1. |
Sensors based on new oxide electrolyte and oxygen reference materials for on‐line measurements in steel melts |
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Archiv für das Eisenhüttenwesen,
Volume 65,
Issue 5,
2016,
Page 167-172
Axel Weyl,
Shi Wei Tu,
Dieter Janke,
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摘要:
Oxygen sensors are helpful tools to control and monitor continuous operations in steelmaking processes, e.g. in ladle refining and in the tundish of a continuous casting system. Up to the present no suitable oxygen probes for on‐line measurements have been developed. In search of new sensors much work has been done to investigate and discuss possible error sources which impede the use of the conventional one‐reading probes for continuous measurements. In the present study modified plug‐type sensors and new combined tube plug‐type sensors with optimized cell design are presented. Furthermore, new solid oxide electrolytes combined with new reference materials are used to reduce the flux of ionic oxygen across the solid electrolyte and thereby minimize polarisation effects over extended periods. It is shown that these oxygen sensors enable reliable long‐term measurements over periods of at least 5 h in Al‐deoxidized unalloyed and high alloyed steel melts.
ISSN:0003-8962
DOI:10.1002/srin.199400947
出版商:Wiley
年代:2016
数据来源: WILEY
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2. |
Influence of thermomechanical treatment on the modification of austenite structure |
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Archiv für das Eisenhüttenwesen,
Volume 65,
Issue 5,
2016,
Page 173-177
Christian Biegus,
Ulrich Lotter,
Radko Kaspar,
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摘要:
As a substantial subject of the work reviewing the effect of thermomechanical treatment (TMT) on the γ/&‐transformation of steel, this paper gives a survey of the metallurgical processes in the austenite as a consequence of hot deformation. These processes determine the properties of the austenite structure from which the transformation takes place. The dynamic and static recrystallization which refine the coarse grain formed during reheating are treated. For the case that at most minimal recrystallization occurs, the deformation structures arising from hot deformation are described under the aspect of their roll as nucleation sites for the γ/&‐transformation.
ISSN:0003-8962
DOI:10.1002/srin.199400948
出版商:Wiley
年代:2016
数据来源: WILEY
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3. |
On the structure and properties of high‐nitrogen low‐carbon non‐austenitic steels |
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Archiv für das Eisenhüttenwesen,
Volume 65,
Issue 5,
2016,
Page 178-183
Oleg Alexandrovich Bannykh,
Victor Michailovich Blinov,
Vladimir Borisovich Proscurin,
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摘要:
Phase transformations, when cooling and heating non‐austenitic high‐nitrogen low‐carbon steels containing chromium and other alloying elements, as well as structure and mechanical properties of these steels were analyzed. It was confirmed that these steels have high temperature chromium diffusion controlled pearlitic type transformation and martensitic type transformation. Experimental high nitrogen steels after quenching and tempering provide mechanical properties of about the same level as high strength commercial alloyed steels. Features of nitrogen as an alloying element in steels discussed allow the supposition of a possible reduction of the consumption of nickel, manganese, molybdenum or tungsten in high strength alloyed steels.
ISSN:0003-8962
DOI:10.1002/srin.199400949
出版商:Wiley
年代:2016
数据来源: WILEY
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4. |
Creep‐rupture strength of a martensitic chromium steel after annealing between 750 and 950 °C |
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Archiv für das Eisenhüttenwesen,
Volume 65,
Issue 5,
2016,
Page 184-186
Ludwig Schäfer,
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摘要:
The influence of various temperature transients on the tirne‐to‐rupture of a martensitic chromium steel was investigated in tests in which the transient temperature and transient time, cooling rate, and test temperature were varied systematically. Above a temperature of approximately 800 °C an austenitic structure is produced which can be transformed back into martensite by rapid cooling to a temperature below approximately 200 °C. The time‐to‐rupture of this martensite may be reduced by a factor of five compared to the initial condition. At annealing temperatures below 780 °C (Ac1b) this loss in time‐to‐rupture is either less pronounced or non‐existent. If austenite produced above some 800 °C is cooled slowly, pearlite of very low creep‐rupture strength is generated, or the austenite remains in existence above 300 °C and, depending on the test temperature, also may have an unsatisfactory creep‐rupture strength.
ISSN:0003-8962
DOI:10.1002/srin.199400950
出版商:Wiley
年代:2016
数据来源: WILEY
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5. |
Evaluation of the influence of welding on creep resistance |
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Archiv für das Eisenhüttenwesen,
Volume 65,
Issue 5,
2016,
Page 187-196
Cornelis F. Etienne,
Jan H. Heerings,
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摘要:
An evaluation is presented of the influence of welding on the uniaxial creep rupture behaviour of some ferritic, martensitic and austenitic creep resistant materials. After a description of evaluation the most reliable figures for the effect of welding will be presented in the form of two parameters. One is the strength reduction factor (SRF) for design conditions. The other is the lifetime reduction factor (LRF) for judging the lifetime of welded components at normal design stresses. Two criteria will be introduced to judge whether the introduction of a stress reduction factor for design of welded components is advisable. The needs for further research in this field are indicated.
ISSN:0003-8962
DOI:10.1002/srin.199400951
出版商:Wiley
年代:2016
数据来源: WILEY
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6. |
Microstructure behaviour of steel 15 CrMoV 5 10 under creep conditions |
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Archiv für das Eisenhüttenwesen,
Volume 65,
Issue 5,
2016,
Page 197-201
Peter Lenk,
Anne Schulze,
Katrin Pieszek,
Bernd Melzer,
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摘要:
Investigations of the influence of heat treatment (cooling rate from austenitizing temperature, tempering conditions) on the mechanical properties at room temperature as well as the structural parameters, which influence the creep resistant properties ‐ bainite content, type, quantity, size and distribution of carbides, alloying content of the matrix ‐ were made on the heat resistant pipe steel 15 CrMoV 5 10. The structures, produced by optimized heat treatment conditions, are characterized by a high bainite content as well as finely dispersed VCN‐ and Mo2C‐precipitates and small grain boundary carbides. During the creep process more Mo2C‐carbides precipitate above all at the dislocations inhibiting their motion. This process is accelerated by creep deformation and essentially contributes to the long‐term creep resistance of the steel 15 CrMoV 5 10.
ISSN:0003-8962
DOI:10.1002/srin.199400952
出版商:Wiley
年代:2016
数据来源: WILEY
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7. |
Microstructures and mechanical properties of intermetallic NiAl‐Cr alloys |
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Archiv für das Eisenhüttenwesen,
Volume 65,
Issue 5,
2016,
Page 202-211
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PDF (1081KB)
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ISSN:0003-8962
DOI:10.1002/srin.199400953
出版商:Wiley
年代:2016
数据来源: WILEY
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