2 - Department of materials Engineering, Najaf Abad branch, Islamic Azad University, Isfahan
3 - Department of materials Engineering, Najaf Abad branch, Islamic Azad University, Isfahan

تاریخ دریافت : 1393/02/29 تاریخ پذیرش : 1393/10/02 تاریخ انتشار : 1393/12/10

کلید واژه: Viscosity, Continuous Casting, Mold Powder, Fluorine,

چکیده مقاله :

Mold powders are used as raw materials in continuous casting of steel industry; Also they are mostly composed of aluminum, calcium, silica oxides, alkaline and earth-alkaline oxides along with carbon and fluor. Two of the most important duties of mold powders are the lubrication of the space between mold walls and steel shell, and heat transfer control between steel shell and the copper mold. Fluor is one of the most important constituents of mold powders and is employed to control viscosity in order to obtain favorable lubrication and solidification temperature control in order to control heat transfer. The fluor in the mold powder is added to it with the aid of some fluorided compounds like fluorine (CaF2). This study has used Fluorine to make a powder similar to the reference sample, with the use of portland cement clinker and fluorine. Moreover, groove viscometer studies have been conducted here to compare sample viscosities to the viscosity of the reference sample. In addition XRD as well as SEM analyses were conducted. As a result, crystalline phase of cuspidine was found in the glass matrix indicating that the chemical compound in sample 1 may be a suitable substitute, as compared to the reference sample, for the mold powder used in continuous casting steel industry.

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