1. |
Model study for subsurface trajectory of 75FeSi and SiMn ferroalloys in steel |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 379-386
Young Eun Lee,
Halvard Tveit,
Roderick Ian Lawrence Guthrie,
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摘要:
The present study, using a low temperature model, is aimed at examining the feasibility of subsurface melting of 75FeSi and SiMn alloys added to steel baths. Wooden objects, simulating 75FeSi and SiMn of various sizes and shapes, were prepared so as to have same density ratio of 75FeSi and SiMn to steel, and their subsurface trajectories in water or zinc chloride solution following three meters of free fall through air were analyzed using video images. In general, subsurface retention times were observed to gradually increase with size of object up to a steady value. For those objects simulating 75FeSi, it was found to be dependent on shapes, spherical objects having longer retention times. The effect of shape was less pronounced for objects simulating SiMn. In a gas stirred bath, smaller cuboids for SiMn were entrained. Comparisons with estimated melting times of 75FeSi suggest that regular sized 75FeSi (ex. 20 to 50 mm) will float up and melt at the surface, when dropped to the steel bath in a ladle. A similar situation is expected with SiMn alloys. Subsurface melting may be feasible by reducing the size of 75FeSi addition from 1 to 5 mm dia. and of SiMn down to about 10 mm while simultaneously applying sufficient turbulent mixing of steel bath or providing entraining downflow velocities in the range of 10 to 30 cm/s.
ISSN:0003-8962
DOI:10.1002/srin.199201727
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
Experimentelle Untersuchungen der Strömungen, Turbulenz und Teilraumausbildung an Kaltmodellen gasgerührter Mischreaktoren |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 387-391
Gerhard Junk,
Thomas Nonte,
Eberhard Steinmetz,
Herbert Wilhelmi,
Gereon Schlösser,
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摘要:
Im Rahmen dieser Arbeit wurden theoretische und experimentelle Untersuchungen an Wasser‐ und Quecksilbermodellen bodengeblasener Reaktoren durchgeführt, um ein mathematisches Modell zur Beschreibung der Durchmischungsvorgänge weiterzuentwickeln. Dieses mathematische Modell beruht auf der Einteilung des Gesamtsystems in Subsysteme, die als ideale Mischer miteinander im Stoffaustausch stehen. Die Strömungsverhältnisse sowie ungefähre Anzahl, Lage und Größe der Teilräume wurden unter Variation der Gasvolumenströme, der Gefäßdurchmesser und der Füllstandshöhen zunächst mit Hilfe des Lichtschnittverfahrens erfaßt. Lichtschnittuntersuchungen mit Fluoreszen als Tracer dienten zur Beobachtung des Mischverhaltens der Einzelteilräume sowie zur Bestimmung der Gesamtmischzeiten. Mit einem Laser‐Doppler‐Anemometer wurden sowohl die großräumigen als auch die lokalen Strömungs‐ und Turbulenzprofile ermittelt. Aus den so erhaltenen Daten wurden die genaue Lage und die Größe der Teilräume sowie die Stoffaustauschströme zwischen diesen bestimmt. Weiterhin wurden Konzentrationsmessungen an Quecksilbermodellen durchgeführt. Der Vergleich dieser Messungen mit den an Wassermodellen erhaltenen Strömungs‐ und Turbulenzprofilen führte zu einer Einteilung in fünf Teilsysteme, mit der bei Anwendung des mathematischen Modells gute Übereinstimmung zu gemessenen Werten erzielt werden konnte.
ISSN:0003-8962
DOI:10.1002/srin.199201728
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
Physical parameters and boundary conditions for the numerical simulation of hot forming processes |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 392-398
Reiner Kopp,
Franz‐Dieter Philipp,
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摘要:
Exact simulation of hot‐forming processes using the finite element method requires the most precise possible specification of the material parameters and physical boundary conditions prevailing in each case. The report presents a method to supply all the necessary data. New experimental concepts have been developed and applied, particularly for the more complex boundary conditions, which are virtually undocumented in literature. These techniques permit analysis of the real workpiece/interlayer/die combination, supplying reliable data for an FEM simulation.
ISSN:0003-8962
DOI:10.1002/srin.199201729
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
High‐speed temperature measurements during rapid solidification of iron‐silicon ribbons, produced by planar flow casting |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 399-404
Georg Frommeyer,
Andreas Ludwig,
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摘要:
In order to investigate the melt undercooling and the non‐equilibrium solidification of crystalline Fe 5 wt.% Si melt spun ribbons, produced by planar flow casting (PFC), high speed temperature measurements and appropriate process simulations have been performed. Using a rotating fibre optical system with a fast response double pyrometer, the temperature radiation of the solidifying ribbon during the casting process has been recorded with a measuring frequency of 50 kHz. The obtained cooling curves have been interpreted by computer simulations. It is shown that with increasing wheel temperature the overall cooling becomes more efficient. This is caused by an improved wetting behaviour of the melt‐wheel system and an increase in the heat transfer coefficient at the interface of the solidifying ribbon and the wheel from 6 · 104to about 2 · 105W/(m2K). The solidification of 100 to 200 μm thick ribbons takes place in a time interval of 2 to 5 ms. The average growth rate varies between 10 and 60 mm/s. The high cooling rate results in a fine dendritic solidification morphology with diminishing microsegregations.
ISSN:0003-8962
DOI:10.1002/srin.199201730
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Low‐cycle fatigue of X 2 NiCoMo 18 12 and X 10 NiCrAITi 32 20 |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 405-407
Klaus Detert,
Rainer Adolfs,
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摘要:
The low‐cycle fatigue and short crack‐growth behaviour of an ultra‐high strength maraging steel and a high‐nickel austenitic steel have been studied. The tests were performed in a laboratory environment at room temperature in push‐pull cycles with constant strain amplitudes of 0.25 to 2 %. Short crack‐growth investigations were performed using bending specimens loaded by a resonance bending machine. Crack growth was measured using the replica method.The cyclic and tension stress strain behaviour has been compared. Fatigue tests were interpreted according to the recommended practice of ASTM‐E 606‐80. First microcracks were observed after 10 to 70 % of the fatigue life.
ISSN:0003-8962
DOI:10.1002/srin.199201731
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
Icotom 10 |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 407-407
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ISSN:0003-8962
DOI:10.1002/srin.199201732
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
Trends in the development of grain‐oriented electrical sheet |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 408-412
Fritz Bölling,
Klaus Günther,
Andreas Böttcher,
Brigitte Hammer,
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摘要:
Thin gauge, high silicon content, perfect crystal orientation and small domain wall spacings are the fundamental features of an ideal electrical steel sheet with minimum core loss and maximum polarization. For achieving these properties in the fabrication process, very exact control of secondary recrystalliration is necessary, which becomes more and more difficult with decreasing sheet thickness and increasing silicon content. In the present paper the influence of the starting conditions – i.e. the primary recrystallized grain structure and precipitation distribution – on selective grain growth and Goss‐texture formation is described. For RGO and HGO typical differences in the primary grain size, critical inhibitor diameter and amount of primary Goss‐grains have been observed. By increasing the knowledge about the physics of electrical steel sheet, the fabrication process and magnetic properties have been continuously improved in the past. Today, new techniques of strip production like thin strip casting are an important aspect for further development offering very promising perspectives on new possibilities of texture control.
ISSN:0003-8962
DOI:10.1002/srin.199201733
出版商:Wiley
年代:2016
数据来源: WILEY
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8. |
A new approach in texture research: local orientation determination with EBSP |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 9,
2016,
Page 413-418
Olaf Engler,
Günter Gottstein,
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摘要:
A new technique for convenient measurement of crystallographic orientation of small volumes in bulk samples is introduced. It makes use of electron back scattering patterns (EBSP) in the SEM. The principle of pattern formation as well as measuring and evaluation procedure are introduced. The method offers a viable procedure for obtaining information on the spatial arrangement of orientations, i.e. on orientation topography and thus, provides a new level of information on crystallographic texture. The application of EBSP is demonstrated by two examples, namely for investigation of nucleation of recrystallization and microstructure evolution during high‐temperature fatigue.
ISSN:0003-8962
DOI:10.1002/srin.199201734
出版商:Wiley
年代:2016
数据来源: WILEY
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