Steel Science Portal

Tetsu-to-Hagané
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: 1883-2954
PRINT ISSN: 0021-1575

Tetsu-to-Hagané Vol. 102 (2016), No. 4

  • Interaction between Alumina Inclusions in Molten Steel Due to Cavity Bridge Force

    Katsuhiro Sasai

    pp. 187-195

    Bookmark

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

    Log in / Sign Up

    DOI:10.2355/tetsutohagane.TETSU-2015-072

    Abstract

    The formation and extinction behavior of cavity bridges has been experimentally evaluated by allowing the cylindrical particles simulating inclusions to approach and separate off in mercury and in molten steel. An interaction model of spherical alumina particles close to the actual inclusion shape due to cavity bridge force has been developed on the basis of the experimental results. Using this interaction model, the processes of agglomeration and separation of alumina inclusions in molten steel have been analyzed, and the agglomeration force due to cavity bridge force has been discussed in comparison with different agglomeration forces that are derived from the van der Waals force in molten steel and the capillary force on the surface of molten steel. When two isospherical alumina inclusions are approaching each other in molten steel, a large agglomeration force of 1.54 d·σFe (d: the diameter of alumina inclusions, σFe: the surface tension of molten steel.) is generated by the cavity bridge formation from the interparticle surface distance of 0.07 d, and then the agglomeration force also gradually increases to reach the maximum value of 1.88 d·σFe in complete contact state. Conversely, when two isospherical alumina inclusions in molten steel are separated from the contact state, a large agglomeration force of 0.92 d·σFe and above is maintained until the cavity bridge extinction in the interparticle surface distance of 0.12 d, whereas the agglomeration force gradually decrease from 1.88 d·σFe. In addition, it is assumed that alumina inclusions in aluminum deoxidized molten steel principally agglomerate and coalesce on the basis of the agglomeration force derived from very strong cavity bridge force in comparison with the van der Waals force in molten steel and the capillary force on the surface of molten steel, and coarse alumina clusters are thus formed in molten steel.

    Recommended Articles: Solid/liquid Mixing Pattern and its Comparison with Liquid/liquid One in a Mechanically- stirred Vessel [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Solid/liquid Mixing Pattern and its Comparison with Liquid/liquid One in a Mechanically- stirred Vessel Tetsu-to-Hagané Vol.102(2016), No.4
    2. Mechanism of Formation of Streak-shaped Defects on Ultra-low Carbon IF Steel for Automobile Outer Panels after Press Forming and Influence of Slab Reheating Temperature before Hot Rolling and Sb-addition on Defects Tetsu-to-Hagané Vol.102(2016), No.4
    3. Development of Analytical Methods for Free-MgO in Steelmaking Slag Tetsu-to-Hagané Vol.102(2016), No.1

  • Solid/liquid Mixing Pattern and its Comparison with Liquid/liquid One in a Mechanically- stirred Vessel

    Ryutaro Shiba, Md. Azhar Uddin, Yoshiei Kato

    pp. 196-201

    Bookmark

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

    Log in / Sign Up

    DOI:10.2355/tetsutohagane.TETSU-2015-100

    Abstract

    Solid/liquid mixing pattern was investigated and compared with the liquid/liquid one in a mechanically-stirred vessel. The cold model experiment was carried out to make clear the effect of operating factors such as volumetric ratio of solid particles to liquid, rotation speed, impeller position, etc. on the mixing pattern. The solid/liquid mixing pattern was observed visually and the vortex depth of solid/liquid or gas/liquid interface was measured with a ruler. It was categorized into 3 types as well as the liquid/liquid mixing pattern. I: the region where solid particles have no dispersion, II: the region where some of the solid particles disperse into liquid, III: the region where almost all of the solid particles disperse into liquid. The solid/liquid mixing pattern transits from I to II, and from II to III as the impeller depth decreased and the rotation speed increased. The transition of I-II shifted to a higher rotation speed in cases of smaller volumetric ratio of solid to liquid, larger particles diameter, larger density difference between solid-liquid and smaller liquid viscosity. The transition of II-III shifted to the higher rotation speed in cases of smaller impeller diameter and larger liquid viscosity, and showed independency on volumetric ratio of solid to liquid, particles diameter and density difference between solid and liquid. Multi regression analysis on the transition of I-II showed that the calculation agreed with the measurement. Dimensionless correlation equation on the transition of II-III also showed a good agreement between calculation and measurement and it was adaptable to liquid/liquid system.

    Recommended Articles: Influence of Gas Injection Pipe on CO2 Decomposition by CaCl2-CaO Molten Salt and ZrO2 Solid Electrolysis [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Influence of Gas Injection Pipe on CO2 Decomposition by CaCl2-CaO Molten Salt and ZrO2 Solid Electrolysis Tetsu-to-Hagané Vol.102(2016), No.4
    2. Interaction between Alumina Inclusions in Molten Steel Due to Cavity Bridge Force Tetsu-to-Hagané Vol.102(2016), No.4
    3. Effect of Slag Composition on Phosphorus Separation from Steelmaking Slag by Reduction Tetsu-to-Hagané Vol.102(2016), No.9

  • Mechanism of Formation of Streak-shaped Defects on Ultra-low Carbon IF Steel for Automobile Outer Panels after Press Forming and Influence of Slab Reheating Temperature before Hot Rolling and Sb-addition on Defects

    Hiroshi Tsunekawa, Takako Yamashita, Tomohiro Aoyama, Reiko Sugihara

    pp. 202-208

    Bookmark

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

    Log in / Sign Up

    DOI:10.2355/tetsutohagane.TETSU-2015-061

    Abstract

    Streak-shaped defects were infrequently observed on ultra-low carbon IF cold-rolled steel sheets for automotive outer panels after press-forming. The defects occurred due to heterogeneous remaining of elongated grains on the steel surface layer. Elongated grains are hard to recrystallize due to the pinning effect of small precipitates on grain boundaries. These precipitates consist mainly of Ti(NC), TiS and AlN. In order to eliminate the streak defect, lower excess Ti, lower temperature slab reheating and Sb-addition to the steel are efficient. These countermeasures result in a drastic reduction of the defect ratio. This improvement is considered to be obtained due to the reduction of small precipitates of Ti(CN), TiS and AlN in the steel surface layer.

    Recommended Articles: Interaction between Alumina Inclusions in Molten Steel Due to Cavity Bridge Force [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Interaction between Alumina Inclusions in Molten Steel Due to Cavity Bridge Force Tetsu-to-Hagané Vol.102(2016), No.4
    2. Quantification of Large Deformation with Punching in Dual Phase Steel and Change of its’ Microstructure – Part III: Micro-tensile Behavior of Pre-strained Dual-phase Steel Tetsu-to-Hagané Vol.102(2016), No.5
    3. Solid/liquid Mixing Pattern and its Comparison with Liquid/liquid One in a Mechanically- stirred Vessel Tetsu-to-Hagané Vol.102(2016), No.4

  • Effects of Nitrided Surface Layer and Microstructure on Press Formability in Commercially Pure Titanium Sheet Annealed in Nitrogen Gas Atmosphere

    Kazuhiro Takahashi, Teruhiko Hayashi, Kohsaku Ushioda

    pp. 209-218

    Bookmark

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

    Log in / Sign Up

    DOI:10.2355/tetsutohagane.TETSU-2015-079

    Abstract

    The effects of nitride layer and microstructure on the Erichsen value of commercially pure titanium JIS-class1 sheets were evaluated after cold rolling followed by annealing at 700~860°C both in nitrogen gas and in vacuum in order to clarify the controlling factors independently.
    Irrespective of the annealing methods, grain size increased with the increase in the annealing temperature; however, after the maximum grain size by annealing at 810°C, grain size decreased with the increase in the temperature, due to the retardation effect of grain growth by the presence of the β phase. The Erichsen value was confirmed to increase with the increase in grain size; however, even if grain size is the same, the titanium sheets annealed in the two phase (α+β) region exhibit inferior forming properties such as the Erichsen value, elongation and n-value than those annealed in the single α phase. The hard Fe rich region formed along α grain boundaries, which is originated from β to α phase transformation during cooling, is considered to impair the forming properties.
    Furthermore, the Erichsen value was evidently improved by annealing in nitrogen gas due to the formation of the nitride layer, which contributes to lowering the friction coefficient. However, the thick nitride layer formed at temperatures higher than 840°C no longer has the beneficial effect, because the thick nitride layer tends to easily fracture leading to fine cracks in the sheet surface. Annealing the sheets in the temperature range of 810~830°C for 30 s in nitrogen gas was the optimum condition for the best press formability.

    Recommended Articles: Recrystallization Behavior of Cu Containing Ferritic Stainless Steel Sheet [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Recrystallization Behavior of Cu Containing Ferritic Stainless Steel Sheet Tetsu-to-Hagané Vol.102(2016), No.2
    2. Fast and Continuous Analysis Method of Steel Pickling Solution Using Near-infrared Spectroscopy Tetsu-to-Hagané Vol.102(2016), No.2
    3. Capture Characteristics of Gaseous Elemental Mercury by Carbonized Waste in Air and Reducing Atmospheres Tetsu-to-Hagané Vol.102(2016), No.1

  • Influence of Gas Injection Pipe on CO2 Decomposition by CaCl2-CaO Molten Salt and ZrO2 Solid Electrolysis

    Sumito Ozawa, Hidetoshi Matsuno, Akio Fujibayashi, Takuya Uchiyama, Takafumi Wakamatsu, Norihito Sakaguchi, Ryosuke O. Suzuki

    pp. 219-225

    Bookmark

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

    Log in / Sign Up

    DOI:10.2355/tetsutohagane.TETSU-2015-025

    Abstract

    The electrochemical decomposition of carbon dioxide to form carbon and oxygen gas was studied in CaCl2-CaO molten salt. The water model experiment was carried out to study on the influence of the tip shape of the pipe, the pipe diameter and wettability to the gas injection pipe for the bubble shape in molten salt. Bubbles were formed in both conditions of horizontal and oblique tip with good wettability of the gas injection pipe. The specific surface area of bubble using oblique tip of the pipe was smaller than horizontal tip. On the other hand, slug flows appeared with poor wettability. In the hot mode experiment, the current density was measured, and the carbon dioxide gas concentration decreased. The carbons were detected from the sample after the experiment. The decrease of carbon dioxide gas concentration using oblique tip were more remarkable than the case using horizontal tip with the same pipe. It is likely that the form of carbon dioxide gases in the molten salt were bubbles shape.

    Recommended Articles: Solid/liquid Mixing Pattern and its Comparison with Liquid/liquid One in a Mechanically- stirred Vessel [ View more ]

    x

    Readers Who Read This Article Also Read

    1. Solid/liquid Mixing Pattern and its Comparison with Liquid/liquid One in a Mechanically- stirred Vessel Tetsu-to-Hagané Vol.102(2016), No.4
    2. Estimation of Lubrication and Heat Transfer by Measurement of Friction Force in Mold Tetsu-to-Hagané Vol.102(2016), No.10
    3. Fast and Continuous Analysis Method of Steel Pickling Solution Using Near-infrared Spectroscopy Tetsu-to-Hagané Vol.102(2016), No.2
  • © 2016 The Iron and Steel Institute of Japan

Article Access Ranking

02 Jun. (Last 30 Days)

  1. Perspective toward Long-term Global Goal for Carbon Dioxide Mitigation in Steel Industry Tetsu-to-Hagané Vol.105(2019), No.6
  2. Development of a Binder Manufacturing Process for Molded Coal Utilizing Used Plastics Tetsu-to-Hagané Vol.106(2020), No.5
  3. Influence of Understanding of Physical Phenomena in Materials on Supply Chain Patterns of Steel Products ISIJ International Advance Publication
  4. Microstructure and Mechanical Properties of Simulated Heat Affected Zone of Laser Welded Medium-Mn Steel ISIJ International Advance Publication
  5. State of the Art in the Control of Inclusions in Spring Steel for Automobile - a Review ISIJ International Vol.60(2020), No.4
  6. Analysis of Microstructures and Voids on Ductile Fracture of Ferrite/Martensite Dual-Phase Steels through Three-dimensional Observation Tetsu-to-Hagané Vol.106(2020), No.5
  7. Hydrogen-assisted Crack Propagation in Pre-strained Twinning-induced Plasticity Steel: from Initiation at a Small Defect to Failure ISIJ International Advance Publication
  8. A Review of the Twin-roll Casting Process for Complex Section Products ISIJ International Advance Publication
  9. Effect of Cooling Rate on the Controlled Solidification of “Fe2O3”–CaO–SiO2 Liquids in Air in Synthetic Iron Ore Sinter ISIJ International Vol.60(2020), No.5
  10. Improvement in Reduction Behavior of Sintered Ores in a Blast Furnace through Injection of Reformed Coke Oven Gas ISIJ International Advance Publication

Search Phrase Ranking

02 Jun. (Last 30 Days)

  1. blast furnace
  2. blast furnace productivity
  3. blast furnace permeability
  4. ferrosilicon
  5. hot blast stove
  6. stainless steel
  7. flame front speed sinter
  8. bearing steel
  9. blast furnace taphole
  10. cryogenic