Steel Science Portal

ISIJ International
New Arrival Alert : OFF

You can use this feature after you logged into the site.
Please click the button below.

Log in / Sign up

Grid List Abstracts

ONLINE ISSN: 1347-5460
PRINT ISSN: 0915-1559

ISIJ International Vol. 39 (1999), No. 3

  • Coanda Effect on Liquid Flow Characteristics in a Bubbling Jet Rising near the Side Wall of a Cylindrical Vessel

    Manabu Iguchi, Kiyoto Sasaki

    pp. 213-218

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.213

    Abstract

    An air-water bubbling jet rising near the side wall of a cylindrical vessel is known to be pulled towards the side wall through the Coanda effect. Once the bubbling jet attaches to the side wall, it rises along the side wall all the way. The mean velocity and turbulence components of water flow in the bubbling jet were measured with a two-channel laser Doppler velocimeter. In the vertical (axial) region located above the attachment position, the horizontal (radial) distributions of the axial mean velocity component u and the root-mean-square values of the axial and radial turbulence components, u'rms and v'rms, followed their respective similar distributions just like the horizontal distributions of bubble frequency and gas holdup. The maximum values of u and u'rms agreed favourably with those obtained in a vertical bubbling jet free from the Coanda effect, and hence, these values were not affected by the side wall. However, the maximum value of v'rms became smaller than that in the vertical bubbling jet because the horizontal turbulence motions were suppressed due to the confinement effect of the side wall.

  • The Rate of Nitrogen Desorption from Liquid Iron by Blowing Argon Gas under the Condition of Non-inductive Stirring

    Zhu Jun, Kusuhiro Mukai

    pp. 219-228

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.219

    Abstract

    The nitrogen desorption reaction by blowing argon gas onto the surface of liquid iron containing various oxygen contents has been studied in a resistance furnace. Using a periscopic high temperature lens the Marangoni convection was qualitatively observed in the process of nitrogen desorption. In terms of the experimental results and gas-liquid metal reaction kinetic theory, the procedure of the nitrogen desorption is discussed. The nitrogen desorption from liquid iron under the condition of non-inductive stirring exhibits a 1.5th order dependence with respect to the nitrogen concentration in the melt regardless of oxygen content. The rate of nitrogen desorption is controlled by three mixed rate-controlling steps of gas-and liquid-phase mass transfers and chemical reaction at the gas-metal interface and mainly by the latter two steps. It was deduced that the decrease of the nitrogen desorption rate which accompanies the increment of oxygen concentration was mainly attributed to the attenuation of Marangoni convection and the increase of chemical reaction resistance at the interface in the present study.

  • Co-injection of Noncoking Coal and Natural Gas in Blast Furnace

    A. Babich, S. Yaroshevskii, A. Formoso, A. Cores, L. Garcia, V. Nozdrachev

    pp. 229-238

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.229

    Abstract

    The most radical method for saving coke in ironmaking is to inject gaseous, liquid and solid substitutes into the blast furnace (BF) hearth by means of tuyeres. Use of one or another type of auxiliary fuel depends on the ratio of their prices, their deposits and the peculiarity of the technology.
    This paper presents the basic theoretical proposals of a technology for the simultaneous injection by tuyeres of natural gas (NG) and pulverized coal (PC) with any ratio up to complete exception of one of them. A laboratory study has been carried out of the thermal decomposition and gasification of different types of coals. Determination has been made of the softening temperature and melting temperature of the ash of these coals. These temperatures play an important role in optimizing the tuyere assembly design, raceway processes and slag regimes. The factors which determine the oxidizing potential of the raceway have been established.
    A study has been made of the comparative estimation of NG and PC and the compensation rates for BF operational conditions with simultaneous injection ranges of 0-100 m3/tHM NG and 0-200 kg/tHM PC, at a flame temperature of 1950-2150ºC and maintaining other blast and burden parameters constant. The rates automatically compensate the changes in temperature and the thermal and oxidizing potential in the raceway.
    This technology and tuyere assembly design are successfully used at two BFs.

    Recommended Articles: Influence of Coal Moisture Control on Carbon Deposition in the Coke Oven Chamber [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Influence of Coal Moisture Control on Carbon Deposition in the Coke Oven Chamber ISIJ International Vol.38(1998), No.12
    2. A Development of Computer Model for Simulating the Transport Phenomena in COREX Melter-gasifier ISIJ International Vol.39(1999), No.4
    3. Hydrogen Utilization for Carbon Recycling Iron Making System ISIJ International Vol.52(2012), No.8

  • Assimilation and Mineral Formation during Sintering for Blends Containing Magnetite Concentrate and Hematite/Pisolite Sintering Fines

    L. X. Yang, L. Davis

    pp. 239-245

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.239

    Abstract

    Blends for sintering in China commonly contain domestic magnetite concentrate and imported hematite or/and pisolite sintering fines. Interactions between these ores will, no doubt, have an important impact on sintering performance and sinter quality of these blends. Studies have been carried out to look at assimilation of sintering fines and mineral formation during sintering of such blends.
    The results show that at given mix composition, pisolite ores are easier to be assimilated than hematite and magnetite ores while magnetite shows the least assimilation. For the same ore, the assimilation depends on melt level and ore porosity. For this reason, higher assimilation was observed for porous ores or ores with high gangue content or when an easy-fusing ore was present in the blend.
    Studies on mineral phase formation of blends containing magnetite, hematite and pisolite indicate that good sinter mineralogy with increasing SFCA (silico-ferrite of calcium and aluminium) content is obtained with increasing Ore E (hematite). Substitution of Ore J (pisolite) for various hematite ores did not lead to significant changes in sinter mineralogy. The only change was the reduced level of primary hematite owing to the high reactivity of Ore J.

    Recommended Articles: Admixing Hydrocarbons in Raw Mix to Reduce NOx Emission in Iron Ore Sintering Process [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Admixing Hydrocarbons in Raw Mix to Reduce NOx Emission in Iron Ore Sintering Process ISIJ International Vol.37(1997), No.4
    2. Sintering Reactions of Magnetite Concentrates under Various Atmospheres ISIJ International Vol.37(1997), No.11
    3. Determination of Size of Representative Volume Element for Coke Using Homogenization Method Based on Digital Image of Actual Microstructure ISIJ International Vol.52(2012), No.7

  • Numerical Simulation of Isothermal Dendritic Growth by Phase-field Model

    Jae Sang Lee, Toshio Suzuki

    pp. 246-252

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.246

    Abstract

    The phase-field model is applied to simulate microstructural evolution during isothermal dendritic growth of the δ-phase in undercooled Fe-C liquid. The parameters of phase-field equation are determined by a thin interface limit condition. Realistic dendritic structures at various temperatures and compositions of the alloy can be obtained using the phase-field model with the thin interface limit condition. The calculated results show various solidification features consistent with our experience. The calculated tip radius, the velocity and the concentration at the interface are compared with the predicted values from the conventional dendritic growth theory using Ivantsov solution and marginal stability criterion.

    Recommended Articles: Simulation of the Estimation of the Maximum Inclusion Size from 2-Dimensional Observation Data on the Basis of the Extreme Value of Statistics [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Simulation of the Estimation of the Maximum Inclusion Size from 2-Dimensional Observation Data on the Basis of the Extreme Value of Statistics ISIJ International Vol.49(2009), No.7
    2. Apparent Morphologies of Coarse Plate Martensite ISIJ International Vol.44(2004), No.4
    3. Phase Relations in Ce–Al–Fe–S Based Grain Refiners for Steels ISIJ International Vol.49(2009), No.7

  • The Effect of Thermal History on the Hot Ductility of Microalloyed Steels

    A. M. El-Wazri, F. Hassani, S. Yue, E. Es-Sadiqi, L. E. Collins, K. Iqbal

    pp. 253-262

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.253

    Abstract

    Transverse cracks in continuous cast steels can form if the hot ductility of the cast steel at the unbending stage is poor. To measure hot ductility, tensile specimens are usually reheated to a high temperature (preferably to the melting point), cooled to the test temperature and then isothermally fractured. In this work, high temperature tensile testing was used to determine the hot ductility of a Nb-Ti and a Ti-B microalloyed steel. However, instead of cooling directly to the test temperature after melting, the specimens were subjected to thermal histories typical of a continuously cast billet surface, and then, at the unbending temperature, subjected to a tensile test to fracture. In other words, physical simulations of the continuous casting procedure were performed. The results were compared with those generated by conventional isothermal tensile testing.
    For the isothermal tests, both steels exhibited a temperature range of low ductility. However, the physical simulations did not reveal such hot ductility behaviour. For both steels, almost all the physical simulation variants led to hot ductility values lower than predicted by the isothermal tests at the corresponding tensile test temperature. For the Nb-Ti steel, it was revealed that there is a critical minimum temperature, attained by the specimen during the thermal history, below which the hot ductility, measured at the tensile test temperature, is much reduced. It is assumed that this critical minimum temperature leads to the formation of grain boundary ferrite, which probably enhances the rate of formation of Nb precipitates, decreasing the hot ductility in this way. However, for the Ti-B steel, the effect of thermal history could not be explained in such a straightforward manner.

    Recommended Articles: Effects of Cooling Rate on Growth Behavior of Austenite Phase during Peritectic Reaction in Iron-Carbon Binary Alloy [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Effects of Cooling Rate on Growth Behavior of Austenite Phase during Peritectic Reaction in Iron-Carbon Binary Alloy ISIJ International Vol.35(1995), No.12
    2. Simulation of Microstructure of As-cast Steels in Continuous Casting ISIJ International Vol.46(2006), No.6
    3. A Model Estimating the Slab Corner Transverse Cracking Susceptibility of Microalloyed Steel Based on Microstructure MATERIALS TRANSACTIONS Vol.57(2016), No.1

  • Experimental Study of Free Growth of Equiaxed NH4Cl Crystals Settling in Undercooled NH4Cl-H2O Melts

    Benoît Appolaire, Virginie Albert, Hervé Combeau, Gérard Lesoult

    pp. 263-270

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.263

    Abstract

    The present study deals with experiments carried out to assess the influence of the movement of equiaxed crystals on their growth kinetics. The principle of the experiments is based on the settling of crystals growing in melts of transparent alloy undercooled at constant temperature. Ammonium chloride-water mixtures have been chosen for their convenient properties. The experimental set-up is composed of a settling tube and a video-device which allowed us to record continuously the images of dendritic NH4Cl equiaxed crystals all along their fall. On these images two kinds of morphology have been observed of which the difference seems to be related to the spinning movements of the crystals. Furthermore time evolutions of the vertical position and apparent sizes of the crystals have been measured. A careful examination of these measurements was necessary because of the uncertainties of the undercooling and of the actual shapes and sizes of the crystals which are inherent in the set-up and in the procedure. Average growth velocities were determined so as to identify some general trends concerning the effect of the settling on the growth of the equiaxed crystals. Finally, a short comparison between these average growth velocities and the corresponding theoretical ones without any convection has shown a strong influence of the convection on the equiaxed growth kinetics.

  • Analysis of the Austenite Grain Size Distribution in Plain Carbon Steels

    A. K. Giumelli, M. Militzer, E. B. Hawbolt

    pp. 271-280

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.271

    Abstract

    The aim of this paper is to report methods for measuring the austenite grain size in plain carbon steels, including the estimation of the three dimensional grain size distribution. Prior austenite boundaries are revealed using a number of quenching and etching techniques. The grain size is measured by standard manual procedures and by the use of image analysis equipment. Results from these measurement methods are compared and systematic errors are identified. A correction is proposed to account for the systematic error in the measurement of the two dimensional grain size distribution by the use of image analysis. Methods for the estimation of the three dimensional grain size distribution are compared. It is concluded that the method proposed by Matsuura and Itoh is the most versatile.

    Recommended Articles: Evaluation of Transformation Latent Heat in C-Mn Steels [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Evaluation of Transformation Latent Heat in C-Mn Steels ISIJ International Vol.39(1999), No.3

  • Evaluation of Transformation Latent Heat in C-Mn Steels

    Jye-Long Lee, J. K. Chen, Y. T. Pan, K. C. Hsieh

    pp. 281-287

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.281

    Abstract

    Two sublattice thermodynamic model and DTA technique were adopted to determine the latent heat of α+Fe3C→γ transformation in C-Mn steels. The calculated latent heat varied with the transformation route. Supercooling resulted in higher latent heat than superheating. By splitting enthalpy change into components of specific heat and latent heat, the equilibrium latent heat was calculated and proven to be a constant independent of cooling or heating. The latent heat determined using DTA agreed very well with calculation as carbon content was higher than 0.45 wt%, while it was significantly lower than calculation at lower carbon content. The inconsistency was attributed to that lower carbon steels had a wide transformation temperature range, but DTA only detected heat change over part of the range. Molar fraction of pearlite, latent heat absorbed per unit temperature, and the temperature range of transformation were found to be the three main factors affecting latent heat. Carbon and manganese additions increased latent heat by increasing molar fraction of pearlite, while silicon addition increased latent heat by expanding temperature range of transformation.

    Recommended Articles: Modified Effective Specific Heat Method of Solidification Problems [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Modified Effective Specific Heat Method of Solidification Problems MATERIALS TRANSACTIONS Vol.47(2006), No.11
    2. Analysis of the Austenite Grain Size Distribution in Plain Carbon Steels ISIJ International Vol.39(1999), No.3
    3. Application of Square-wave Pulse Heat Method to Thermal Properties Measurement of CaO–SiO2–Al2O3 System Fluxes ISIJ International Vol.46(2006), No.3

  • Effect of Volume Fraction of Constituent Phases on the Stress-Strain Relationship of Dual Phase Steels

    Thomas Hüper, Shigeru Endo, Nobuyuki Ishikawa, Koichi Osawa

    pp. 288-294

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.288

    Abstract

    Ferrite-martensite and ferrite-bainite dual phase steels (DP-steels) were prepared by applying accelerated cooling (AcC) process on a linepipe steel. Their stress-strain relationships were predicted by micromechanics. In the predictions, the stress-strain relationships of the constituent phases whose chemistries were determined by microscopic examinations and some thermodynamic data were used. The effect of volume fraction of the constituent phases on the stress-strain relationships of the DP-steels was also examined. According to the applied model, a simple stress-strain curve can be divided into three stages. As a result of this investigation, work hardening takes place in stage II and at the beginning of stage III. Further, in stage II, the hardening rate is strongly dependent on the volume fraction of the harder phase. In stage III, the hardening rate for each DP-steel is smaller than that in stage II and is related to the difference in tensile strength between the harder and the softer phases.
    Furthermore the second investigation by means of FEM analysis was carried out in order to evaluate the influence of variation of the volume fraction of the harder phase on the stress-strain behavior of a DP-steel. Tensile tests showed that by increasing the amount of the harder phase (bainite) in the DP-steel, Lüders elongation disappears. According to the results obtained by the FEM calculations, the stress-strain behavior is related to the microstructure, such as volume fraction and shape of the grains in the DP-steel.

    Recommended Articles: Modelling of Eutectoid Transformation in Plain Carbon Steel [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Modelling of Eutectoid Transformation in Plain Carbon Steel ISIJ International Vol.34(1994), No.4
    2. Dynamic Transformation of Austenite to Ferrite in Low Carbon Steel ISIJ International Vol.34(1994), No.3
    3. Effects of Microstructure on Stretch-flange-formability of 980 MPa Grade Cold-rolled Ultra High Strength Steel Sheets ISIJ International Vol.44(2004), No.3

  • Application of a Direct Current Anodic Voltammetric Technique to a 55mass%Al-Zn Coated Steel Sheet before and after an Annealing Heat Treatment

    T. M. C. Nogueira, M. A. S. Cruz, P. R. Rios

    pp. 295-297

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.295

  • Thermal Release of Hydrogen from High Strength Steel Containing Retained Austenite

    Harushige Tsubakino, Hisashi Harada, Jiang Yin

    pp. 298-300

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.2355/isijinternational.39.298

  • © 1999 The Iron and Steel Institute of Japan

Article Access Ranking

03 Dec. (Last 30 Days)

  1. Structural and Mechanical Characterizations of Top Dross in a Molten Zinc Bath ISIJ International Advance Publication
  2. Perspective toward Long-term Global Goal for Carbon Dioxide Mitigation in Steel Industry Tetsu-to-Hagané Vol.105(2019), No.6
  3. Determination of Facet Plane and Cleavage Fracture Plane of the Top Dross Formed in a Molten Zinc Bath ISIJ International Advance Publication
  4. Effect of Hydrogen Concentration in Reducing Gas on the Changes in Mineral Phases during Reduction of Iron Ore Sinter ISIJ International Advance Publication
  5. Effect of Microstructure at Coating Layer on Fatigue Strength in Hot-Dip Galvanized Steel ISIJ International Vol.60(2020), No.11
  6. Identification of Cracking Issues and Process Improvements through Plant Monitoring and Numerical Modelling of Secondary Cooling during Continuous Casting of HSLA Steels ISIJ International Advance Publication
  7. Contributions of Grain Size and Crystal Orientation to Fatigue Crack Deflection and Branching Behavior in Low Carbon Steel Plates ISIJ International Advance Publication
  8. Crystal Structure Analysis of Top Dross in Molten Zinc Bath by First Principles Calculation and Synchrotron X-ray Diffraction ISIJ International Advance Publication
  9. Volumetric Strain Dependence of Quantum Diffusion of Hydrogen in bcc Iron ISIJ International Advance Publication
  10. Reaction Behaviors of Mixed Burdens Consisting of Pellets and Sintered Ores in an Experimental Blast Furnace ISIJ International Vol.60(2020), No.11

Search Phrase Ranking

03 Dec. (Last 30 Days)

  1. blast furnace
  2. blast furnace permeability
  3. blast furnace productivity
  4. steel
  5. bearing 52100 100cr6 rolling contact fatigue
  6. toshihiko emi
  7. toshihiro kitamura
  8. dwtt pressed notch
  9. electromagnetic stirring
  10. fatigue crack path prediction in udimet 720 nickel-based alloy single crystals