1. |
Artificial neural nets for prediction of silicon content of blast furnace hot metal |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 521-527
Himanshu Singh,
Nallamali Venkata Sridhar,
Brahma Deo,
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摘要:
Conventional models for prediction of silicon content of blast furnace hot metal are briefly reviewed. Four different artificial neural net (ANN) models, namely, back propagation algorithm (BPA), dynamic learning rate algorithm, functional link network (FLN) and fuzzy neural network (FNN), are trained and tested on operational data from blast furnace (BF1) at Visakhapatnam Steel Plant. FNN can predict silicon mass content of hot metal with a standard error (actual versus predicted) of 0.09% and correlation coefficient of 0.86; standard back propagation predicts with a standard error of 0.08 % and correlation coefficient of 0.79.
ISSN:0003-8962
DOI:10.1002/srin.199605531
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
Measurement of aluminum or silicon activity in Fe‐Ni (<30 %) alloys using mullite and ZrO2‐based solid electrolyte galvanic cell |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 528-536
Guangqiang Li,
Ryo Inoue,
Hideaki Suito,
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摘要:
Using mullite (3Al2O3·2SiO2)‐tube type and ZrO2(MgO mole fractions of 9 %)‐plug type solid electrolyte, the activities of Al in the Fe‐15, 29% Ni‐0.002 to 0.84% Al (mass contents in%) alloys were measured at 1873 K in an Al2O3crucible, and those of Si in the Fe‐13, 28% Ni‐0.13 to 2.3% Si alloys were measured at 1823 K in a mullite crucible with an excess of SiO2. The interaction coefficients ofandwere determined as −0.0173 ± 0.0052 and 0.00021 ± 0.00007, respectively, and those ofandwere determined as 0.0094 ± 0.0049 and −0.00008 ± 0.00004, respectively. The oxygen activities obtained by the EMF measurements were compared with those obtained from the contents of analyzed oxygen. The oxygen activities in the Fe‐Ni‐Alalloys were found to be supersaturated. The interaction coefficients ofandwere determined as 0.0027 ± 0.0012 and 0.00012 ± 0.00004, respectively, from the contents of analyzed oxygen in Fe‐Ni‐Sialloys.
ISSN:0003-8962
DOI:10.1002/srin.199605532
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
Development of a new ceramic inclusion separator for steel melts |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 537-542
Klaus Raiber,
Jan Hantusch,
Peter Hammerschmid,
Dieter Janke,
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摘要:
The majority of steels produced by continuous casting is fully Al‐killed. Ceramic foam and multi hole filters have been tested so far in laboratory and small scale production experiments to lower the total oxygen content of steel melts. The use of such filters in tundishes has hitherto been limited by their insuffiicient mechanical and thermal durability over extended periods. Owing to their small pore sizes, these filters allow a high inclusion separation efficiency, but a limited mass throughput. Therefore a technique is looked for to extract non‐metallic inclusions efficiently from the melt at higher mass throughputs. Further ideas led to a new ceramic inclusion separator which has been tested in small scale experimental runs. To verify the flow and separation process, a water model has been built and numerical modelling was applied. The results of the molten steel experiments, the water model and the mathematical modelling are described and compared to each other. For the small scale it is confirmed that the new experimental device may yield high filtration efficiencies.
ISSN:0003-8962
DOI:10.1002/srin.199605533
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
Effects of medium‐ and low‐temperature carbides on the mechanical properties of a low‐carbon steel |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 543-548
Aiwu Zhu,
Andreas Meyr,
Erwin Pink,
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摘要:
A steel with low mass contents of carbon (0.04 %) was quenched and aged at temperatures between 60 and 200°C. The increase in yield stress due to these aging treatments and other mechanical properties were analyzed. A rather direct correlation of results from internal friction with those for yielding exists. The precipitates which form during aging at the lowest temperatures are equally capable of improving the yield stress. Thus it is possible to improve the properties by modified “bake‐hardening”. Comparisons with literature confirmed that the aging procedures influence the kinetics of precipitation and the resulting strength increase: intermediate aging at room temperature before the proper aging treatment are of advantage.
ISSN:0003-8962
DOI:10.1002/srin.199605534
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Fatigue crack propagation near fatigue threshold in various structural steels |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 549-554
Seungho Han,
Patrick Reinhold,
Markus Ring,
Winfried Dahl,
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摘要:
The investigations have been conducted by measuring fatigue crack propagation near fatigue threshold in various structural steels differing in chemical composition and strength level. The fatigue crack propagation measurements were carried out using the constant‐load‐amplitude test in Paris‐region,R‐constant andKmax‐constant method in near fatigue threshold region. Scanning electron microscopy at fatigue crack front on fracture surface was applied to interpret the influence of crack closure effects on the measured fatigue threshold. Marked fretting oxide deposits distributed on the fracture surface at threshold level were observed in a low load ratio resulting from the combined action of plasticity‐ and oxide‐induced crack closure under laboratory atmosphere. Fatigue threshold dependent on the load ratio appeared to be related to the extent of the crack closure effect. By considering the relationship of reversed plastic zone size and grain size the fatigue threshold in region of crack closure was calculated theoretically. The result has shown a good agreement with the experimentally measured values.
ISSN:0003-8962
DOI:10.1002/srin.199605535
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
Dynamic fracture behaviour of simulated weld heat affected zone of a high strength low alloy steel |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 555-557
Wei‐Sheng Lei,
Yan Su,
Mei Yao,
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摘要:
Fracture toughness properties of a simulated weld coarse grain heat affected zone (CGHAZ) in a newly developed 785 MPa grade high strength low alloy (HSLA) steel were investigated at different loading rates and a series of temperatures. It is indicated that the fracture toughnessKIcis a single‐value function of the parameter ΔH=kTIn (A/ε̇), implying that just like the plastic deformation, the event of fracture initiation is also controlled by dislocation thermal activation movement.
ISSN:0003-8962
DOI:10.1002/srin.199605536
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
Prediction of metallic materials creep deformation under multiaxial stress state |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 558-564
Nikolaos D. Batsoulas,
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摘要:
A simple function of multiaxial creep is presented hereafter. This is derived from a uniaxial creep function with only three fitting parameters. For the derivation of the multiaxial function the only assumption made was the one of material's isotropy. With the additional assumption of constant volume, the function leads to a v. Mises‐type function of multiaxial creep. The equivalent stress employed has a simple form as well and leads to the v. Mises equivalent stress. The derived curves agree with the experiments, not only the ones carried out in the laboratory but also the ones taken from literature.
ISSN:0003-8962
DOI:10.1002/srin.199605537
出版商:Wiley
年代:2016
数据来源: WILEY
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8. |
Hydrogen permeation through oxide and passive films on iron |
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Archiv für das Eisenhüttenwesen,
Volume 67,
Issue 12,
2016,
Page 565-572
Karen Schomberg,
Hans Jürgen Grabke,
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摘要:
Hydrogen permeation through thin films of FeI–YO on iron and through chemically polished iron were investigated by the sensitive electrochemical technique. The oxide was formed on the exit side of the sample membrane. The hydrogen arriving at the iron/oxide interface is in an atomic or protonic state which renders the hydrogen uptake by the oxide possible.The wustite films were formed by oxidation in a H2O‐H2‐atmosphere. The dependence of the hydrogen permeation current on temperature and film thickness and different degrees of nonstoichiometry in FeI–YO was studied. Hydrogen permeation through these oxides is possible, but very low permeation coefficients have been found, of the magnitude ofat 25°C. The diffusion coefficient of diffusible hydrogen was determined to be about 4 · 10−10cm2/s. Measurements of the potential dependence of permeation across the film indicate that hydrogen migrates in the oxide as a charged particle (proton).In the case of the passive surface film on iron formed by chemical polishing, the dependence of the permeation current on temperature and anodic potential was measured. The electrochemical behaviour of the film was studied by cyclic voltametry. Electron transfer reactions were investigated by means of the hexacyanoferrate (II/III) redox system. Further information on the film composition were obtained by Auger electron spectroscopy. On the one hand, electron transfer across the film can occur, but on the other hand, the film is nearly impermeable for hydrogen, even if the hydrogen is in the atomic or protonic state. Cyclic voltamograms show the formation of an oxygen adsorption layer on the film in a range of anodic potential.
ISSN:0003-8962
DOI:10.1002/srin.199605538
出版商:Wiley
年代:2016
数据来源: WILEY
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