Dr Ing rer nat Paul OlaruSETEC- SCO Expert

CH-6006 Luzern, Switzerland

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Detection of Inclusions and Development of Structural Metal Analyzer (SMA) in Steel Alloys &

l’Analyse Inclusionnaire en élaboration des alliages métalliques

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Summary: 1. Abstract2. Technological activities today 3. Diagrams for study inclusions-14. Diagrams for study inclusions-25. STATE of The ART – Casting defects6. Ch.A. THE INDUSTRIAL PRACTICS to DETECT STEEL INCLUSIONS7. Ch.B. TECHNOLOGICALY PROCESSES FOR measure the STEEL

Cleanliness in C.CASTING 8. Ch.C. Structural Metal Analyzer (SMA)- new technology for assuring

steel quality 9. Ch.D1.Interferometallography –InterMet 10.Ch.E1. VXMODEL AND GO!SCAN 3D11. Ch.RESEARCH DEBUT 12. CONCLUSIONS 1&2 13. Finally Discussions

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Abstract:One scientifical and technological multiphase flow model is proposed to

predict the behaviour in the Pouring Furnaces (fig.1) and in the Ladle production(fig.2), regarding entrained inclusions in liquid steel, as they enter the orifice of aSMA (Structural Metal Analyzer) sensor for assuring steel quality (fig.3).The SMA method of measurement is based on the UCnF & Vyborcntmat-SMP(VycnT) pseudo-composite technique.Analysis of the liquid metal flow field- used the VycnT – it solving by the three related mechanisms:the Seebeck, Peltier and Thomson mechanisms and effects taking into account the presence of aself-induced electromagnetic field.When an entrained non-conducting inclusion passes through the orifice ofthe probe, in the presence of a direct current, the change in the electricalresistance of the VycnT , due to its presence in the VycnT can register aresistive pulse. Such signals, in turn, can be used to detect the numbers andsizes of entrained inclusions.The trajectories of these entrained inclusions have been modeled using a momentum equation bysolving COMSOL Multiphysics models. External forces acting on the particles include those forstandard drag (Stokes), added mass, fluid acceleration, buoyancy and, most significantly,electromagnetic.The boundary effects on Stokes drag are also taken into account.Predicted voltage pulse signals are compared with experimental values derived from some basedexperiments, UCnF & Vyborcntmat-SMP (VycnT) pseudo-composite technique.

Keywords: inclusions, multiphase flow, liquid steel, particle motion, trajectory, electromagnetic force

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Figure 1: Process Control for Pouring furnaces-SinterCast

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2. Technological activities todayFig.1,2,3;

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Figure 2: Process control for ladle production-SinterCast

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Figure 3. The Sinter Cast process flow begins by obtaining the thermal analysis sample after the magnesium and inoculant base treatment reaction has been completed. Depending on the result of the thermal analysis, the wire feeder is automatically instructed to add the necessary amount of additional magnesium and inoculants, in cored wire form. So, the ladle is available to begin casting

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Figure 4. After the base treatment, the iron is in its most stable state and corrective additions of magnesium and/or inoculants can be made to change the solidification behavior of each ladle to the desired coordinates before the start of casting. A two-step measure-and-correct control strategy provides the opportunity to compensate for the variation that naturally occurs in the foundry process and to eliminate the risks associated with porosity defects appearing in the final product.

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Inclusion, in the short words is defined as the material with different composition (cinders, flux fondants, loam, products resulting from the chemical interaction which take place at the elaboration and pouring of the liquid metal) of the basic material, isolated in the continuous weight of the metallic material.The cast parts come from the elaboration and pouring technology, while the parts obtained through plastic deformation come from the ingot or the used semi-product .The non-metallic inclusion has a strip form which produces local discontinuities in the part. These could be plastic (sulphides, silicates) and at the microscope they appear oblong, compact or fragile (oxides), which at the microscope are divided into small pieces. In all cases, the inclusion reduces considerably the plasticity and the mechanic characteristics of the metallic material.Ex. the calcium aluminates are dangerous, especially at contact during rolling. My experience in China&Russia ( Ch&Ru) steel metallurgy shows :

1.The effect of an inclusion over the properties of fatigue is dependent of the following: the control strategy (fig.4),the size of the inclusion, shape, heat and elastic properties and the affiliation at a matrix. 2.These factors are related to a form factor and to the tension distribution around the inclusion. 3.The size of an inclusion has a major effect over the resistance of fatigue .

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3. Diagrams for study inclusions-1 (by experience)

Figure 5. CaO and Al203 can form a number of solid andliquid inclusions at steelmaking temperatures around 1600°C (1 878°K).

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4. Diagrams for study inclusions-2( by experience)

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5. STATE of The ARTI. Casting Defects :Defects may occur due to one or moreof the following reasons:•Fault in design of casting pattern•Fault in design on mold and core•Fault in design of gating system and riser•Improper choice of molding sand•Improper metal composition inadequatemelting temperature and rate of pouring

II. Classification of the Principal Groups of Casting Defects (figure 13)Surface Defects (sd):sd1.Blow, sd2.Scar, sd3.Blister, sd4.Drop, sd5.Scab, sd6.Penetration, sd7.BuckleInternal Defects (id):id1,Blow holes, id2.Porosity, id3.Pin holes, id4.Inclusions, id5.DrossVisible Defects (vd):vd1.Wash, vd2.Rat tail, vd3.Swell, vd4.Mis run, vd5.Cold shut, vd6.Hot tear, vd7.Shrinkage, vd8. Mould shift, vd9. Cold shift ;

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Fig.13. The Principal Groups of Casting Defects

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6. Ch.A. THE INDUSTRIAL PRACTICS to DETECT STEEL INCLUSIONSMeasurement techniques range from direct methods, which are accurate butcostly, to indirect methods, which are fast and inexpensive, but are only reliable as relative indicators. The amount, size distribution, shape and composition of inclusions should be measured at all stages in steel production.I.Methods-Experience Direct Applications – SIDEX GL.I.1. Inclusion Evaluation of Solid Steel Sections- MOST USED1) Metallographic Microscope Observation (MMO) :Examples are as shown in Fig.14 and 15. This method is can only reveal

the 2-dimensional section of an inclusion, however, inclusions are 3 dimensional in nature.

Fig. 14 Agglomeration of round silica inclusions Fig.15 Typical exogenous inclusions in deep-drawing steel : a- Vitreous inclusion (either alumina silicate or calcium-alumina silicate) ; b- Opaque inclusion (either alumina silicate or a mixed oxide phase which is very probably of exogenous origin) ; c- Crystals of alumina on the surface of a globular slag inclusion

a b c

Silica (SiO2) inclusions are generally spherical owing to being in a liquid or glassy state in the molten steel. Silica can also agglomerate into clusters as shown in figure 14. Silica inclusions in Si-killed steel are generated by the reaction between the dissolved oxygen and the added aluminum and silicon deoxidants are typical deoxidation inclusions. Alumina (Al2O3) inclusions in EAF steel, inclusions are dendritic when formed in a high oxygen environment.During cooling, the concentration of dissolved oxygen/nitrogen/sulfur in the liquid becomes larger while the solubility of thoseelements decreases. Thus inclusions such as alumina, silica, AlN, and sulphide precipitate. Sulphides (SOx ) form interdendritically during solidification, and often nucleate on oxides already present in the liquid steel. These inclusions are normally small (<10μm).

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2) Image Analysis (IA) : This enhancement to MMO improves on eye evaluation by using highspeed computer evaluation of video-scanned microscope images to distinguish dark and light regions based on a gray-scale cutoff.3) Sulfur Print This popular and inexpensive macrographic method distinguishes macroinclusions and cracks by etching sulfur-rich areas. It is subject to the same problems as other 2-D methods.4) Scanning Electron Microscopy (SEM) : This method clearly reveals the three-dimensional morphology and the composition of each inclusion (Fig.16,17, 18, 19 and 20). Composition can also be measured with Electron Probe Micro Analyzer (EPMA). Extensive sample preparation is required, however, to find and expose the inclusion(s).

Fig. 16 Dendritic and clustered alumina inclusions (left), and coral-like alumina inclusions (right) formed during deoxidation of pure iron . Alumina inclusions are dendritic when formed in a highoxygen environment

Fig. 17: a) Alumina cluster during deoxidation of low carbon steel by aluminum . Alumina inclusions formed during the deoxidation of EAF steel ; b: flower-like plate alumina; c: aggregation of small polyhedral particles)

Fig. 18. SEMs and TEMs of AlN inclusions in high Al ingot ((a)+(a’) plate-like, (b)+ (b’) feathery, (c)+(c’)branched rod-like).

Fig.19. Exogenous inclusions act as heterogeneous nucleus sites for precipitation of new inclusions during their motion in molten steel (Fig.19a); Exogenous inclusions move, due to their large size, they may entrap deoxidation inclusions such as Al2O3on their surface (Fig.19b );

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Fig.20 Erosion of refractories, including well block sand, loose dirt, broken refractory brickwork and ceramic lining particles, is a very common source of large exogenous inclusions which are typically solid and related to the materials of the ladle and tundish themselves. They are generally large and irregular-shaped

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5) Optical Emission Spectrometry with Pulse Discrimination Analysis (OES-PDA) : The OES method analyzes elements dissolved in liquid steel. Inclusions cause high-intensity spark peaks (relative to the background signal from the dissolved elements), which are counted to give the PDA index.6) Laser Microprobe Mass Spectrometry (LAMMS) : Individual particles are irradiated by a pulsed laser beam, and the lowest laser intensity above a threshold value of ionization is selected for its characteristic spectrum patterns due to their chemicalstates. Peaks in LAMMS spectra are associated with elements, based on comparison with reference sample results.7) X-ray Photoelectron Spectroscopy (XPS) : This method use x-rays to map the chemical state of individual inclusions larger than 10μm.8) Auger Electron Spectroscopy (AES) : This method use electron beams to map the composition of small areas near the surface of flat samples.9). Cathodoluminescence Microscope : Under microscope, the steel or lining sample section is stimulated by a cathode-ray (energetic electron-beam), to induce cathodoluminescence (CL). The color of CL depends on the metal ions type, electric field, and stress, allowing inclusions to be detected. Examples are given in Fig.21 and 22.

Fig. 21 Inclusion clusters on a bubble surface

Fig.22 A slag spot defect on a cold-rolled sheet

10.Inclusion Agglomeration and CloggingThe agglomeration of solid inclusions can occur on any surface aided by surface tension effects, including on refractory and bubble surfaces as shown in figure 21 . The high contact angle of alumina in liquid steel (133°C-147°C ) encourages an inclusion to attach itself to refractory in order to minimize contact with steel. High temperatures of 1550°C enable sintering of alumina to occur.

11.Slag spots on cold rolled sheetTwo types of exogenous slag spots have been observed. The first contained calcium, magnesium, aluminum and oxygen and the second contained calcium, sodium, magnesium, aluminum and oxygen. Slag spots are chemically similar to the inclusions found from the flange crack studies. An example of slag spot on a cold rolled sheet is given in figure 22 .

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I.2.Inclusion Evaluation of Solid Steel Volumes- MOST USED in my SIDEX experienceSeveral methods directly measure inclusions in the three-dimensional steel matrix. 1) Conventional Ultrasonic Scanning (CUS) :The transducer (typically a piezoelectric) emits a sound pressure wave that is transferred into the sample with the aid of a coupling gel. The sound waves propagate through the sample, reflect off the back wall and return to the transducer. The magnitude of the initial input pulse and the reflected signals are compared on an oscilloscope to indicate the internal quality of the sample. Obstructing objects in the path of the sound will scatter the wave energy. This nondestructive method detects and counts inclusions larger than 20μm in solidified steel samples.2) Mannesmann Inclusion Detection by Analysis Surfboards (MIDAS): Steel samples are first rolled to remove porosity and then ultrasonically scanned to detect both solid inclusions and compound solid inclusions / gas pores. This method was recently renamed as the Liquid Sampling Hot Rolling (LSHP) method.3) Scanning Acoustic Microscope (SAM) : In this method, a cone-shaped volume of continuous cast product is scanned with a spiraling detector, such as a solid ultrasonic system, which automatically detects inclusions at every location in the area of the sample surface, including from surface to centerline of the product.4) X-ray Detection : Inclusions images are detected by their causing variation in the attenuation of x-rays transmitted through the solid steel. An inclusion distribution can be constructed by dividing a sample into several wafers and subjecting each to conventional x-rays to print penetrameter radiograghs for image analysis.5) Chemical Dissolution (CD): Acid is used to dissolve the steel and partially extract inclusions. The inclusion morphology and composition can be detected by another method like SEM, or be fully extracted by dissolving all the steel sample. The disadvantage is that the acid will dissolve away FeO, MnO, CaO, MgO in the inclusions. Thus this method is good to detect Al2O3 and SiO2 inclusions. 6) Slime (Electrolysis): This method is also called Potentiostatic Dissolution Techniques. A relatively large (0,2Kg to 2,2kg) steel sample is dissolved by applying electric current through the steel sample immersed in a FeCl2 or FeSO4 solution. This method was used to reveal the individual, intact inclusions in (fig. 16-22) . The main disadvantage of this method is the cluster inclusions possibly break into separate particles after extraction from steel. 7) Electron Beam melting (EB): A sample of Al-killed steel is melted by an electron beam under vacuum. Inclusions float to the upper surface and form a raft on top of the molten sample. The usual EB index is the specific area of the inclusion raft. An enhanced method (EB-EV – Extreme Value) has been developed to estimate the inclusion size distribution. 8) Cold Crucible (CC) melting: Inclusions are first concentrated at the surface of the melted sample as in EB melting. After cooling, the sample surface is then dissolved, and the inclusions are filtered out of the solute. This method improves on EB melting by melting a larger sample and being able to detect SiO2.

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9) Fractional Thermal Decomposition (FTD): When temperature of a steel sample exceeds its melting point, inclusions can be revealed on the surface of the melt and decomposed. Inclusions of different oxides are selectively reduced at different temperatures, such as alumina-based oxides at 1400°C or 1600°C, or refractory inclusions at 1900°C. The total oxygen content is the sum of the oxygen contents measured at each heating step. 10) Magnetic Particle Inspection (MPI): This method also called magnetic leakage field inspection can locate inclusions larger than 30μm in sheet steel products. The test procedure consists of generating a homogeneous field within the steel sheet that is parallel to the sheet surface. If an inhomogeneity (such as an inclusion or a pore) is present, the difference in magnetic susceptibility will force the magnetic flux field to bend and extend beyond the surface of the sheet. The major disadvantage is poor resolution of inclusions that are close together.

1.3 Inclusion Size Distribution After Inclusion Extraction1) Coulter Counter Analysis : This method, by which particles flowing into this sensor through its tiny hole are detected because they change the electric conductivity across a gap, measures the size distribution of inclusions extracted by Slime and suspended in water.2) Photo Scattering Method1: Photo-scattering signals of inclusions (that have been extracted from a steel sample using another method such as slime) are analyzed to evaluate the size distribution.3) Laser-Diffraction Particle Size Analyzer (LDPSA): This laser technique can evaluate the size distribution of inclusions that have been extracted from a steel sample using another method such as Slime.

1.4. Inclusion Evaluation of LiquidThere are several approaches can be used to detect the inclusion amount and size distribution in the molten melts.1) Liquid System Tech : This method captures the reflections from ultrasound pulses to detect on-line inclusions in metal-liquid2) Liquid Metal Cleanliness Analyzer (LIMCA): This on-line sensor uses the principle of the Coulter Counter to detect inclusions directly in the liquid metal. Commonly this method is used for aluminum and other metals, and it is still under development for steel.3) Confocal Scanning Laser Microscope: This new in-situ method can observe the behavior of individual inclusions moving on the surface of the molten steel, including their nucleation, collision, agglomeration, and pushing by interfaces ( fig.23).

Figure 23. Alumina inclusion clustering process on a melt surface by confocalscanning laser microscope observation

4). Electromagnetic Visualization (EV) : This Lorentz-force-based detection system is used to accelerate inclusions to the top free surface of the melted sample of metals and highly conductive opaque fluids.

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2. Indirect Detection MethodsOwing to the cost, time requirements, and sampling difficulties of direct inclusion measurements, steel cleanliness is generally measured in the steel industry using total oxygen, nitrogen pick-up, and other indirect methods.2.1. Total Oxygen Measurement The total oxygen (T.O.) in the steel is the sum of the free oxygen (dissolved oxygen) and the oxygen combined as non-metallic inclusions. Free oxygen, or “active” oxygen can be measured relatively easily using oxygen sensors. It is controlled mainly by equilibrium thermodynamics with deoxidation elements, such as aluminum. Because the free oxygen does not vary much (3-5ppm at 1600°C for Al-killed steel ), the total oxygen is a reasonable indirect measure of the total amount of oxide inclusions in the steel. Due to the small population of large inclusions in thesteel sample.Thus, T.O. content really represents the level of small oxide inclusions only. The T.O. measured from liquid samples roughly correlates with the incidence of slivers in the product. In particular, tundish samples are commonly taken to indicate cleanliness for slab dispositioning.For example, Ch&Ru requires the T.O. in tundish samples <29-30ppm to warrant shipment of cold-rolled sheet without special inspection. The following general conclusions can be derived in short words. 1) T.O. in Ch&Ru steel has steadily decreased with passing years, as new technology is implemented. For example, T.O. at Ch&Ru dropped from 40-50 ppm in 1970’s , to 20 ppm in 2009’s;2) Plants with RH degassing achieve lower T.O. (10-30ppm) than plants with ladle gas-stirring (35- 45 ppm).3) T.O. generally drops after every processing step: 40ppm (ladle), 25ppm (tundish), 20ppm (mold), and 15ppm (slab).

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2.2. Nitrogen PickupThe difference in nitrogen content between steelmaking vessels is an indicator of the air entrained during transfer operations. Nitrogen pickup thus serves as a crude indirect measure of total oxygen, steel cleanliness, and quality problems from reoxidation inclusions. Thus, to reduce nitrogen pickup, deoxidation is best carried out after tapping. Ch&Ru plant measurements confirm this, as nitrogen pickup reduced from 10-20ppm for deoxidation during tapping to 5ppm after tapping. Summarize minimum nitrogen pick-up and nitrogen contents measured in Ch&Ru steel at every processing step for several steel plants. Measurements in the tundish and mold were excluded because they tend to be high due to sampling. Practice reveals the following conclusions:1. Nitrogen in Ch&Ru steel slabs is about 30-40ppm at most steel plants. It is controlled mainly by the steelmaking converter or electric furnace operation, but is affected by refining and shrouding operations.2. Nitrogen pick-up is deceasing with passing years, owing to new technology and improved operations. For example, at Ch&Ru s works, nitrogen pick-up from tundish to mold decreased from 9ppm in 1988, to 1ppm in 2012.3. Generally, nitrogen pick-up can be controlled at 1-3 ppm from ladle to mold. With optimal transfer operations to lessen air entrainment, this pickup can be lowered during steady state casting to less than 1ppm. Nitrogen pick-up is discussed further in the Transfer Operations section of this paper.2.3 Concentration MeasurementFor Ch&Ru steels, the dissolved aluminum loss also indicates that reoxidation has occurred.However, this indicator is a less accurate measure than nitrogen pickup because Al can also be reoxidized by slag. The silicon pickup, manganese pickup can be also used to evaluate the reoxidation process.2.4 Lining Refractory ObservationAnalysis of the lining refractory composition evolution before and after operations can be used to estimate inclusion absorption to the lining and the lining erosion. Also, the origin of a complex oxide inclusion can be traced to lining refractory erosion by matching the mineral and element fractions in the slag with the inclusion composition. 2.5 Slag Composition MeasurementFirstly, analysis of the slag composition evolution before and after operations can be interpreted to estimate inclusion absorption to the slag. Secondly, the origin of a complex oxide inclusion can be traced to slag entrainment by matching the mineral and element fractions in the slag with the inclusion composition. These methods are not easy, however, due to sampling difficulties and because changes in the thermodynamic equilibrium must be taken into account.2.6 Tracer Studies for Determining Exogenous Inclusions from Slag and Lining Erosion : Tracer oxides can be added into slags and linings in ladle, tundish, mold, or ingot trumpet, and top compound. Typical inclusions in the steel are then analyzed by SEM and other methods. If the tracer oxides are found in these inclusions, then the source of these inclusions can be decided.

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2.7 Submerged Entry Nozzle (SEN)- CloggingShort SEN life due to clogging is sometimes an indicator of poor steel cleanliness. The composition of a typical clog during Ch&Ru steel continuous casting is: 51.7% Al2O3, 44% Fe, 2.3% MnO, 1.4% SiO2, 0.6% CaO, which shows that nozzle clogs are often caused by a simultaneous buildup of small alumina inclusions and frozen steel. Thus, SEN clogging frequency is another crude method to evaluate steel cleanliness. The cause and prevention of SEN clogging was reviewed by Kemeny and Thomas .

3. Final Product TestsThe ultimate measure of cleanliness is to use:1. Destructive mechanical tests to measure formability, 2. Deep-drawing, and / or bending properties of the final sheet product, or fatigue life of

test specimens or product samples. 3. Other sheet tests include the Hydrogen Induced Crack test and Magnetoscopy.4. Another example is the inclusion inspection method in ultra-sonic fatigue test. These tests are needed to reveal facts such as the potential benefit of very small inclusions (< 1μm), which should not count against cleanliness. So, because exogenous inclusions can originate from a combination of several sources, methods for their prevention are not likely to be simple. It is only through the correct combination of all these sources and removal mechanisms that the incidence of large non-metallic inclusions in steels can be reduced. For detecting Exogenous Inclusions in steel, the following methods are suitable:1. Ultrasonic Scanning, 2. Microscope Obs., 3. Sulfur Print, 4. Slime (Electrolysis), 5. X-ray, 6. SEM, 7. Slag Composition Analysis, and Refractory Observation8. SPECIAL Interferometallography –InterMet .

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7. Ch.B. TECHNOLOGICALY PROCESSES FOR measure the STEEL Cleanliness in C.CASTING My experience,(for example), regarding the study of inclusion removal found that ladle treatment lowered inclusions by 65~75%; the tundish removed 20~25%, although reoxidation sometimes occurred; and the mold removed 5~10% of the inclusions.Tundish operations greatly affect steel cleanliness, as covered in reviews by McLean and Schade.The following important factors are discussed here ( I have separate technologically work):1. tundish depth and capacity, 2. casting transitions, 3. tundish lining refractory, 4. tundish flux, 5. gas stirring, 6. tundish flow control. VERY IMPORTANT- Clogging and New Techniques at SEN (Submerged Entry Nozzle); Examples of the SEN clogging fig. 24,25,26.The nozzle is a one of the few control parameters that is relatively inexpensive to change, yet has a profound influence on the flow pattern and thus on quality. Nozzle parameters include bore size, port angle and opening size, nozzle wall thickness, port shape (round vs square vs oval), number of ports (bifurcated vs multiport), and nozzle bottom design (well vs. flat vs. sloped), and submergence depth .Both too large and too small submergence depth increases problems with longitudinal cracks and transverse depressions.

Fig. 24 Example of clogging at SEN of continuous casting

Fig.25 Example of SEN nozzle clogging (longitudinal and transverse

Fig. 26 Inclusions clogged at SEN during the continuous carting of Ch&Ru steels: (left &middle: sphere-like cluster ; right: dendritic cluster and plate-like clusters.

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In The EU Metallurgy common methods in use :1.The ASCAT uses "intelligent" software to emulate specialized knowledge that can be used to evaluate causes of clogging/erosion, slag treatment practices, castability, degasser circulation optimization, and slab disposition. One ASCAT system is now in use at the U.S. Steel Munhall Research and Technology Center. 2. The high-end analyzer G8 GALILEO -for the automatic and precise determination of oxygen, nitrogen and hydrogen in solid materials.3. The G4 PHOENIX DH hot extraction analyzer is the right solution for accurate and rapid diffusible hydrogen measure to avoid embrittlement, hydrogen-induced cracking and other costly failures.4. The Aztec Steel is an automated package developed specifically for the analysis and classification of steel inclusions, using Energy Dispersive X-ray microanalysis (EDS) in a scanning electron microscope (SEM). 5.The FOUNDRY-MASTER Xpert -evaluated using total O2 measurements by Optical Emission Spectroscopy (OES) with Pulse Discrimination Analysis (PDA), especially auto SEM inclusion analyses.

The Exogenous inclusions in steelExperience shows : Exogenous inclusions arise primarily from the incidental chemical (re-oxidation) and mechanical interaction of liquid steel with its surroundings (slag entrainment and erosion of lining refractory).In machining, they produce chatter, causing pits and gouges on the surface of machined sections, frequent breakage, as well as excessive tool wear. Exogenous inclusions act as heterogeneous nucleus sites for precipitation of new inclusions during their motion in molten steel.

Fig. 27. Size distribution of large inclusions in a continuous casting slab-Slime extraction

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C1. Unidirectional Carbon nFiber (UCnF) Reinforced Shape memory polymers-(SMPs) nanostrip multilayers-Vyborcntmat-SMP ( VycnT) : the nanostrip dimensions: 5 x 25 x 125 nm (fig.28); Presentation of the Vyborcntmat-SMP ( VycnT) ,after 25 tests , max. strain 100%;

Figure 29. Effect of the glass transition

Figure 28. Presentation of the Vyborcntmat-SMP ( VycnT)

8.Ch.C. Structural Metal Analyzer (SMA)- new technology for assuring steel quality

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Figure 30. Electrical vs. Temperature for the Shape Memory Polymers-(SMPs) nanostrip multilayers- Vyborcntmat-SMP ( VycnT)

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C2. Vyborcntmat-SMP(VycnT) nanostrip multilayers-Pseudo-Composite (0°;45°;90°;45°;0°)

Overall conductivity of composite: 0.0344 S/m with ~10x10 contacts at each interface; This kind of UCnF&Vyborcntmat-SMP( VycnT) Pseudo-Composite must be used steel industrially:

Figure 31. Vyborcntmat-SMP( VycnT) nanostrip contruct multilayers- Pseudo-Composite

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C3. Modeling the Non-Percolation State Carbon fibers contribute very little to the resistanceBoth Unidirectional Carbon nFiber (UCnF) and polymer are very conductive thermic & electric ( fig.32)

therefore σCF = ∞

• Unidirectional Carbon nFiber (UCnF)tested good conductor thermo-electric;• The carbon fiber was consideredconductive, and the polymer wasconsidered virtually non-conductive(Fig.33)

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Figure 34. MP & Unidirectional Carbon nFiber (UCnF)- Vyborcntmat-SMP( VycnT) nanostrip spot front size , 34a-low zoom ; 34b-front spot-size;

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b)

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C4.Unidirectional Carbon nFiber (UCnF)-TESTS, (figure 35)

1. The effect of unidirectional carbon nfiber content and verification

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C5. Unidirectional Carbon nFiber (UCnF) Reinforced Shape memory polymers-(SMPs) nanostrip multilayers-Vyborcntmat-SMP ( VycnT) - The VycnT & SMA actions in use and verifications-TESTS, (fig. 36,37,38)

Simultaneously passing an electrical current through the orifice so as to create a small electric sensing zone in the vicinity of the orifice.Continuously monitoring the electrical resistance during the steel sampling period, in order to detect the passage of entrained non-metallic inclusions passing through the SMA into the silica/quartz tube.Determining the size of each inclusion detected, based on the peak height, current, and electrical resistivity of steel.Drawing a sample of liquid steel into an insulating silica tube through a small orifice

VycnT & SMA – USED in The VycnTSTREAM( VTS) method in work

Fig. 37.The System VycnT & SMA is capable now of collecting process data from the melting, molding, pouring and shakeout operations. These data are compiled into a single database, together with the VycnT &SMA process control results, to provide improved process control and production traceability.

Fig. 36 The VycnT & SMA in use

Fig.38

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Fig.39Fig.40

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Example : The VycnTSTREAM( VTS)- optical measurements method in work (fig.43)

The mechanism for collecting samples and optical camera inside of a robust housing

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Fig.44 Fig.45

Figure 46

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9.Ch.D1.Interferometallography –InterMet - To discover, study and understand the Surface Defects structure, microstructure and nanostructure for the Exogenous Inclusions in steelsusing new material pseudo-composite VybormemT-SMP.Interferometallography –InterMet :Combines an interferometer and metallographic science into one technologic apparatus-instrument. RESULTS (see figures 47, 48 );It is used to discover, study and understand the structure, microstructure and nanostructure for the materials, engineering surfaces that demand testing rapid analysis and evaluation with high resolving power.

Al2O3 & trace-scratches Aligned oxide-islands alumina oxide-bandstrace-scratches

Figure 47. Figure 48

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49 5051

5253

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Ch.10.E1. VXMODEL AND GO!SCAN 3D

Since you do not necessarily wantto print your 3D scan files rightaway and may rather wish to bringthem to CAD first, VXmodelprovides simple yet effectivebridge-to-CAD functionalities.Within a few minutes, you canextract entities and surfaces fromthe file generated with theGo! SCAN 3D, and import themdirectly into your CAD software touse as a reference for creating anaccurate 3D model of the part thatyou can send to your 3D printerwhenever you are ready.

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Fig.55. Technological FLOW Chart

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Ch.11. RESEARCH DEBUT 1Graphene, the final steel-filter: gridmesh-sieve (Gmhs) technologieA sheet of graphene is an ultrathin lattice of carbon atoms that is one atom thick, so pores in graphene are defined at the atomic scale. Realize the minuscule holes in graphene—a hexagonal array of carbon atoms, like atomic-scale chicken wire—occurs in a two-stage process.First, the graphene is bombarded with gallium ions, which disrupt the carbon bonds. Second, the graphene is etched with an oxidizing solution that reacts strongly with the disrupted bonds—producing a hole at each spot where the gallium ions struck.

By controlling how long the graphene sheet is left in the oxidizing solution, the researchers can control the average size of the pores /inclusions/impurities.Ind.PRACTICE shows: Each pore/inclusion/impurity starts developing its own behavior. We then developed a model to interpret the measurements, and used it to translate the experiment's measurements into estimates of pore size. Based on the model, they found that the diameter of many of the pores was below 1 nanometer, which—given the single-atom thickness of graphene—makes them among the smallest pores through which scientists have studied ion flow.With the model, the team calculated the effect of various factors on pore behavior, and found that the observed pore behavior was captured by three main characteristics: a pore's size, its electrical charge, and the position of that charge along a pore's length.

Knowing this, researchers may one day be able to tailor pores at the nanoscale to create ion-specific gridmesh-sieve / membranes for applications such as environmental sensing and trace pseudo-metal in the steel fabrication.So, "It's kind of a new frontier in gridmesh-sieve (Gmhs) technologies, and in understanding transport through these really small pores in ultrathin materials.

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Ch.11. RESEARCH DEBUT 2 - Structural Metal Analyzer-Dynamically Scan (SMA-DS)

SMA-DS: Dynamically scans the sample by utilizing the electron microscope, not the EDX system for control. It is the only all-in-one reporting software that provides completely automated reporting capabilities in a fully integrated SEM/EDX The combination of speed and automated reporting provides the complete solution to the steel industry with a faster return on investment.

Fig.59-SMA-DS :Automated SEM/EDS Provides Fast and Accurate Analysis-The latest advances in scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) technology that enables fast and accurate analysis of as many as 8- 9,000 inclusions per hour with Aspex Explorer. It is possible to solve inclusion problems in steelmaking and metals applications.

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CONCLUSIONS (some) from my personal activities 25 years in Siderurgy:1. How to determine which technology detection of inclusions in Steel Alloys& l’Analyse Inclusionnaire en élaboration des alliages métalliques is best suited for real/typical applications ?.2. Why: a. Advantages and limitations of X-Ray Fluorescence (XRF),b. Advantages and limitations of Laser Induced Breakdown Spectroscopy (LIBS),c. Advantages and limitations of Optical Emissions Spectroscopy (OES);3. Why one detection technology may be more applicable for our/your application and how to make this distinction between these technologies ?.4.The methodology to study non-metallic inclusions in steel has changed due to newsteelmaking technologies and due to the development of (new) research equipment. In the20th century the major revolution in steelmaking has been the development and industrialapplication of continuous casting.5.Continuous casting requires the steel to be completely deoxidised, which is achieved by adding strong deoxidisers, in particular aluminium. 6. The deoxidation practice results in large amounts of non-metallic inclusions that are largely removed into the ladle slag. But, yet a fraction of the inclusions stays in the steel melt and can have a detrimental effect on the productivity and on steel quality, due to nozzle clogging and (surface) defect formation.

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7. Detailed laboratory studies show spherical, plate-like and faceted inclusions as well. It has been found that the shapes of inclusions depend on dissolved oxygen and aluminium activities, stirring conditions and holding time. Oxygen contents in steels studied in the end ‘70’s to ‘20’s could be fairly high.8. Although inclusion removal in the ladle and in the tundish can be modelled reasonably well, the mechanism of deoxidation is poorly understood and the various aluminium oxide shapes have not been properly explained?!. 9.The lack of understanding of the mechanisms of formation and evolution of non-metallic inclusions in the liquid steel is probably the cause that no attempts to control the aluminium oxide shapes have been described.10.Hypothese from the lab. experiments : By controlling how long the graphene sheet is left in the oxidizing solution, the researchers can control the average size of the pores/inclusions/impurities!?.

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Finally Discussions: Detection of Inclusions and Development of Structural Metal Analyzer(SMA) regardingSteel Alloys & l’Analyse Inclusionnaire en élaboration des alliages métalliques How to Choose & Criteria :1.Portable XRF, LIBS or OES for Testing and Inspection, 2.The ASCAT system,3.The G8 GALILEO high-end analyzer system ,4.The G4 PHOENIX DH system,5. The AZtecSteel automated system,6. The FOUNDRY-MASTER Xpert system

Propose New/Challenging methods vs. daily detection inclusions and defects: C.Structural Metal Analyzer (SMA) & Vyborcntmat-SMP ( VycnT) ,D. Interferometallography –InterMet ,E. GO!SCAN 3D (VXMODEL ):

Portable analyzers are extremely useful for analyzing and identifying alloys defects when reliable materials verification is needed. These tools are well suited to a variety of industries and purposes, such as quality control, inspection testing, and materials authentication in the production. Different techniques are available to accomplish these tasks and each technology has its advantages and limitations.

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CLARIFICATIONS :

Steel cleanliness is an important topic that has received much attention in the literature.I RECOMMEMD to study : I. The extensive review on clean steel by Kiessling in 1980 summarized inclusion and trace elements

control and evaluation methods, especially for ingots. II. More recent reviews of this topic have been made by Mu and Holappa (1992) 21) and by Cramb (1999) which added extensive thermodynamic considerations. III. McPherson and McLean (1992) reviewed non-metallic inclusions in continuously casting steel, focusing on the inclusion types (oxides, sulfides, oxysulfides, nitrides and carbonitrides), inclusion distributions and methods to detect inclusions in this process. IV. Zhang and Thomas (2003) reviewed detection methods of inclusions, and operating practices to improve steel cleanliness at the ladle, tundish and continuous caster.

V. Blockfehlerkatalog/Catalogue of Ingot Defects /Cataloque de defauts sur lingots /Ed.vom Stahlinstitut VDEh, ISBN 978-3-514-00791-8; 2016

VI. Atlas of Precipitates in Steels,Ed.by Working Group Electron,Microscopy of Materials,Committee Steel Institute VDEh ISBN 978-3-514-00681-2 ; 2016

The actual scientific & technologic work is an extensive review and analysis, by experience, on the inclusions in the steel continuous casting, their sources, morphology, formation mechanisms, detection methods-most used, and the effect of various continuous casting operations.

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“If you can’t study and understand InterMet, you can’t perform SMA”