Thermodynamic Analysis of Liquid Steel Refining by Complex La–Ce–Al-Based Alloy

Simulation of Oxygen and Nitrogen Removal from Steel by Means of Titanium and Aluminum Authors' computer program was employed in the simulation of the course of steel refining by means of simultaneously used aluminium and titanium. The mass and chemical composition of liquid steel and non-metallic precipitates, were calculated at constant or variable temperature. The influence of assumed nitrides form on the results of simulation was determined. Nitrides may be considered either as separate phases or as the components of non-metallic solution. The stoichiometry of titanium oxide obtained also influences the results of simulation. Parallel analysis of steel refining was carried out with the use of FactSage program. As a result of calculations the subsequent states of equilibrium between steel and non-metallic phase were determined. It was found that aluminium and titanium nitrides may exist only as the components of oxide-nitride solution, not as separate phases.

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Thermodyanmics of CaO in Slag Reduced by Carbon during VD Process of Hollow Steel 95CrMo and its Effect on Inclusions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.788.289 ◽

2014 ◽

Vol 788 ◽

pp. 289-297 ◽

Cited By ~ 1

Author(s):

Chuan Jie Cai ◽

Shao Bo Zheng ◽

Jing Chen ◽

Zhi Yang Ye ◽

Hui Gai Li ◽

...

Keyword(s):

Calcium Aluminate ◽

Liquid Steel ◽

Treatment Process ◽

Regular Solution Model ◽

Slag Basicity ◽

Smelting Process ◽

Steel Temperature ◽

Vacuum Degree ◽

Thermodynamic Conditions ◽

Steel Refining

With the help of thermodynamics calculation and kinetic model, the generation mechanism of calcium aluminate inclusions in hollow steel 95CrMo was analyzed. The steel was produced in a certain steelmaking factory whose smelting process is EAF-LF-VD-CC and the micreostructure of the hollow steel 95CrMo samples have been investigated by SEM and EDS. Based on Lumsden’s regular solution model to molten slags, the possibility of CaO in slags reduced by carbon during hollow steel refining in VD furnace was calculated. The influence of furnace vacuum, slag basicity and liquid steel temperature on the reduction of CaO in slag by carbon was discussed. It was showed that the carbon dissolving in liquid steel might reduce CaO in slags to dissolved calcium which could also react with Al2O3 and turn into dot calcium-aluminate inclusions in the steel. The calcium-aluminate existing in the hollow steel easily turned into dot inclusions, which would decrease the fatigue life of the hollow steel. According to the thermodynamic conditions of dot calcium-aluminate inclusions, the influence of slag basicity, temperature of liquid steel, vacuum degree and the Ca treatment process on the quantity of dot inclusions in hollow steel 95CrMo was analyzed.

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The Influence of Slenderness Ratios of Multi-Hole Ceramic Filters from SF - 1.67 to SF - 8.36 of Filter Surface on Efficiency of Liquid Steel Refining from Non-Metallic Phase

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.212.205 ◽

2013 ◽

Vol 212 ◽

pp. 205-208 ◽

Cited By ~ 1

Author(s):

Krystian Janiszewski ◽

Bożena Gajdzik ◽

Andrzej Wyciślik

Keyword(s):

Liquid Steel ◽

Slenderness Ratio ◽

Filter Material ◽

Metallic Phase ◽

Ceramic Filter ◽

Process Efficiency ◽

Ceramic Filters ◽

Filter Surface ◽

Theoretical Assumptions ◽

Steel Refining

We propose in this publication the introduction of new, additional definition describing the multiple orifice ceramic filters used in research works on the liquid steel filtrations, calling this the filter slenderness ratio. In order to confirm the theoretical assumptions we have performed a series of the laboratory scale experiments (for the filter slenderness ratio SF - 1.67 to SF - 8.36). The influence of the filter slenderness on the filtration process efficiency has been determined through variations in quantities and surface shares of the non-metallic phase in the filtrated steel in relation to the non-filtered steel. We present also the results of researches on the separating surfaces between the liquid steel and the ceramic filter material, which in form of photos and scanning microscope microanalyses are put together in the publication.

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Liquid Steel Refining in the Ladle with Non-Oxidising Synthetic Slag

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.60.2_192 ◽

1974 ◽

Vol 60 (2) ◽

pp. 192-205 ◽

Cited By ~ 1

Author(s):

Kazuo OKOHIRA ◽

Norio SATO ◽

Hisashi MORI

Keyword(s):

Liquid Steel ◽

Synthetic Slag ◽

Steel Refining

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Influence of Slenderness Ratios of a Multi-Hole Ceramic Filters at the Effectiveness of Process of Filtration of Non-Metallic Inclusions from Liquid Steel

Archives of Metallurgy and Materials ◽

10.2478/v10172-012-0002-y ◽

2012 ◽

Vol 57 (1) ◽

pp. 135-143 ◽

Cited By ~ 1

Author(s):

K. Janiszewski

Keyword(s):

Liquid Steel ◽

Slenderness Ratio ◽

Ambient Air ◽

Negative Influence ◽

Argon Atmosphere ◽

Ceramic Filter ◽

Ceramic Filters ◽

Air Atmosphere ◽

Metallic Inclusions ◽

Steel Refining

Influence of Slenderness Ratios of a Multi-Hole Ceramic Filters at the Effectiveness of Process of Filtration of Non-Metallic Inclusions from Liquid SteelThe paper presents the results of investigations of the process of filtration of solid non-metallic inclusions from liquid steel with use of multi-hole ceramic filters (filtrating surfaces) characterised by a varying slenderness ratios. In order to eliminate the negative influence of the ambient air atmosphere the investigations have been carried out under a protective argon atmosphere. The experimental results obtained have proved earlier suggestions of papers [9-12] about the negative influence of ambient air atmosphere, as well as the essential influence of slenderness ratio of the used multi-hole ceramic filter at the increase of effectiveness of the liquid steel refining processes carried out through steel filtration.

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