1. |
Modelling of air ingress and pressure distribution in ladle shroud system for continuous casting of steel |
|
Archiv für das Eisenhüttenwesen,
Volume 66,
Issue 7,
2016,
Page 279-286
Laihua Wang,
Hae‐Geon Lee,
Peter Hayes,
Preview
|
PDF (808KB)
|
|
摘要:
The pressure distribution and fluid flow profiles whithin the slide gate and shroud nozzle for the continuous casting of steel have been investigated using a full scale water model and a CFD (computational fluid dynamics) model. The water modelling has shown that a large quantity of air can be drawn into the liquid stream if there is any breakdown of the seals in the vicinity of the slide gate. The 3‐dimensional numerical solution for highly turbulent flow has predicted the pressure distribution and velocity profile within the slide gate and shroud. Based on the experimental and numerical modelling, it has been shown that cavitation can occur near the slide gate during ladle teeming. This can be a source for erosion of the refractories. Improvements to the design of the ladle shroud system are recommended.
ISSN:0003-8962
DOI:10.1002/srin.199501125
出版商:Wiley
年代:2016
数据来源: WILEY
|
2. |
Flow dynamics in thin slab caster moulds |
|
Archiv für das Eisenhüttenwesen,
Volume 66,
Issue 7,
2016,
Page 287-293
Thomas Honeyands,
Joe Herbertson,
Preview
|
PDF (652KB)
|
|
摘要:
This study investigated the dynamic fluid flow phenomena that occurred in water models of a thin slab caster mould. The flow of fluid caused significant surface waves and was observed to be strongly oscillatory. The magnitude and the period of oscillation of these waves represent potential quality constraints in thin slab casting. The oscillation mechanism is explained in terms of the dynamic balance/imbalance between the pressure gradient across the jet emerging from the SEN and the opposing momentum of the recirculating, entrained flow.
ISSN:0003-8962
DOI:10.1002/srin.199501126
出版商:Wiley
年代:2016
数据来源: WILEY
|
3. |
Study of fluid flow in tundishes due to different types of inlet streams |
|
Archiv für das Eisenhüttenwesen,
Volume 66,
Issue 7,
2016,
Page 294-300
Sarbjit Singh,
Satish C. Koria,
Preview
|
PDF (674KB)
|
|
摘要:
Flow pattern and residence time distribution induced by different methods of pouring of molten steel into a tundish are studied by means of a water model with and without flow modifiers (FM). It was found that the submerged stream without FMs produces short circuiting and argon shrouded stream leads to excessive surface directed flow of liquid in a tundish. Open stream pouring generates surface turbulence and does not produce short circuiting. The effect of FM is found to be different for different methods of pouring, e.g. dam eliminates short circuiting and produces surface directed flow for submerged stream, whereas weir limits the surface turbulence within the inlet region for open stream pouring. Dam is found to reduce the dead volume for argon shrouded pouring.
ISSN:0003-8962
DOI:10.1002/srin.199501127
出版商:Wiley
年代:2016
数据来源: WILEY
|
4. |
An analysis of casting‐rolling force of viscous fluid and its technological influence |
|
Archiv für das Eisenhüttenwesen,
Volume 66,
Issue 7,
2016,
Page 301-304
Sun Binyu,
Zhang Hong,
Shi Rong,
Shen Baocheng,
Tong Yuquan,
Preview
|
PDF (304KB)
|
|
摘要:
In casting‐rolling process the velocity is very slow and, therefore, the deformed body is still in the state of liquid‐solid viscous flow. The rheological properties of the deformed body are described by the theory of mature hydromechanics. A velocity field was set by the flow function. The pressure field and velocity field of metal flow were combined, based on Navier‐Stokes equation. The distributional formula of the unit pressure in the deformed zone was obtained, and the calculation formulae for mean unit pressure in the casting‐rolling zone were established. In this paper, the influence of absolute draft, radius of casting‐rolling roll and front tension stress on the mean unit pressure had been discussed. Comparison of theoretical data with experimentally obtained values showed good agreement, thus proving the correctness of the theoretical formulae.
ISSN:0003-8962
DOI:10.1002/srin.199501128
出版商:Wiley
年代:2016
数据来源: WILEY
|
5. |
Structure forming processes during hot deformation of a C‐Mn‐V‐N steel |
|
Archiv für das Eisenhüttenwesen,
Volume 66,
Issue 7,
2016,
Page 305-308
Jan Adamczyk,
Manuel Carsi,
Roman Kozik,
Roman Wusatowski,
Preview
|
PDF (619KB)
|
|
摘要:
Medium carbon V‐N treated steel grade applied for long products and small drop forged parts investigated in a state of incomplete solution of V(C,N) precipitates. Activation energy changes investigated in the 850–1200°C temperature range and 0.6–30 s−1strain rate range is revealed to be temperature dependent. Calculated for σpflow stress value this energy in some cases expresses a combination of various processes. It is found that DRX starts well below ∊p. Softening during a short interpass time is caused by dynamic recrystallization DRX during forming and is followed by metadynamic recrystallization MDRX and static recrystallization SRX. At longer interpass times softening progress is hindered by precipitation.
ISSN:0003-8962
DOI:10.1002/srin.199501129
出版商:Wiley
年代:2016
数据来源: WILEY
|
6. |
Effect of thermomechanical treatment on structure and mechanical properties of Mo‐bearing dual phase steel |
|
Archiv für das Eisenhüttenwesen,
Volume 66,
Issue 7,
2016,
Page 309-317
Ashok Kumar Panda,
Ratan Indu Ganguly,
Dharba Subramanya Sarma,
Ramesh Chandra Gupta,
Somnath Misra,
Preview
|
PDF (1333KB)
|
|
摘要:
The effects of hot rolling of a dual phase steel in the (α + γ) range on microstructure and mechanical properties was investigated by using two thermomechanical (TMT) routes. The first consisted of heatingAc3, soaking, cooling to deformation temperature in the (α + γ) range. The second comprises heating to deformation temperature in the(α + γ) range, followed by rolling and quenching. Parameters varied were temperature (with the first route) and extent of deformation (with the second). The microstructures were characterised by optical and transmission electron microscopy. The results indicate a distinct difference in the final structure and properties due to the two different TMT routes. The first TMT route resulted in a greater amount of ferrite, finer lath width of martensite, finer ferrite grain size and increased density of dislocations. The strength properties decreased, the YS/UTS ratio decreased and ductility increased with the increase in the extent and temperature of deformation. However, TMT route 2 resulted in an increase in the amount of martensite, finer ferrite grain size, decrease in the martensite lath width and increased dislocation density. The strength properties increased, YS/UTS ratio increased and ductility decreased with increase in the extent and temperature of deformation.
ISSN:0003-8962
DOI:10.1002/srin.199501130
出版商:Wiley
年代:2016
数据来源: WILEY
|
7. |
Feasibility of fluidized bed CVD for the formation of protective coatings |
|
Archiv für das Eisenhüttenwesen,
Volume 66,
Issue 7,
2016,
Page 318-324
Stefan Kinkel,
George N. Angelopoulos,
Demetrios C. Papamantellos,
Winfried Dahl,
Preview
|
PDF (828KB)
|
|
摘要:
Attempts have been made to clarify the feasibility of a fluidized bed CVD (FBCVD) process as another method for the formation of cementing and diffusion coatings in order to improve wear, oxidation and corrosion resistance of metals.Treating agent powders consist of a donator, usually a powder of the metal, an alloy or a metal carbide or nitride of the coating forming metal, an activator, usually a halide or alkali metal halides, and a filler oxide, usually Al2O3, SiO2etc. The precursors of the coating forming metal are formed “in situ” the fluidized bed reactor by the reaction of the donator with the activator. The bed can be fluidized by inert or reactive gas or gas mixtures like Ar, N2, Ar + H2etc. As the parts can be charged and withdrawn while the furnace is at treating temperature, this process can be integrated into the heat treatment cycles.The FBCVD process was applied for the formation of Ti‐, V‐, Cr‐, Al‐, and Si‐bearing coatings. The produced coatings were dense and uniform over the whole specimen surface. According to the results, the use of the FBCVD process is promising since it can lead to a clean, flexible surface modification technology, combining adaptability with relatively low capital and operational costs.
ISSN:0003-8962
DOI:10.1002/srin.199501131
出版商:Wiley
年代:2016
数据来源: WILEY
|