1. |
Research and Development of the British Steel Corporation |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 451-456
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ISSN:0003-8962
DOI:10.1002/srin.198500665
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
Studies on the removal of phosphorus and sulfur from Fe‐C and Fe‐C‐Mn melts at 1350°C |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 457-464
Josef Parys,
Alberto R. Romero,
Johann‐C. Wrampelmeyer,
Dieter Janke,
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摘要:
Laboratory studies have been performed on simultaneous dephosphorization and desulfurization of Si‐free Fe‐4.5 % C melts with [P]o= 0.11 wt.% and [S]o= 0.04 wt.% in MF induction furnaces at 1 350°C. In these investigations, CaO‐ or Na2CO3‐based fluxes were used and the techniques of powder injection or single top slag addition were applied.The following results have been obtained:– The effectiveness of lime and soda‐based fluxes with regard to dephosphorization is practically the same. But a lower sulfur level is attained when Na2CO3‐based fluxes are used.– In the injection experiments, efficiencies of ηP= 80% for dephosphorization and ηs= 90% for desulfurization are easily reached at a powder consumption of 50 to 60 g/kg. But a further increase of the η values requires a remarkable increase in the amount of injected powder. Top slag addition instead of powder injection is less effective, in general.– Apparent rate constantsk[P]andk[S]from 0.05 to 0.3 min−1have been determined in the initial stage of injection depending on the relative amount of injected flux. In the top slag experiments, thek[P]andk[S]values were practically constant at a level of 0.1 min−1.Furthermore, dephosphorization of molten Fe‐C‐Mn alloys at 1 350°C has been studied at variable Mn content. It is predicted from thermodynamic data and confirmed by experiments that dephosphorization lessens with increasing Mn content in the range from 0 to 15 wt.%.
ISSN:0003-8962
DOI:10.1002/srin.198500666
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
On the smelting reduction of iron ores with hydrogen‐argon plasma |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 465-469
Michael Lemperle,
Alfred Weigel,
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摘要:
Investigations of the plasma smelting reduction of iron ore have been carried out on a laboratory scale using a transferred argon‐hydrogen plasma arc. Pyrometric measurements show that the surface temperature near the arc foot is about 2600 K when the hydrogen is mixed with the plasma‐gas in front of the cathode, about 2250 K when the hydrogen is introduced laterally into the arc and ca. 2150 K when a pure argon plasma is used. With the help of thermodynamic plasma data the corresponding arc temperatures have been estimated to be 13 000 K, 11000 K and 9500 K. It has been shown that the reduction rate after the smelting phase remains constant and is practically independent of the manner of addition of the hydrogen. The measured efficiencies of utilization of hydrogen were 43% and 50% and thus correspond closely to the equilibrium FeO + H2= Fe + H2O. A combination of the rate constants obtained for the plasma smelting reduction with those found in literature for lower temperatures leads to an activation energy of approximately 67 kJ/mol. This value lies in the range of energies reported for the reduction of wustite after precipitation of the iron phase. It is therefore not unlikely, that in the case of plasma smelting reduction also, the rate determining step is the reaction Had+OHad→ H2Oad.
ISSN:0003-8962
DOI:10.1002/srin.198500667
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
Information on research and development |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 470-470
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ISSN:0003-8962
DOI:10.1002/srin.198500668
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Zerteilung einer Eisenschmelze in Tropfenketten mit Hilfe einer Druckdüse |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 471-476
Jürgen Ganzow,
Klaus Koch,
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摘要:
Im Rahmen von Untersuchungen zum Stoffübergang von Mangan aus Eisentropfen in hoch‐FeOn‐haltige Schlacken ist eine gezielte Erzeugung von Einzeltropfen und Tropfenketten mit definierten Partikeldurchmessern notwendig. Hierzu wurde als Versuchseinrichtung zur Zerteilung einer Eisenschmelze eine Druckdüse verwendet. Bei Kapillardurchmessern um 0,6 mm weisen 80 bis 90% der erzeugten Partikeln im festen Zustand nur eine geringe Streuung ihrer Durchmesserum den häufigsten Wert von knapp 3,9 mm auf. Für 1600°C lassen sich damit der mittlere kugeläquivalente Tropfendurchmesser zu 4 mm und die spezifische Oberfläche zu 0,216 m2kg−1berechnen. Schwierigkeiten bei der Erzeugung von definierten Tropfenketten mit noch kleineren Fragmenten werden erläutert.
ISSN:0003-8962
DOI:10.1002/srin.198500669
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
Grain refinement of microalloyed austenite due to statical recrystallization after hot deformation |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 477-481
Radko Kaspar,
Oskar Pawelski,
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摘要:
In a microalloyed Nb‐Mo steel the austenite structure was evaluated. For hot compression tests in the temperature region of 1000–1150°C with subsequent complete statical recrystallization the hot deformation simulator (WUMSI) was employed. Effects of initial austenite grain size, strain and deformation temperature on recrystallized austenite structure were established. The results emphasize the controlling role of potential nucleation sites. The single deformation study was supplemented by some multiple deformation tests and common guidelines were formulated.
ISSN:0003-8962
DOI:10.1002/srin.198500670
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
The effect of fine precipitate particles on the creep behaviour of ferritic model steels ‐I. Experiments |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 483-488
Jürgen Peterseim,
Gerhard Sauthoff,
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摘要:
In view of efforts to develop ferritic creep resistant steels for applications above 600°C the effect of fine precipitate particles on the creep behaviour of ferritic model steels was studied as a function of stress, temperature and particle distribution. The chosen model steels contained 20% Cr (by mass), up to 0.9% Nb and up to 0.1 % C to produce NbC volume fractions up to 0.8% with particle sizes of about 0.1 μm (order of magnitude). The alloys and structures are briefly described (NbC solubility, precipitation and ageing behaviour, recrystallization and grain growth, oxidation resistance) as well as the mechanical short‐term behaviour. The creep behaviour was studied between 600°C and 800°C (with emphasis on 700°C) at strain rates between 10−11and 10−6s−1with times to rupture up to 20000 h. The creep resistance of the model steels at 700°C (for a strain rate of 10−8s−1) increases with increasing NbC content from about 5 MN/m2for the alloy without NbC to about 50 MN/m2for the alloys with 0.6% or 0.8% NbC. The analysis of the obtained results is the subject of the second part of this report.
ISSN:0003-8962
DOI:10.1002/srin.198500671
出版商:Wiley
年代:2016
数据来源: WILEY
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8. |
Measuring of the quenching effect of liquid hardening agents on the basis of synthetics |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 489-495
Hans M. Tensi,
Ernst Steffen,
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摘要:
To judge liquids for steel hardening, normally special test specimens are quenched by means of immersion. Characteristics are taken from temperature‐time curves, which are picked up in the sample center. These characteristics (i.e. temperature of transition from filmboiling to nucleate boiling – LEIDENFROST‐Temperature – and cooling rates) serve as criterions for the judgement of quenching effect.The effect of sample characteristics (geometry and material) upon characteristic values of the cooling curve was determined. Hence a proposal to design a test specimen was derived. This specimen (Chromenickel‐steel‐cylinder, diameter 15 mm, length 45 mm, rounded edges) presents of all examined configurations a very good possibility to a precise judgement of quenching media as well as chances to estimate the quenching process in case of steel hardening.As common quenching tests (with a single – central – hot junction) do not allow to draw conclusions referring to steel hardening, an additional method was developed to calculate the surface‐temperature dependent heatflux density (respectively heattransfer coefficient) from three temperature‐time‐curves, measured on different radii of the sample cylinder. The reliability of this method was proved (differential method according to Binder‐Schmidt).
ISSN:0003-8962
DOI:10.1002/srin.198500672
出版商:Wiley
年代:2016
数据来源: WILEY
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9. |
News from the Max‐Planck‐Institut für Eisenforschung GmbH |
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Archiv für das Eisenhüttenwesen,
Volume 56,
Issue 9,
2016,
Page 496-496
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PDF (241KB)
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ISSN:0003-8962
DOI:10.1002/srin.198500673
出版商:Wiley
年代:2016
数据来源: WILEY
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