Formation of Nonmetallic Inclusions during Ladle Treatment of Pipe Steels

2021 ◽  
Vol 2021 (7) ◽  
pp. 864-873
Author(s):  
A. Yu. Em ◽  
O. A. Komolova ◽  
A. M. Pogodin ◽  
K. V. Grigorovich
Keyword(s):  
Nonmetallic Inclusions ◽  
Ladle Treatment ◽  
Pipe Steels

Application of microcrystalline complex modifiers for steel ladle treatment. Part 1. The role of nonmetallic inclusions in steel quality forming

2021 ◽  
Vol 77 (3) ◽  
pp. 295-309
Author(s):  
V. A. Golubtsov ◽  
I. V. Ryabchikov ◽  
I. V. Bakin ◽  
A. Ya. Dynin ◽  
O. N. Romanov ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Nonmetallic Inclusions ◽  
Steel Production ◽  
Good Alternative ◽  
Ladle Treatment ◽  
Steel Ladle ◽  
Long Time ◽  
Negative Effect ◽  
Favorable Conditions ◽  
Inclusions In Steel

Contamination of steel by nonmetallic inclusions (NI) has a negative effect on mechanical characteristics of metal used under no favorable conditions. Conditions of NI forming in the process of steel smelting, ladle treatment and casting considered. It was shown that it is impossible to get rid of many NI. However, the task of forming less “harmful” NI having minimal effect on the decrease of finished products indices is quite practicable. To refine steel of NI it is reasonable to accomplish operations in a melt to modify NI morphology from dangerous acute-angled aluminous to globular oxide-sulphide. This task can be solved by introduction into metal complex modifiers comprising calcium, barium, strontium and rare earth metals. Addition of complex modifiers is a good alternative to complicative and long-time operations to decrease NI general content to lower levels, for example, by long-time metal ladle treatment. Application of the method enables in some situation to avoid expensive operations related to deep metal desulphuri zation and its dehydronization. Clean steel production becomes considerably easier at application of multicomponent alloys, obtained by a technology of accelerated crystallization. Application of such compositions results in forming globular oxide and oxide-sulphide compounds, as well as eutectics with low-melting point, which are comparatively quickly removed out of liquid metal. At that due to decreasing of liquation processes forming in the liquid metal, higher quality of large ingots and work-pieces, obtained from 420 t mass ingots can be reached.

scholarly journals CONTENT MODIFICATION OF DIFFERENT TYPES OF NONMETALLIC INCLUSIONS DURING LOW-CARBON IF STEEL LADLE TREATMENT

2019 ◽  
Vol 62 (5) ◽  
pp. 345-352 ◽  
Author(s):  
D. V. Gorkusha ◽  
K. V. Grigorovich ◽  
A. V. Karasev ◽  
O. A. Komolova
Keyword(s):  
Nonmetallic Inclusions ◽  
Ladle Treatment ◽  
Gas Analysis ◽  
Metallographic Analysis ◽  
Steel Ladle ◽  
Interstitial Free ◽  
If Steel ◽  
Low Carbon ◽  
Metallic Inclusions ◽  
Fractional Gas Analysis

Development of advanced materials for the automotive industry allows us to produce a lighter body without losing strength characteristics of the structure. It became possible by the creation and subsequent introduction into the production of such steel grades as IF (Interstitial Free) – steel with no interstitial solute atoms to strain the solid iron lattice and IF-BH (Bake Hardening) – steel with hardening during hot drying. The article provides a brief overview of the history of the emergence of IF steel and the current situation in the production of it in Russia. One of the quality criteria for steels of IF grades is purity of the metal by non-metallic inclusions (NMI), which negatively affect the plastic properties of the material, lead to the formation of surface defects of flat rolled products and reduce the manufacturability due to a decrease in the casting speed of steel, as they cause overgrowing of steel casting nozzles. The article presents investigation results of the content, composition, size and morphology of non-metallic inclusions (NMI) in the metal samples taken at all stages of ladle treatment and casting of IF steel grade production using quantitative metallographic analysis, electrochemical dissolution (ED) followed by X-ray microanalysis of isolated inclusions, Auger electron spectroscopy and fractional gas analysis (FGA). As a result of the analysis of inclusions in the studied samples using a scanning electron microscope, according to morphological features, five characteristic types of inclusions were identified, which reduce the performance properties and strength cha racteristics of the materials produced from them. Results of the analysis of nonmetallic inclusions in metal samples obtained by the ED method are in good agreement with the results of the determination of oxide nonmetallic inclusions by the FGA method. The method of fractional gas analysis shows the dynamics of changes in the content of various types of oxide nonmetallic inclusions during the secondary (ladle) treatment of steel. It is shown that application of the FGA method allows to make analysis of causes of the harmful NMI formation in the metal and to correct operations at ladle treatment.

Study of effect of wheel steel microalloying by calcium and barium on nonmetallic inclusions modification

2020 ◽  
Vol 76 (6) ◽  
pp. 564-572
Author(s):  
A. V. Gaivoronoskii ◽  
N. V. Pavlova
Keyword(s):  
Service Life ◽  
High Speed ◽  
Nonmetallic Inclusions ◽  
Ladle Treatment ◽  
Wheel Steel ◽  
Rolling Stock ◽  
Steel Ladle ◽  
Treatment Technology ◽  
Cored Wire ◽  
Globular Form

The increase in freight cars axis loads, dynamic loads and heat impact on the wheels, change of other factors, stipulated by railway transport traffic intensification lead to considerable decrease of service life of solid-rolled wheels. To increase the service life of them, provision of the transport metal purity in non-deformed oxide nonmetallic inclusions with high content of Al2O3, decrease of general steel pollution by nonmetallic inclusions by micro-alloying and modification is an actual task. The purpose of the study was elaboration of wheel steel ladle treatment technology, including the steel micro-alloying and modification by barium-containing alloys to create material, which could meet high operation requirements, made to the railway wheels of new generation, intended to operate under increased axis loads conditions at the modern high-speed rolling-stock. It was shown, that replacement of everywhere applied silicocalcium by barium-based alloys is one of perspective ways of modification mechanism perfection. Results of industrial tests of micro-alloying of wheel steel by barium during ladle treatment presented. It was shown, that application for modification of cored wire with silicobarium filler instead of cored wire with silicocalsium filler СК-30, enabled to transform the nonmetallic inclusions into globular form practically completely, to raise the steel purity for all kinds of inclusions in both middle and maximum points range and to refine to some extent the grain size by 1-2 points. In the pilot metal at the depth of 40 mm from the surface, the gain was somewhat finer and more uniform (number 7), comparing with the existing technology (number 5-6). The pollution of the pilot metal by nonmetallic inclusions meets requirements of GOST 10791—2011 for category A and those of the standard EN 13262: 2004+А2:2011 for category 1.

Regarding the mechanism of formation of nonmetallic inclusions conglomerates of system Al2O3-MgO

2019 ◽  
Vol 75 (12) ◽  
pp. 1341-1351
Author(s):  
A. A. Safronov ◽  
V. S. Dub ◽  
V. V. Orlov ◽  
K. L. Kosyrev ◽  
A. S. Loskutov ◽  
...  
Keyword(s):  
Nonmetallic Inclusions ◽  
Mechanism Of Formation

Calculation model of formation of nonmetallic inclusions of multilayer morphology in weld metal

2018 ◽  
Vol 2018 (2) ◽  
pp. 5-10
Author(s):  
L.A. Taraborkin ◽  
◽  
V.V. Golovko ◽  
Keyword(s):  
Weld Metal ◽  
Nonmetallic Inclusions ◽  
Calculation Model

HP MAGNET PLATE STEEL

Alloy Digest ◽  
2004 ◽  
Vol 53 (11) ◽  
Keyword(s):  
Physical Properties ◽  
Tensile Properties ◽  
Magnetic Permeability ◽  
Nonmetallic Inclusions ◽  
Heat Treating ◽  
Plate Steel ◽  
High Saturation ◽  
Careful Control ◽  
Residual Elements ◽  
High Magnetic Permeability

Abstract HP magnet steel is designed for use wherever high magnetic permeability or high saturation values are required. Its magnetic qualities result from careful control of sulfur and residual elements plus the special deoxidization practice, which minimizes nonmetallic inclusions. This datasheet provides information on composition, physical properties, and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: CS-144. Producer or source: ISG Plate International Steel Group Inc.

ARMCO FORMABLE 70 HR

Alloy Digest ◽  
1979 ◽  
Vol 28 (5) ◽  
Keyword(s):  
Nonmetallic Inclusions ◽  
High Strength ◽  
Heat Treating ◽  
Rolled Steel ◽  
Low Carbon ◽  
Controlled Processing ◽  
High Strength Level ◽  
Hot Rolled ◽  
Hot Rolled Steel ◽  
Special Composition

Abstract ARMCO FORMABLE 70 HR is a hot-rolled steel with excellent ductility, weldability and edge-tear resistance at a minimum yield strength of 70,000 psi (483 MPa). For this relatively high strength level, it has unusually good fabricating properties that are the result of closely controlled processing of a fully killed, low-carbon, vacuum-degassed, columbium-alloyed steel. This special composition and processing practice minimize harmful nonmetallic inclusions that hamper formability. Typical applications include automotive reinforcements, truck parts and construction components. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-359. Producer or source: Armco Inc., Eastern Steel Division.

scholarly journals Evolution of the Numerical Model Describing the Distribution of Non-Metallic Inclusions in the Tundish

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2229
Author(s):  
Tomasz Merder ◽  
Jacek Pieprzyca ◽  
Marek Warzecha ◽  
Piotr Warzecha ◽  
Artur Hutny
Keyword(s):  
Numerical Model ◽  
Liquid Steel ◽  
Nonmetallic Inclusions ◽  
Steel Production ◽  
Cfd Modeling ◽  
Water Model ◽  
Working Space ◽  
Production Stages ◽  
Steel Flow ◽  
Flow Controllers

Continuous casting is one of the steel production stages, during which the improvement in the metallurgical purity of steel can be additionally affected by removing nonmetallic inclusions (NMIs). This can be achieved by means of various types of flow controllers, installed in the working space of the tundish. The change in the steel flow structure, caused by those flow controllers, should lead to an intensification of NMIs removal from the liquid metal to the slag. Therefore, it is crucial to understand the behavior of nonmetallic inclusions during the flow of liquid steel through the tundish, and particularly during their distribution. The presented paper reports the results of the modeling studies of NMI distribution in liquid steel, flowing through the tundish. CFD modeling methods—using different models and computation variants—were employed in the study. The obtained CFD results were compared with the results of laboratory tests (using a tundish water model). The results of the performed investigations allow us to compare both methods of modeling; the investigated phenomena were microparticle distribution and mass microparticle concentration in the model fluid. The validation of the CFD results verified the analyzed computation variants. The aim of the research was to determine which numerical model is the best for describing the studied phenomenon. This will be used as the first phase of a larger research program which will provide for a comprehensive study of the distribution of NMIs flowing through tundish steel.

Sign in / Sign up

Export Citation Format

Share Document