1. |
Nitrogen solubility in metallurgical slags equilibrated with Fe–Al or Fe–Ca melts |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 47-59
Heike Wenz,
Dieter Janke,
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摘要:
Considerations are directed to the denitrogenation potential of metallurgical slags with respect to steel melts under reducing conditions. Experiments were made to determine partition ratios of nitrogen between molten slag and iron. The investigated systems were aluminate‐based slags, containing CaO, MgO, SrO, BaO, CaF2or ZrO2, in equilibrium with Fe–AI melts and Ca–CaO–CaF2slags equilibrated with Fe–Ca melts.Denitrogenation efficiency of aluminate‐based slags is comparatively low and essentially determined by oxygen potential and basicity of the slag. Denitrogenation efficiency of Ca–CaO–CaF2slags is much higher and is dependent on calcium activity.
ISSN:0003-8962
DOI:10.1002/srin.199200470
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
A model test for emulsion in gas–stirred ladles |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 60-68
Tianxiu Wei,
Franz Oeters,
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摘要:
At high gas‐stirring rates of liquid metals in ladles covered with slag emulsification of slag droplets into the metal melt occurs. Emulsification intensifies the rate of slag‐metal extracting reactions. A theoretical model of the emulsification process was developed. The equilibrium between buoyancy, surface, and inertial force at the location where the slag droplets are formed determines the critical liquid metal velocity for drop formation. The amount of droplets formed per time depends on the flow of kinetic energy in the thin slag layer accelerated by momentum transfer from metal to slag. Experiments on a water model were carried out to determine the drop sizes, the number of droplets formed per time and the drop flow paths. Consequences for the amount of emulsification in steel melts are drawn.
ISSN:0003-8962
DOI:10.1002/srin.199200471
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
The effect of deformation‐zone geometry on split‐ends formation in plane‐strain rolling |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 69-73
Stanislaw Turczyn,
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摘要:
Mechanism and model is proposed for split‐ends defects formation in plane‐strain rolling. An upper bound method has been chosen for this analysis and a rigid body uni‐triangular rotational velocity field was assumed for the deformation zone. Two solutions were obtained for rolling process; for sound flow and split‐ends pattern. By comparing power requirements for these cases, the whole range of rolling parameters has been divided into safe and split‐ends zone. Both perfectly plastic and strain‐hardening materials are studied. It has been found that split‐ends formation (crocodiling) is more likely to occur in thick plates and sheets when slight reduction is applied. Comparison of analytically developed criteria with data from experimental rolling of aluminium specimens shows generally good agreement.
ISSN:0003-8962
DOI:10.1002/srin.199200472
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
Geometrie der Umformzonen beim Ringwalzen |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 74-77
Ulrich Koppers,
Reiner Kopp,
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摘要:
Die Kenntnis der momentanen Umformzonengeometrie in den Walzspalten ist eine wichtige Voraussetzung und Grundlage dafür, erstmals auch beim Ringwalzen Prozeßstrategien verwirklichen zu können, die sich an definierten Anforderungen für die Umformzonengeometrie orientieren, und damit die technologischen Umformbedingungen gezielt beeinflußbar machen. Der Zusammenhang zwischen Formänderungen, Ringgeometrie und Walzengeometrie wird beschrieben, woraus sich die notwendigen Zustellgeschwindigkeiten von Dorn‐ und Kegelwalze ableiten lassen, um die geforderten Umformbedingungen on‐line einzustellen. Vielfach wird in der Produktion beim Ringwalzen auf solche Prozeßoptimierungen noch verzichtet, obwohl bei anderen „konventionellen” Umformverfahren wie Geradeauswalzen und Freiformschmieden die Prozeßabläufe sich nach solchen Kriterien orientieren. Gerade beim Ringwalzen ist durch die weltweit steigende Produktion von Ringen, z. B. für den Triebwerksbau, aus hochwertigen, teueren Superlegierungen mit den sehr engen Verfahrensgrenzen ein neues Optimierungsfeld entstanden.
ISSN:0003-8962
DOI:10.1002/srin.199200473
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Hot workability of M2 type high‐speed steel |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 78-84
Ranko Milović,
Dragoslav Manojlović,
Milojica Andjelić,
Djordje Drobnjak,
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摘要:
The hot workability of an M2 type HSS in cast, forged and rolled condition has been studied by means of a torsion test and metallography. Continuous tests were used to determine the temperature and strain‐rate dependence of the flow stress and temperature dependence of the strain to fracture, while multistage tests were used to determine the extent of interpass softening.Temperature and strain dependence of the flow stress is described by a relation of the form:in which the activation energy for hot working (QHW) is found to be temperature dependent. The hot ductility of the cast steel is not only lower but is also little affected by temperature in comparison to worked steels, in spite of the fact that critical strain for dynamic recrystallization is smaller, and the extent of metadynamic and static recrystallization during interpass interval is more extensive in the former. This is related to a large volume fraction of carbides, which give rise to a high stored energy and enhanced recrystallization on the one hand, and to the suppression of recrystallization within the continuous network of carbides on the other hand. Carbides give rise to an easy nucleation, growth and coalescence of cracks.
ISSN:0003-8962
DOI:10.1002/srin.199200474
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
ECSC announcements |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 84-84
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ISSN:0003-8962
DOI:10.1002/srin.199200475
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
The corrosion behaviour of Cr/Co/Mo‐alloyed low residual carbon steels in seawater solutions |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 85-91
Jamal N. Al‐Hajji,
Mahmoud Rajab Reda,
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摘要:
The general corrosion behaviour of low residual steels alloyed with chromium or cobalt or molybdenum in seawater solutions was studied. The carbon content of low residual steels ranged from 0.1 to 0.4%, chromium content between 1.0 and 4.0%, cobalt content between 1.0 and 3.0%, and molybdenum content between 0.3 and 1.0%. Repeated laboratory tests demonstrated that low levels of chromium reduce the dissolution rate of low residual steels in seawater solutions. The results of this study suggest that cobalt alloying plays a neutral role, whereas molybdenum plays a major role in reducing the corrosion rates, particularly in higher carbon steels.
ISSN:0003-8962
DOI:10.1002/srin.199200476
出版商:Wiley
年代:2016
数据来源: WILEY
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8. |
News from the Max‐Planck‐Institut für Eisenforschung GmbH |
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Archiv für das Eisenhüttenwesen,
Volume 63,
Issue 2,
2016,
Page 92-92
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ISSN:0003-8962
DOI:10.1002/srin.199200477
出版商:Wiley
年代:2016
数据来源: WILEY
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