1. |
Possible failure of emf oxygen sensor in liquid iron containing dissolved calcium or magnesium |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 379-382
Ethem Tugrul Turkdogan,
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摘要:
The solubility products of CaO and MgO in liquid iron, measured using the emf oxygen sensor, are several orders of magnitude greater than those calculated from the thermochemical data. This would imply that the values of Δ and Δ derived from the solubility products are, by a large amount, less negative than those given in the compiled thermochemical tables. As is shown in this paper, the values of Δ derived indirectly from numerous experimental data on various gas‐solid (‐liquid) reactions involving pure CaO, are in general accord with the compiled thermochemical data. It is surmised from these observations that the oxygen activities in liquid iron saturated with CaO or MgO, measured by the emf cell, giving high solubility products of CaO and MgO, may be attributed to the failure of the emf oxygen sensor in liquid iron containing dissolved calcium or magnesium. Two reaction mechanisms are discussed in the paper to account for the malfunction of the oxygen sensor under highly reducing conditions, which will prevail in liquid iron containing even a small amount of dissolved calcium or magnesium. These two mechanisms are (i) redox reaction at the (Y2O3)ThO2electrolyte/melt interface and (ii) oxygen flux through the electrolyte from the reference electrode Cr–Cr2O3to the melt/electrolyte interface. Suggestions are made for some experimental work to confirm or refute the argument presented in this communication.
ISSN:0003-8962
DOI:10.1002/srin.199101314
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
Comments on “Possible failure of emf oxygen sensor in liquid iron containing dissolved calcium or magnesium” |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 382-383
Philip J. Spencer,
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ISSN:0003-8962
DOI:10.1002/srin.199101315
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
Comments on “Possible failure of emf oxygen sensor in liquid iron containing dissolved calcium or magnesium” |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 383-384
Dieter Janke,
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ISSN:0003-8962
DOI:10.1002/srin.199101316
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
Estimation of partial excess Gibbs energy of solutes in infinitely dilute liquid iron base binary alloys |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 385-389
Toshihiro Tanaka,
Nev A. Gokcen,
Dieter Neuschütz,
Philip J. Spencer,
Zen‐ichiro Morita,
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摘要:
The partial excess Gibbs energy ΔḠBExas well as the relationship between the partial enthalpy of mixing ΔH̄Band the partial excess entropy of solution ΔS̄BExof various solute elements in liquid Fe, Al and Pb binary alloys were evaluated from a new solution model, in which ΔS̄BExcan be calculated from the values of ΔH̄Bby Miedema's semi‐empirical method and some relevant physical properties of the components in the alloys. These calculated values of ΔḠBExwere found to be in reasonable agreement with the selected values presented so far. The present model gives the values of ΔḠBEx, for which the experimental data are not yet available.
ISSN:0003-8962
DOI:10.1002/srin.199101317
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Metallurgical results from a 30‐t AC plasma ladle furnace |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 390-394
Dieter Neuschütz,
Karl‐Heinz Schubert,
Hans J. Bebber,
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摘要:
In a 30‐t ladle furnace equipped with three A.C. transferred arc‐plasma torches for a power input of 6 MW, the influence of argon plasma heating on the chemical composition of a number of steel grades from carbon to chromium‐nickel steels was investigated. The concentrations of carbon, manganese, chromium and nickel remained virtually constant even for extra‐long heating periods of 2 hours. Silicon melting loss was appr. 0.03%/h, comparable to conventional ladle furnaces. Nitrogen pickup proved to be negligibly small, although the N2partial pressure in the furnace was about 0.5 bar. Since the slag is well heated up by the plasma flames, a metal desulphurization is noticed, the extent of which depends on the basicity of the slag. At the slag/gas interface, equilibrium is established with the slightly oxidizing furnace atmosphere, leading to sulphur transfer from slag to gas via SO2.
ISSN:0003-8962
DOI:10.1002/srin.199101318
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
Experiments on the development of non‐oxidizing fluxes for continuous steel casting |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 395-404
Peter Hammerschmid,
Dieter Janke,
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摘要:
An attempt has been made to eliminate easily reducible oxide components, such as SiO2, TiO2, alkaline oxides and Fe2O3and thereby exclude oxygen sources from casting fluxes. The new casting fluxes are based on CaO, Al2O3, MgO, SrO with limited amounts of alkaline and alkaline earth fluorides. Melting behaviour, viscosity, Al2O3solubility and wear of submerged nozzles is essentially the same as that of conventional casting fluxes. The new fluxes also tend to undergo glassy solidification.
ISSN:0003-8962
DOI:10.1002/srin.199101319
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
Improvement of mechanical properties of pearlitic and pearlitic‐ferritic steels by deformation‐induced changes of microstructure |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 405-411
Radko Kaspar,
Hans‐Jörg Gasterich,
Karl Edgar Hagedorn,
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摘要:
By using laboratory simulation tests thermomechanical processing, based on a post‐transformation hot deformation with accelerated cooling, was employed on two steels with 0.46 and 0.76% C. Finer pearlite interlamellar spacing, reduced proeutectoid ferrite, and partially spheroidized pearlite bring about a substantial increase of strength without loss of toughness and ductility.
ISSN:0003-8962
DOI:10.1002/srin.199101320
出版商:Wiley
年代:2016
数据来源: WILEY
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8. |
Entwicklung, Eigenschaften und Anwendung von konventionell erzeugten hochstickstoffhaltigen austenitischen Stählen |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 412-420
Christoph Gillessen,
Winfried Heimann,
Thomas L. Ladwein,
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摘要:
Durch legierungstechnische Maßnahmen lassen sich mit konventionellen Verfahren (Elektrolichtbogenofen, AOD‐/VOD‐Anlage) hochstickstoffhaltige austenitische Stähle erzeugen, die im lösungsgeglühten Zustand beachtliche Eigenschaften aufweisen. Die Wirkungen des Stickstoffs sind eine Erhöhung der Festigkeit durch Mischkristallverfestigung (und Auscheidungshärtung bei Amagnit 3974 (X 3 CrNiMnMoNbN 23 17 5 3)), eine Erhöhung der Austenitstabilität, die Verzögerung von Ausscheidungsvorgängen sowie eine Verbesserung der Loch‐ und Spaltkorrosionsbeständigkeit.Nach der Entwicklung von hochfesten unmagnetischen Stählen führte die Legierungsoptimierung zu dem Werkstoff Remanit 4565 S (X 2 CrNiMnMoN 24 17 6 4), der bei hoher Festigkeit eine ausgezeichnete Beständigkeit in zahlreichen Medien aufweist. Aufgrund des günstigen Einflusses von Stickstoff weist dieser Stahl mit nur 4,5 % Molybdän eine höhere Wirksumme PRE und eine höhere Beständigkeit gegen Loch‐ und Spaltkorrosion auf als die gängigen 6%‐Mo‐Austenite. Das Schweißen der beschriebenen hochstickstoffhaltigen Stähle ist ohne besondere Vorkehrungen mit allen üblichen Verfahren möglich. Porenbildung tritt nicht auf. Mit dem empfohlenen Schweißzusatz Thermanit NimoC (SG‐NiCr 20 Mo 15) lassen sich mit dem WIG‐ und dem UP‐Schweißen an Remanit 4565 S (X 2 CrNiMnMoN 24 17 6 4) Verbindungen herstellen, die ebenso beständig gegen Loch‐ und Spaltkorrosion sind wie der Grundwerkstoff. Somit steht mit Remanit 4565 S (X 2 CrNiMnMoN 24 17 6 4) eine vielseitige wirtschaftliche Alternative zu 6 %‐Mo‐Stählen und Nickelbasislegierungen zur Verfügung.
ISSN:0003-8962
DOI:10.1002/srin.199101321
出版商:Wiley
年代:2016
数据来源: WILEY
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9. |
Physical properties in the temperature range from –180 to 400°C of nickel alloy steels for low‐temperature applications |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 421-425
Friedhelm Richter,
Wolfgang Hemminger,
Erich Hanitzsch,
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摘要:
Nickel, which is the second neighbour to iron in the periodic table of elements, has a significant effect on most of the physical properties of the steels studied here, with the nickel content of the steels varying between 3 and 9%. Density and coercive force increase as the nickel content in the steel increases. By contrast, thermal expansion, modulus of elasticity and shear modulus decrease with increasing nickel content.Because of large scatter in the data, it is not possible to notice any significant influence of nickel content on Poisson's ratio and bulk modulus. Specific heat is also found not to vary with the nickel content of the steel. Electrical resistivity and thermal resistivity values increase, as expected, with increasing nickel content. The results of thermal conductivity measurements on 12 Ni 19 and X 8 Ni 9 have led to the development of modified Smith‐Palmer relationships, which allow the calculation of the thermal conductivity values for the present set of steels and other steels with similar compositions.
ISSN:0003-8962
DOI:10.1002/srin.199101322
出版商:Wiley
年代:2016
数据来源: WILEY
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10. |
News from the Max‐Planck‐Institut für Eisenforschung GmbH |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 9,
2016,
Page 426-426
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ISSN:0003-8962
DOI:10.1002/srin.199101323
出版商:Wiley
年代:2016
数据来源: WILEY
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