Continuous Casting of High Carbon Steel: How Does Hard Cooling Influence Solidification, Micro - and Macro Segregation?

Heat transfer of the mould flux between the mould and the strand is very complicated, especially for the high carbon steel thin slab continuous casting. In this research the orthogonal experiment has been carried out, and the results showed that: the effect for the heat flux form strong to weak is: R>Na2O>F>MgO>BaO. and in the experiment range, with the R increasing, when the R, Na2O content and the F- content are increasing, the heat flux would be decreasing; with the MgO content increasing, the crystallization temperature would getting fluctuant; with the BaO content increasing, the heat flux would getting fluctuant, when its content is around 6%, the heat flux is reach its summit.

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Deformation and Structure Difference of Steel Droplets during Initial Solidification

High Temperature Materials and Processes ◽

10.1515/htmp-2016-0113 ◽

2017 ◽

Vol 36 (4) ◽

pp. 347-357 ◽

Cited By ~ 2

Author(s):

Yang Li ◽

Jing Wang ◽

Jiaquan Zhang ◽

Changgui Cheng ◽

Zhi Zeng

Keyword(s):

Carbon Steel ◽

Continuous Casting ◽

High Carbon Steel ◽

Low Carbon Steel ◽

Carbon Steels ◽

Solidification Structure ◽

Low Carbon ◽

High Carbon ◽

Peritectic Steel ◽

Initial Solidification

AbstractThe surface quality of slabs is closely related with the initial solidification at very first seconds of molten steel near meniscus in mold during continuous casting. The solidification, structure, and free deformation for given steels have been investigated in droplet experiments by aid of Laser Scanning Confocal Microscope. It is observed that the appearances of solidified shells for high carbon steels and some hyper-peritectic steels with high carbon content show lamellar, while that for other steels show spherical. Convex is formed along the chilling direction for most steels, besides some occasions that concave is formed for high carbon steel at times. The deformation degree decreases gradually in order of hypo-peritectic steel, ultra-low carbon steel, hyper-peritectic steel, low carbon steel, and high carbon steel, which is consistent with the solidification shrinkage in macroscope during continuous casting. Additionally, the microstructure of solidified shell of hypo-peritectic steel is bainite, while that of hyper-peritectic steel is martensite.

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Optimization of Submerged Entry Nozzle Depth in CC Mould / Optymalizacja Zanurzenia Wylewu W Krystalizatorze Cos

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0467 ◽

2015 ◽

Vol 60 (4) ◽

pp. 2927-2932

Author(s):

J. Pieprzyca ◽

T. Merder ◽

M. Saternus

Keyword(s):

Carbon Steel ◽

Continuous Casting ◽

High Carbon Steel ◽

Low Carbon Steel ◽

Submerged Entry Nozzle ◽

Casting Process ◽

Low Carbon ◽

High Carbon ◽

Steel Continuous Casting

The way and speed of steel flux flowing into mould of continuous casting (CC) machine belong to the important parameters characterizing the steel continuous casting process. Such flux causes determined kinds of steel circulation, which together with simultaneous steel crystallization influence the creation of ingots primary structure and quality of its surface. The article presents the results of modelling research which aim was to determine the optimal location of submerged entry nozzle in square moulds (130 x 130 mm and 160 x 160 mm) of CC machine. Such a research was carried out for two different grades of steel (low-carbon steel and high-carbon steel), which feature different parameters of casting.

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Investigation and Minimization of Slag Spot Surface Defects in Continuous Casting of High Carbon Steel Billets through Statistical Evaluation

Metals ◽

10.3390/met10070878 ◽

2020 ◽

Vol 10 (7) ◽

pp. 878

Author(s):

Yong-feng Chen ◽

Li Zhao ◽

Xiao-tan Zuo ◽

Qun-nan Tao ◽

Hong-biao Zhang ◽

...

Keyword(s):

Carbon Steel ◽

Continuous Casting ◽

Molten Steel ◽

Surface Defects ◽

High Carbon Steel ◽

Inlet Temperature ◽

External Diameter ◽

Mold Powder ◽

High Carbon ◽

Billet Surface

Slag spot surface defects often appear during continuous casting of high carbon steel billets due to the solidification characteristics of molten steel in the mold. To target the problem of surface slag spot defects that occur frequently during the continuous casting of high-carbon steel strands, we analyzed the influence of molten steel superheat, accumulated service time and the water inlet temperature of the mold, the size of the submerged entry nozzle and the physical and chemical properties of the mold powder on the slag spot defects. The production practice shows that by adjusting the superheat of molten steel to 30–35 °C, the water inlet temperature of the mold is stable at 33–35 °C. To adjust the internal and external diameter of the immersion nozzle to 30–70 mm, the viscosity and melting temperature of the mold powder were adjusted from 0.45–0.55 Pa·s, 1100–1140 °C to 0.15–0.25 Pa·s, 1020–1060 °C. The final billet surface quality was improved significantly, the billet surface was smooth, the oscillation marks were relatively smooth and regular and the slag trench ratio was reduced from the original maximum of 40–50% to less than 1%.

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