1. |
Thermodynamics of manganese distribution between liquid iron and the CaO–Al2O3–SiO2–FeO–MnO system |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 281-284
Aleš Mališ,
Šárka Langová,
Juraj Leško,
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摘要:
The thermodynamics of distribution of constituents between liquid iron and the CaO–Al2O3–SiO2–FeO–MnO system at 1600°C was studied using electrochemical indication of the equilibrium partial pressure of oxygen in both phases. The results show that oxidation potential of the Fe(l)–CaO–Al2O3–SiO2–FeO–MnO system, expressed in terms of logp(O2), is directly proportional to log (x(MnO) ·x(FeO)/w| Mn |). Manganese distribution coefficient,L'mn, in intersection CaO/Al2O3= 1 decreases with increasing slag basicity expressed in terms of activitya(CaO) or 1/γ(MnO). Experimentally determined equilibrium constantKMn/Feis equal to 2.7 for 1600°C. The number of exchanged electrons between Fe‐O‐Mn‐Si electrode and the slag approaches the theoretical value.
ISSN:0003-8962
DOI:10.1002/srin.199101295
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
Fundamental thermodynamic aspects of the CaO–Al2O3–SiO2system |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 285-288
Blaženko Koroušić,
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摘要:
The most important metallurgical effects of ladle treatment of aluminium‐killed steels with calcium, are associated with the modification of alumina inclusion. For the development of the deoxidation‐control model for inclusions, the thermodynamic slag model, based on the Gibbs energy minimization and modelling approaches postulated from J. Hastie et al., was used to calculate component oxide activities in the system CaO–Al2O3and part of systems 3CaO · Al2O3– SiO2, 12 CaO · 7Al2O3– SiO2and CaO · Al2O3– SiO2at 1600°C.
ISSN:0003-8962
DOI:10.1002/srin.199101296
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
Thermodynamic conditions for inclusions modification in calcium treated steel |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 289-295
Vasilij Prešern,
Blaženko Koroušić,
John W. Hastie,
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摘要:
The presented paper discussed the fundamental or common thermodynamical relations between calcium‐treated aluminium‐killed molten steel and non‐metallic inclusions. The phase and chemical analyses of inclusions have proven that the correctness of calcium addition can be confirmed and that the analysis of those phenomena can show the effects of previous calcium treatment of aluminium‐killed steel. To make the process of manufacturing quality steel successful the factor affecting the necessary calcium addition should be taken into consideration already during the process. Steel, containing too much calcium could have CaS inclusions with a high melting point, while too low contents of calcium cause unsatisfactory modification of solid alumina inclusions to complex liquid calcium‐aluminate inclusions. This research included the examination of thermodynamic relations in calcium addition and its reactions with solid Al2O3inclusions. A detailed analysis of the CaO–Al2O3binary system established the modification of solid alumina inclusions via the following intermediate phases: CaO · 6Al2O3, CaO · 2Al2O3, CaO · Al2O3and liquid phase 12CaO · 7Al2O3and finally again solid CaO, at 1873 K (1600°C). The investigation discusses the further research engaged in consideration of CaO‐ and Al2O3‐activities change in each of the quoted intermediate phases. The system as a whole includes details of oxygen activities.
ISSN:0003-8962
DOI:10.1002/srin.199101297
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
ECSC announcements |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 295-295
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ISSN:0003-8962
DOI:10.1002/srin.199101298
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Mass transfer of dissolved gas from a liquid into a rising bubble swarm |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 296-302
Stefan Schneider,
Yongkun Xie,
Franz Oeters,
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摘要:
Mass transfer of dissolved gas from a liquid into a rising bubble swarm of inert gas is a transitoric reaction. The theory of such processes is described. The extraction of carbon dioxide dissolved in water by air purging was measured as a model reaction. It was found that the overall rate constant of the reaction is almost exclusively determined by the purging‐gas blowing‐rate. Nozzle position and number of nozzles have no influence on the reaction rate. This finding is explained by the fact, observed elsewhere, that the bubble size distribution function is constant and only a function of the liquid's physical properties. The measured rate constants agree with theoretically calculated ones, if the influence of turbulence on mass transfer into the bubbles is considered.
ISSN:0003-8962
DOI:10.1002/srin.199101299
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
Einfluß der Metall‐ und Schlackengehalte sowie der Temperatur auf die Entphosphorung mit kalkgesättigten Frischschlacken bei 1600 und 1700°C |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 303-313
Eberhard Schürmann,
Heribert Fischer,
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摘要:
Um niedrigste Phosphorgehalte im Stahl während des Frischprozesses einstellen zu können, ist die genaue Kenntnis der Einflüsse auf das Gleichgewicht zwischen Metall und Schlacke erforderlich. Daher wurde in Laborversuchen die gemeinsame Mangan‐und Phosphoroxidation aus Eisenschmelzen durch im Kalktiegel gesättigte, komplexe Frischschlacken bei 1600 und 1700°C untersucht. Die Mangangehalte des Metallbades wurden zwischen 0 und 0,36 % variiert. Zunächst werden die Eisen‐ und die Manganreaktionen durchleuchtet. Die Auswertung der Ergebnisse zeigt eine ausgeprägte Neigung zur Entmischung entlang der Kalksättigung. Die Phosphorgehalte des Metallbades sind bei niedrigen Phosphorgehalten der Schlacke eine lineare Funktion der (PO3‐4)‐Gehalte. Neben dem Einfluß der Eisengehalte der Schlacke und der Temperatur spielt die Wirkung des Bad‐Mangans für die Werte der Phosphorverteilung zwischen Schlacke und Metall eine wichtige Rolle. Die Kennzahlen der Reaktionen werden als Funktion der Temperatur, der Eisengehalte der Schlacke und der Mangangehalte angegeben.
ISSN:0003-8962
DOI:10.1002/srin.199101300
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
Effects of tribologically‐penetrated hydrogen on the abrasive wear of mild steel in H2SO4solution |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 314-319
Su‐Il Pyun,
Jong‐Sang Kim,
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摘要:
The present work examines how tribologically‐penetrated hydrogen affects the abrasive wear of mild steel in H2SO4solution. The pin‐on‐disc type wear tests were carried out as a function of applied load at 298 K in 0.5 M H2SO4aqueous solution in the presence and absence of 10−4As2O3mol I−1as a hydrogen recombination poison with and without concurrent hydrogen‐charging into the mild‐steel pin specimen. Hydrogen‐charging was electrolytically made for 4 h as a function of current density of 0.5 to 100 mA cm−2. Subsequently, hydrogen‐extraction measurements were performed from the worn pin specimen by using electrochemical hydrogen permeation technique, in order to determine the amount of hydrogen tribologically‐penetrated into the pin specimen. The increased amount of the penetrated hydrogen by abrading action indicated tribologically‐enhanced hydrogen penetration. The amount of penetrated hydrogen increased with charging current density or by addition of hydrogen recombination poison. As the current density increased, the corrosive‐wear rate decreased and then increased, regardless of applied load or addition of hydrogen recombination poison. This indicated that a critical amount of the penetrated hydrogen exists, which is necessary for transition to cracking and dominates the mechanism in abrasive wear. Two‐staged variation of the corrosive‐wear rate with respect to the amount of penetrated hydrogen is discussed in terms of ploughing/cutting to cutting/cracking transition in the mechanism of abrasive wear.
ISSN:0003-8962
DOI:10.1002/srin.199101301
出版商:Wiley
年代:2016
数据来源: WILEY
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8. |
ECSC announcements |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 319-319
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ISSN:0003-8962
DOI:10.1002/srin.199101302
出版商:Wiley
年代:2016
数据来源: WILEY
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9. |
Fatigue crack propagation in weathering weldable steel KT 315 Si |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 320-324
Annegret Benke,
Stefan Schädlich,
Gustav Zouhar,
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摘要:
Complex loading conditions are typical for structural materials, especially for steels. Fatigue crack propagation measurements during bend loading were carried out with different load ratios on a newly developed weathering steel KT 315 Si. This steel indicates an improved corrosion resistance in comparison with the weathering steel KT 315. Scanning electron microscopy of the fracture surfaces and quantitative microstructure analysis by means of light microscopy were applied to elucidate relations between microstructure and mechanical properties. An important result of the investigation is that the steel KT 315 Si reveals a lowered mean stress sensitivity of the fatigue threshold value ΔKthin comparison with that of other ferritic‐pearlitic steels of the same strength level.
ISSN:0003-8962
DOI:10.1002/srin.199101303
出版商:Wiley
年代:2016
数据来源: WILEY
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10. |
Versagensverhalten langzeitbeanspruchter Zeitstandproben aus Schweißverbindungen warmfester Kraftwerksbaustähle |
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Archiv für das Eisenhüttenwesen,
Volume 62,
Issue 7,
2016,
Page 325-330
Karl Maile,
Heinrich Theofel,
Wilhelm Eckert,
Dorothe Schroeder‐Obst,
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摘要:
Langzeitbeanspruchte, gebrochene Zeitstandproben, die in Querrichtung aus Schweißverbindungen entnommen waren, wurden metallografisch untersucht. Es handelte sich dabei vorwiegend um artgleiche bzw. nicht artgleiche Schweißverbindungen von CrMo‐ und CrMoV‐legierten Stählen. Schwerpunkt der metallografischen Auswertung war die Ermittlung der Bruchlage und des Schädigungsmechanismus. Im Langzeitbereich, der in der Regel mit einem deutlichen Rückgang der Verformungsfähigkeit verbunden ist, konnte in fast allen Fällen der äußere, d. h. feinkörnige Bereich der Wärmeeinflußzone als Ort maximaler Kriechschädigung bzw. als Versagensstelle ermittelt werden. Bei hohen Beanspruchungen kann sich die Bruchlage in andere Bereiche der WEZ bzw. in den Grundwerkstoff oder das Schweißgut verlagern. Im Vergleich zur Zeitstandfestigkeit des Grundwerkstoffs ergeben sich bei Schweißverbindungen Werkstoff‐, temperatur‐ und belastungsspezifische Reduzierungen der Zeitstandfestigkeit.
ISSN:0003-8962
DOI:10.1002/srin.199101304
出版商:Wiley
年代:2016
数据来源: WILEY
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