1. |
Modellmäßige Beschreibung des Temperaturfeldes eines Sinterprozesses |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 333-338
Eckart Streich,
Bodo Hesse,
Heinrich‐Wilhelm Gudenau,
Preview
|
PDF (568KB)
|
|
摘要:
Im Rahmen einer Dissertation stellte sich die Aufgabe, die Partikelfiltration in einem Sinterprozeß modellmäßig zu beschreiben, der von Sinterabgas durchströmt wird. Dazu wurde ein Modell des Temperaturfeldes im Sinterprozeß entwickelt. Die Beschreibung dieses Temperaturmodells wird in dieser Arbeit ausführlicher als in der Dissertation dargestellt.Ausgehend von der Differentialgleichung für den Wärmetransport wird mit vorgegebenen, idealisierenden Modellannahmen eine analytische Lösung gefunden, mit der der örtliche und zeitliche Temperaturverlauf des Sinterprozesses berechnet werden kann. Beim Vergleich von gemessenen Temperaturdaten und berechneten Modellwerten wird eine gute Übereinstimmung festgestellt. Neben der Überprüfung von Parametereinflüssen ist das Modell auch zur Überprüfung von numerischen Modellansätzen geeignet.
ISSN:0003-8962
DOI:10.1002/srin.199000358
出版商:Wiley
年代:2016
数据来源: WILEY
|
2. |
Mass transfer between solid and liquid in vessels agitated by bubble plume |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 339-346
Dipak Mazumdar,
Srikanth K. Kajani,
Ahindra Ghosh,
Preview
|
PDF (788KB)
|
|
摘要:
Mass transfer from solid benzoic acid cylinders to a gas‐stirred aqueous bath has been investigated both theoretically and experimentally. Two typical gas injection configurations, the conventional central injection and the C.A.S. (CompositionAdjustment bySealed Argon Bubbling) were employed and the rates of dissolution of the acid compacts at various locations in the bath were measured at different gas‐flow rates. These demonstrated that the mass‐transfer rates are the highest in the two‐phase region, while elsewhere in the bath, these were found to be practically identical. Furthermore, mass‐transfer rates at the corresponding locations were found to be relatively greater for the conventional central injection than those for the C.A.S. configuration.Distribution of velocity and turbulence intensity in the vessel were computed theoretically using a previously reported calculation procedure. Based on these, values of various relevant dimensionless numbers were estimated so as to assess the adequacy and effectiveness of heat and mass‐transfer correlations reported in the literature. These, however, did not fit with the present experimental observations. For this reason, a new correlation has, therefore, been proposed and it is shown that the experimental data can be described reasonably well by the equationSh= 0.73 (Reloc,r)0.57(Ti)0.32(Sc)0.3. This correlation also embodies more plausible definitions of Reynolds number (Reloc,r) and the turbulence intensity (Ti) in contrast to those reported in literature, since it has been derived using the local resultant mean velocity and the local fluctuating velocity in the fluid.
ISSN:0003-8962
DOI:10.1002/srin.199000359
出版商:Wiley
年代:2016
数据来源: WILEY
|
3. |
The application of optical basicity to dephosphorization equilibria |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 347-352
Åke Bergman,
Preview
|
PDF (513KB)
|
|
摘要:
Es werden Ergebnisse dargestellt, die zeigen, daß die optical basicity of metallurgical slags. Optical basicity is applied to phosphate capacity data and optical basicity is found to be a very sensible measure of basicity. The application of optical basicity to CaO‐saturated slags is examined and discussed.
ISSN:0003-8962
DOI:10.1002/srin.199000360
出版商:Wiley
年代:2016
数据来源: WILEY
|
4. |
Experimental studies on hydrogen solubility in liquid ternary iron‐nickel‐chromium alloys |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 353-358
Mandaresh Mitra,
Klaus W. Lange (†),
Preview
|
PDF (573KB)
|
|
摘要:
The hydrogen solubilities in liquid ternary iron‐nickel‐chromium alloys have been experimentally determined by Sieverts’ method. The experimental data have been evaluated with the help of regression analysis (Gauß‐Jordan) and using own published empirical equations (polynomials). With the help of experimentally determined hydrogen solubilities and the coefficients of the polynomials, the concentration dependencies of hydrogen solubilities, interaction coefficients, enthalpies and entropies of hydrogen solution have been determined.The hydrogen solubility increases with increasing temperature and with an increase in the nickel and chromium concentration. The results have been represented as isothermal planes. The hydrogen solubilities in liquid ternary iron‐nickel‐chromium alloys (xCr≤ 50%) have been predicted with the help of “Central Atoms” model, assuming the concentration dependencies of the “model parameter λ” and selecting the value of the coordination number (Z’ = 10) for each of the “reference elements” iron or nickel.The comparison between the experimentally determined and the predicted hydrogen solubilities in iron‐nickel‐chromium alloys confirms that the prediction of hydrogen solubilities in liquid system iron‐nickel‐chromium can be qualitatively made over a wide range of alloy concentrations (xCr= 50%) with the aid of “Central Atoms” model and with the assumption of concentration dependencies of the “model parameter λ”.
ISSN:0003-8962
DOI:10.1002/srin.199000361
出版商:Wiley
年代:2016
数据来源: WILEY
|
5. |
Some aspects of development of models for automatic control of rolling mills |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 359-364
Maciej Pietrzyk,
Jan Kusiak,
Miroslaw Glowacki,
Preview
|
PDF (508KB)
|
|
摘要:
Computer‐aided rolling‐technology design is presented in the paper. Program is based on the solution of the set of non‐linear equations which describe the process. They include continuity equations and power balance equations for continuous rolling. Reverse rolling is described by constant‐rolling‐force equations and power‐balance equations for both main drive and reel drives. Typical results of calculations for hot and cold rolling processes are presented.
ISSN:0003-8962
DOI:10.1002/srin.199000362
出版商:Wiley
年代:2016
数据来源: WILEY
|
6. |
Method for determination of the basic stand characteristics of rolling mill |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 365-368
Günter Uetz,
Preview
|
PDF (314KB)
|
|
摘要:
Higher demands towards the accuracy of the thickness of hot‐rolled strip require a description in the most exact possible way of the roll‐gap ratio for the determination of the idle roll gap as well as for the load roll gap control system. Doing so, exact knowledge of the roll‐spring response of the rolling stand is a necessary prerequisite. Examinations of the real roll‐spring response in various stands with different roll sets have disclosed that recording the spring‐off response after each change of work rolls or support rolls is indispensable. On the grounds of this examination, a procedure for the determination of the basic stand characteristic was developed which approximates the real roll‐spring behaviour in the best possible way.
ISSN:0003-8962
DOI:10.1002/srin.199000363
出版商:Wiley
年代:2016
数据来源: WILEY
|
7. |
A mathematical model for flat rolling of austenitic steel at elevated temperatures |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 369-375
Stanislaw Turczyn,
Zbigniew Kuzminski,
Andrzej Nowakowski,
Preview
|
PDF (553KB)
|
|
摘要:
The paper is concerned with the mathematical model for the computation of the technological as well as force and energy parameters during rolling of austenitic steel sheets and strips at elevated temperatures. On the basis of the computation results obtained for 18–8 type chromium‐nickel steel (marked 1H18N9T) universal nomograms have been designed for a wide range of strip width and roll diameters. They allow the evaluation of force parameters, energy consumption and average temperature in the roll pass depending on the reduction and strip initial temperature as well as strip relative thickness. The presented nomograms might be helpful in designing the technology for warm rolling of austenitic steel sheets and strips as well as conventional cold‐rolling, taking into consideration thermal effects in the deformation zone.
ISSN:0003-8962
DOI:10.1002/srin.199000364
出版商:Wiley
年代:2016
数据来源: WILEY
|
8. |
Formation of textures in a C–Si–V dual‐phase steel |
|
Archiv für das Eisenhüttenwesen,
Volume 61,
Issue 8,
2016,
Page 376-384
Dipak Kumar Mondai,
Ranjit Kumar Ray,
Preview
|
PDF (958KB)
|
|
摘要:
A vanadium microalloyed steel (0.1 C, 1.50 Si, 0.1 V) was subjected to initial heat treatments and intercritical annealing at 750 and 810°C to produce dual‐phase structures of different distribution. Intercritically annealed materials were cold‐rolled to a reduction of 60% in thickness and small samples taken from them were recrystallisation annealed at two temperatures of 650 and 800°C for various lengths of time. The (110) pole‐figures for the cold‐rolled materials with different dual‐phase distribution showed a strong {111}and a rather weak {111}texture components. The O.D.F. (orientation distribution function) plots also showed the major texture components, {111}and {111}along with the minor components, like, {337}, {337}, {112}and {112}. No complete {111} fibre has been observed in the present investigation. Further the orientations{11, 11,4}and {337}have been found to be present as weak and incomplete fibre. The (110) pole‐figures of the recrystallised materials have shown similar features (with reduced pole densities) as compared to the cold‐deformed materials. Similarly, no {111} fibre has been observed in the recrystallised materials. The behaviour of the other two components, namely {11, 11,4}, and {337}have been found to be similar to that in the cold deformed material.
ISSN:0003-8962
DOI:10.1002/srin.199000365
出版商:Wiley
年代:2016
数据来源: WILEY
|