Influence of Continuous Casting Conditions on Segregation of Additions in EN AW 1350 Aluminum Alloy

2016 ◽  
Vol 682 ◽  
pp. 205-211
Author(s):  
Radosław Kowal ◽  
Tadeusz Knych ◽  
Andrzej Mamala ◽  
Paweł Kwaśniewski ◽  
Wojciech Ściężor ◽  
...  

Integrated continuous casting processes are an important element of the production process in modern industry. Requirements for quality and exploitation properties of products obtained using continuous casting processes necessitate a revision of the role of impurities distribution in the material. This paper concerns on the influence of the casting process on the distribution of alloy additions. Spectroscopy studies were performed for the most sensitive elements, from the segregation, (i.e. : iron and silicon) point of view. Next obtained research results were correlated with the parameters of chemical composition such as casting speed, the presence of a modifier and the processing of metal crystallization zone. Analysis of the results clearly shows the presence of iron and silicon normal macrosegregation. It was observed that the concentration of these elements is highest in the casting axis and, in the case of iron, is 50% higher in the axis than in the circumference of casts.

2012 ◽  
Vol 535-537 ◽  
pp. 633-638 ◽  
Author(s):  
Zheng Hai Zhu ◽  
Sheng Tao Qiu

It was analyzed by strain-induced precipitation model that Nb(C,N) precipitation in micro alloy steel slab was effected by strain rate during continuous casting process. The results are as follows: The changing of casting speed could effect the time for 5%precipitation of Nb(C,N), which was decreasing with increasing casting speed at certain temperature and strain rate. Slab strain and strain rate were too small in bending zone and leveling zone. The effect of slab strain rate on Nb(C,N) precipitation could be ignore when Nb(C,N) precipitation in continuous casting process was studied.


Metals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 993
Author(s):  
Yingying Zhai ◽  
Kefeng Pan ◽  
Dapeng Wu

While the solidification macrostructure of continuous cast billets is an important factor influencing the final performance and rolling yield of oil casing steel, the continuous casting process parameters have a direct influence on the solidification structure. This study simulated the solidification process of the continuous casting round billets of oil casing steel using a cellular automaton–finite element (CAFE) model. According to the simulation results, at a superheat degree of 20–35 K, a casting speed of 1.9–2.1 m/min, and a secondary cooling specific water flow of 0.34–0.45 L/Kg, the solidification structure had a relatively high equiaxed crystal ratio and small average grain radius. Guided by the simulation results, this paper establishes optimal process schemes for producing 26CrMoVTiB steel round billets, comparatively analyzes the equiaxed crystal ratio and central shrinkage of round billets produced according to these schemes, and defines the optimal continuous casting process conditions, which are: superheat degree = 25 K, casting speed = 2.1 m/min, and specific water flow = 0.35 L/Kg. When adopting these process parameters, the 26CrMoVTiB steel round billets demonstrate a tiny central shrinkage and an equiaxed crystal ratio of 45.2%.


2009 ◽  
Vol 79-82 ◽  
pp. 1269-1272
Author(s):  
Wei Chen ◽  
Bao Xiang Wang ◽  
Yu Zhu Zhang ◽  
Jin Hong Ma ◽  
Su Juan Yuan

In this paper, a three-dimensional finite element model is developed to simulate and analyze the turbulent flow in the mould of billet continuous casting. The result shows that if the SEN is used in the continuous casting process, there exists a symmetrical stronger vortex in the middle of the mould and a weaker vortex above the nozzle. The casting speed, the depth and diameter of SEN all have significant effect on the fluid flow field and the turbulent kinetic energy on the meniscus, and then have effect on the billet quality. At the given conditions, the optimum set of parameters is: the casting speed 0.035 , the depth of the SEN 0.1 , the diameter of the SEN 0.025 . Online verifying of this model has been developed, which can be proved that it is very useful to control the steel quality and improve the productivity.


2007 ◽  
Vol 561-565 ◽  
pp. 3-4 ◽  
Author(s):  
Joon Yang Chung

Continuous casting is the essential process converting liquid steel to solid in the form of slabs or billets/blooms in the steel plant. The economy and quality of the steel products are greatly dependent on how successfully the continuous casting is performed. New technologies have been actively developed in the process during the last decades in order to increase the productivity and, therefore, to decrease the operational cost. Since its first commissioning of a slab caster in 1976, POSCO has constructed a number of continuous slab, bloom and billet casters including a thin slab caster not only for plain carbon steels but for stainless steels. Through the operation of various types of continuous casters for more than 30 years so far, POSCO has steadily developed fundamental technologies and operational know-how and achieved the equipment innovations to improve the surface and internal qualities of cast products as well as to extend the productivity of continuous casters. Furthermore, POSCO has deepened the basic understanding on the solidification phenomena of liquid steel and also accumulated the engineering backgrounds to design the most optimal continuous casters. It has also devised the indispensable and auxiliary equipments and the key technologies to control the process precisely and efficiently in order to guarantee the quality and productivity. An innovative technology under development is the POCAST process, where controlled amount of the pre-molten mold flux instead of conventional powder mold flux is continuously fed into free surface of molten steel through the plunger-type feeding system from the flux melting furnace. In order to prevent the molten flux from freezing at the meniscus, a reflective insulation cover is installed, leading to the suppression of thermal radiation from the molten steel and flux. It is generally understood that, as casting speed increases, the occurrence of breakout increases since mold lubrication becomes insufficient due to the lack of mold flux flow from the meniscus into the solid shell/mold boundary. However, by utilizing the especially composition controlled pre-molten flux, it becomes possible to eliminate the formation of slag bear in the mold. Therefore, the mold flux consumption rate is increased even at the reduced oscillation rate & stroke and more importantly, the mold flux infiltration becomes more uniform throughout the boundary between the mold and the solidified shell. This consequently results in drastic reduction of the formation and depth of the oscillation mark and the occurrence of surface hooks without increasing the possibility of breakout, as has been proved in the casting trials carried out with the 10 ton pilot slab caster in Pohang. A key trend in the development of the continuous casting process is to reduce the thickness of cast products. Examples include thin slab casting and strip casting. In the thin slab casting process, a major drawback is the relatively low casting speed and, as a result, the inefficient equipment layout in the plant where two casters are connected to a hot rolling unit. The drawback could be resolved if the casting speed exceeds a certain limit. At the high casting speed, the productivity of casting becomes equivalent to that of hot rolling, and the thin slab casting plant is to be designed so that one strand


2008 ◽  
Vol 58 (12) ◽  
pp. 650-655 ◽  
Author(s):  
Hidetoshi Takagi ◽  
Yasuhiro Uetani ◽  
Masayoshi Dohi ◽  
Toru Watanabe ◽  
Tomokazu Yamashita ◽  
...  

2015 ◽  
Vol 817 ◽  
pp. 3-7
Author(s):  
Xing Han ◽  
Bo Shao ◽  
Hai Tao Zhang ◽  
Ke Qin ◽  
Jian Zhong Cui

With the cladding casting equipment, which was self-designed and self-made, 4045/3003 composite ingot, which is in size of Φ140mm/Φ110mm, has been manufactured by direct cooling continuous casting by adjusting and optimizing the technological parameters. The process was investigated involving macro-morphology and microstructure near the interface between the two different aluminum alloys at different positions, and distributions of both components and hardness of the cladding ingot. In addition, the tensile strengths were tested. The results showed that metallurgical bonding of two different aluminum alloys could be obtained by direct-chill semi-continuous casting process. The diffusion layer, which is about 15μm on average, has formed on the two sides of composite interface during casting process. From the side of 4045 aluminum alloy to the side of 3003 aluminum alloy, the Si content has a trend to decrease, as well as the hardness, while the Mn content has a trend to increase gradually. Tensile strength of the coated ingot reaches 117.3MPa, which is higher than the core-material matrix (3003 aluminum alloy), indicating the bonding of the two alloys belongs to metallurgical bonding.


2021 ◽  
Vol 75 (1) ◽  
pp. 31-37
Author(s):  
Aleksandra Pataric ◽  
Marija Mihailovic ◽  
Branislav Markovic ◽  
Miroslav Sokic ◽  
Andreja Radovanovic ◽  
...  

Microstructure assessment is crucial for the design and production of high-quality alloys such as cast aluminum alloy ingots. Along with the effect of a more homogeneous microstructure to result in much better mechanical properties, better as-cast alloy quality indicates a higher efficiency of the aluminum alloys production process. During the aluminum alloy solidification process many microstructural defects can occur, which deteriorate the mechanical properties and hence decrease the usability of such an ingot. Application of the electromagnetic field during the vertical continuous casting process significantly reduces occurrence of these defects. In the present study, EN AW 7075 alloy samples were cast with and without application of an electromagnetic field and examined regarding the microstructure, electrical conductivity, and changes in the phase composition. The obtained results clearly show that it is possible to decrease or avoid casting defects by the electromagnetic field application as verified by the microstructure characterization and quantification, electrical conductivity tests and differential thermal analysis (DTA).


2021 ◽  
Vol 118 (6) ◽  
pp. 611
Author(s):  
Shujun Li ◽  
Xueyan Du

The effect of casting speed on slag-inclusion defects in 1050 × 200 mm ultra-low-carbon automobile steel (UAS) slabs was studied by performing nail plate experiments and by monitoring the liquid level fluctuations during the continuous casting process. The number, location, length, and proportion of slag-inclusion defects in hot-rolled coils produced at different casting speeds were analyzed. The results showed that the defects in the hot-rolled coils were mainly owing to the mold protective slag. For the continuous casting speed of 1.6 m/min, the fraction of slag-inclusion defects was the lowest (at 5.3%), and the number of slag-inclusion defects was lower than for the other casting speeds. The length of slag inclusions was under 900 mm. Furthermore, the number of slag-inclusion defects on the upper and lower surfaces was smaller than those for the other casting speeds. At different casting speeds, slag-inclusion defects mainly existed within 100 mm of the edge on both surfaces of hot-rolled coil plates. The fluctuation within the 0–1 mm range was 98.1% for the casting speed of 1.6 m/min, indicating that the flow rate of molten steel on both sides of the nozzle was relatively stable, which helps to control slag-inclusion defects in hot-rolled coils.


2010 ◽  
Vol 26 (8) ◽  
pp. 1015-1016 ◽  
Author(s):  
H. Soda ◽  
A. McLean ◽  
G. Motoyasu

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