Solidification Of Steel Ingots Research Articles

Forming of Positive Macrosegregations during Steel Ingot Solidification.

It is known that the degree of positive segregations in upper part of ingots is very sensitively dependent upon the enriched liquid velocity. In this paper, relationship between chemical composition of steel and liquid density changes are considered.Besides, the influence of the primary and secondary arm spacing (λ 1 , λ 2 ) on the liquid flow velocity, i.e. intensity of positive macrosegregations, was studied, using examples from 3-tone ingots, for different grades of steel. The elements as W, Ni, Mo, Cr, decreases the effect of density changes (dρ L /df L ), i.e. they have smaller tendency to segregation forming. Global intensity of positive macrosegregations, S g , which can be calculated by integration of local macrosegregations degree, depends approximately linearly on the liquid flow velocity.

Selection of applicability limits of a mathematical model of turbulence in formation of a steel ingot

Rational applicability limits of a turbulent model of momentum and heat transfer in a solidifying melt in an enclosure are determined based on multivariant calculations of hydrodynamic and thermophysical processes during casting and solidification of steel ingots.

A REM Tracer Study into Mechanism and Kinetics of Steel Ingot Solidification

A REM Tracer Study into Mechanism and Kinetics of Steel Ingot Solidification

Numerical model for prediction of the final segregation pattern of bearing steel ingots

Chemical heterogeneities arise during solidification of steel ingots due to long range solute transport. A model taking into account heat, mass and momentum coupled transports during solidification of multicomponent alloys in a mold, is briefly presented. A comparison between experimental and numerical results illustrates its abilities and limits in the prediction of segregation pattern in bearing steel ingots.

On the Solidification of Steel Ingots and Continuously Cast Steel Billets and Slabs

AbstractThe cast macrostructure in steel ingots and continuously cast steel billets is often divided into three zones, a chill zone at the surface, a columnar zone in the intermediate region, and large grained equiaxed zone in the centre. This paper discusses the formation of the three zones and attempts to theoretically describe their formation. The formation of the three crystal zones influences the macrosegregation in both ingots and continuously cast billets. The effect of the cast structure on macrosegregation is discussed. Centreline segregation in continuously cast billets and slabs is considered theoretically, and related to the macrosegregation in ingots. The different mechanisms leading to macro segregation in continuously cast billets; slabs, and static cast ingots are considered. Pipe formation in ingots is primarily dependent on solidification shrinkage. A simple theoretical model of pipe formation in ingots is used to delineate the most important parameters for minimizing pipe formation. The...

On the Solidification of Steel Ingots and Continuously Cast Steel Billets and Slabs

The cast macrostructure in steel ingots and continuously cast steel billets is often divided into three zones, a chill zone at the surface, a columnar zone in the intermediate region, and large grained equiaxed zone in the centre. This paper discusses the formation of the three zones and attempts to theoretically describe their formation. The formation of the three crystal zones influences the macrosegregation in both ingots and continuously cast billets. The effect of the cast structure on macrosegregation is discussed. Centreline segregation in continuously cast billets and slabs is considered theoretically, and related to the macrosegregation in ingots. The different mechanisms leading to macro segregation in continuously cast billets; slabs, and static cast ingots are considered. Pipe formation in ingots is primarily dependent on solidification shrinkage. A simple theoretical model of pipe formation in ingots is used to delineate the most important parameters for minimizing pipe formation. The same model is used to determine the extent of pipe formation at the end of solidification of a continuously cast billet. In this case it is shown that shrinkage of the solidified shell as it cools is more important than solidification shrinkage. Résumé La microstructure de lingots coulés d'acier et de billettes obtenues par coulée continue est le plus souvent divisée en trois zones: une zone refroidie rapidement près de la surface, une zone à croissance colonnaire dans la région intermédiaire et une zone de gros grains équiaxes au centre. Cet article discute de la formation de ces trois zones et décrit théoriquement leur formation. La présence de ces trois zones cristallines influence la macroségrégation dans les deux procédés. Les effets de la structure coulée sur la macroségrégation sont discutés. La ségrégation centrée dans les billettes et brames de coulée continue est considérée d'un point de vue théorique et reliée à la macroségrégation des lingots. Différents mécanismes entraînant la macroségrégation dans les deux procédés sont considérés. La formation de retassures coniques dans les lingots est principalement reliée à la contraction lors de la solidification. Un modèle théorique simple décrivant la formation de ces retassures coniques est utilisé pour cerner les paramètres les plus importants afin de minimiser cet effet. Le même modele est ensuite utilisé pour déterminer l'importance de la formation de retassures coniques à la fin de la solidification dans des billettes de coulée continue. Dans ce cas, il apparaît que la contraction de la pellicule solidifée à mesure qu'elle refroidit est plus importante que la contraction due à la solidification.

Numerical study of temperature fields in the continuous teeming of steel ingots of rectangular cross section

The thermal boundary layer approximation is used to examine the solidification of steel ingots of rectangular cross section during continuous teeming and the effect of the sides on solidification time.

Flow analysis during solidification by the direct finite difference method.

Finite difference equations are derived based on the direct finite difference method for solving fluid flow during solidification of alloys. In the analysis the darcy and laminar flows are assumed in the solid-liquid coexisting and liquid regions, respectively. Numerical examples revealed some features and effects of the fluid flow during solidification of steel ingots. These finite difference equations are applicable to solidification problems of complicated shape and boundary conditions.

Finite Element Solution of Heat Transmission in Steel Ingots

A mathematical study of the solidification of steel ingots using, for the first time, the finite element method.