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
ONLINE ISSN: 1883-2954
PRINT ISSN: 0021-1575

Tetsu-to-Hagané Vol. 75 (1989), No. 10

  • Present and Future Trends in Moving Bed Operation

    pp. 1815-1823

    Bookmark

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

    Log in / Sign Up
  • Preparation and Certification of Blast Furnace Slag for Japanese Iron and Steel

    pp. 1824-1828

    Bookmark

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

    Log in / Sign Up
  • Progress of Filtration Technologies for Inclusion Removal

    pp. 1829-1838

    Bookmark

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

    Log in / Sign Up
  • Strength Degradation of Heat Resisting Alloys in High Temperature Corrosive Environments

    pp. 1839-1851

    Bookmark

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

    Log in / Sign Up
  • Corrosion of Materials in Molten Carbonate Fuel Cell

    pp. 1852-1860

    Bookmark

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

    Log in / Sign Up
  • The Effect of Size of Non-coking Coal Added on Coke Degradation

    pp. 1861-1868

    Bookmark

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

    Log in / Sign Up
    The mechanism of coke degradation by solution-loss reaction in the blast furnace was experimentally studied, and a resistance index for coke degradation under blast furnace conditions was established. The effects of coke texture and structure on coke degradation were also studied in order to allow the use of larger amounts of high-volatile non-coking coal.
    When the concentration of CO2 gas diffusing into lump coke was decreased, the degradation of the entire lump of coke was limited and coke wear decreased. This would be realized if coke with high reactivity and low porosity could be produced, as far as the pore walls had the permissible strength. This suggests that high-volatile non-coking coal with a highly reactive coke structure can be used.
    We also showed that the degradation resistance index under blast furnace conditions could be increased by controlling the dispersion of the texture derived from the non-coking coal, considering its preferential reaction. Thus, we obtained a guide for coke production with non-coking coal.
  • Reduction Behavior of Chromium Ore Pellet Mixed with Coke Powder in the Heating Process

    pp. 1869-1876

    Bookmark

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

    Log in / Sign Up
    To clarify the reduction process of chromium ore the pellet of chromium ore fines mixed with coke powder was heated in a coke powder bed at various reaction temperatures, such as 1200, 1300, 1400 and 1 500°C.
    The metalized fractions of Fe and Cr were evaluated by chemical analyses, and the variations of microstructure and composition of pellet in the reduction process were measured by using microscope, X-ray diffraction and EPMA. The following results were obtained.
    The reduction curves of the pellets showed that the reduction rate of iron oxides and chromium oxides depends mainly on temperature. EPMA analysis showed that the firstly reduced Fe diffuses from the inside of ore particle to both its surface and the crack in it and then condenses with redution, and the lately reduced Cr diffuses into the Fe grains and is intergrated mutually.
  • Measurement of Thermal Diffusivity of Fired and Nonfired Pellets by Laser Flash Method

    pp. 1877-1882

    Bookmark

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

    Log in / Sign Up
    The nonfired pellets have received attention in ironmaking industries from the point of view of energy saving. However, the accurate and systematic measurements of thermal diffusivity of nonfired pellets have not been reported yet, although they are required for the heat transfer analysis of ironmaking process. For these requirements, thermal diffuisivities of three kinds of nonfired pellets containing 1.20, 3.72 and 8.43 mass% combined water have been determined by the laser flash method in the temperature range between room temperature and 1273 K, and were compared with that of a fired pellet.
    Thermal diffusivity values of the nonfired pellets are found smaller than that of the fired pellet, and significantly depend on temperature and kinds of iron ore as raw material.
    Laser flash method for measuring thermal diffusivity at high temperature has been successfully applied to various materials for its excellent character such as high response and non-contact method.
  • Dissolution and Reduction Behaviors of Chromite Ore in Molten Slag

    pp. 1883-1890

    Bookmark

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

    Log in / Sign Up
    Experiments have been done on the smelting reduction of powdered chromite ore by graphite in the molten slag of CaO-MgO-Al2O3-SiO2 system at the temperatures between 1 550 and 1 650°C.
    The dissolution of chromite grains in slag proceeded usually from the grain surface and the surface became progressively enriched in MgO and Al2O3. However, the slag having the composition far remote from liquidus line penetrated into the inside of chromite grain and promoted the dissolution. The reduction took place mainly at the surface of graphite grain and proceeded more rapidly in the slag with higher concentration of SiO2and with lower concentration of MgO. Temperature dependence of the reduction rate decreased with the increase of temperature, because of change in the rate-determining step of smelting reduction with temperature. Besides, the chromium and iron contents of slag and the oxidation state of chromium in slag were examined.
  • Diffusivity of Ca45 in Molten FeO-CaO-SiO2 Slag Equilibrated with Solid Iron

    pp. 1891-1896

    Bookmark

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

    Log in / Sign Up
    The self- and mutual-diffusivity of Ca45 in FeO-SiO2-CaO and FeO-SiO2 melts equilibrated with solid iron have been measured in the temperature range 1 270 to 1 450°C using the capillary reservoir method with Ca45 as the radioactive tracer. The results obtained are represented by Ds = (2.54 ± 0.50) exp (- 39 700 ± 10 000/RT) (cm2/s) for the self-diffusivity of Ca45 in FeO 60 mass%-SiO2 33 mass%CaO 7 mass% melt and, Dm= (190 ± 10) exp (- 52 500 ± 10 000/RT) (cm2/s) for the mutual-diffusivity of Ca45 in FeO 68 mass%-SiO2 32 mass% melt.
  • Development of Separation and Evaluation Technique of Non-metallic Inclusions in steel by Electron Beam Melting

    pp. 1897-1904

    Bookmark

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

    Log in / Sign Up
    In order to evaluate amount, size, shape and composition of Non-Metallic Inclusions (NMI) in metal quickly with high accuracy, an Electron Beam (EB) method was developed.
    During melting of metal sample by EB, NMI floats on the top surface of the button-shape metal. Suitable irradiation energy which does not change the original form of NMI was made clear. The results by the present EB method were compared with those by conventional evaluation methods of NMI in metals, and this method was found equivalent to microscopic and oxygen analysis methods.
    This method was applied to commercial grade steels, and it was found that the EB method was effective for various estimations in steel manufacturing, for example, for studying the effect of decrease of NMI during continuous casting, various phenomena by determining the size, shape and composition of NMI, and quality of ultra high purity metals. Especially, this method was of benefit to aluminum-killed steels.
  • Three-dimensional Elasto-plastic and Creep Analysis of Bulging in Continuously Cast Slabs

    pp. 1905-1912

    Bookmark

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

    Log in / Sign Up
    The bulging behavior of the solidified shell in continuously cast slabs have been numerically analyzed using the elasto-plastic and creep Finite Element Method. Three-dimensional model has been applied in order to investigate the effect of the narrow face shell on restraining the bulging deflection. Three-dimensional shell profile and temperature distribution in it have been determined using a mathematical model of solidification which takes account of solute segregation. In this way, strains occurring at the solidification front near the narrow face of the slab, as well as those occurring in the broad face have been computed. The computed bulging deflection have been in good agreement with measurements, and the relationship between the strain caused by the bulging and the internal cracks have been investigated. In addition, the effect of the slab width on the bulging are discussed.
  • Production of Ti-6Al-4V Alloy Powders by Plasma Rotating Electrode Process

    pp. 1913-1920

    Bookmark

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

    Log in / Sign Up
    The experimental study of the production of Ti-6Al-4V powders by the rotating electrode process ( PREP) was carried out in order to determine the optimum operating conditions to obtain the powders consisting of uniform particle size. The average particle size of the powders decreases by increasing the diameter of rotating electrodes (anodes made of Ti-6Al-4V), and their rotating speed. Under the condition of the anode diameter of 30 mm and the rotating velocity of 200 s-1, on average diameter of the powder particles of 270 μm with a minimum standard deviation of 10μm was attained by controlling plasma gas flow, plasma current and melting rate of the anode to be 1.7 X 10 -5m -3·S -1, 200 A and 1.53.0 X 10-7 M3· s-1, respectively. In order to keep such a small standard deviation of the particle size of the powder, it was also important to maintain a homogeneous melting condition on the anode surface.
  • Effects of Mo and V on High Temperature Properties of Precipitation Hardening Type 15Cr-26Ni-1.25Mo Alloy

    pp. 1921-1927

    Bookmark

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

    Log in / Sign Up
    Effects of Mo and V contents on high temperature properties, such as creep rupture strength and aging embrittlement, had been investigated in precipitation strengthened type 15Cr-26Ni-1.25Mo alloy. Of test materials, Mo and V content were varied from 1.03 to 2.00 wt%, and from 0.01 to 0.39wt% respectively.
    The results obtained are summerized as follows.
    1) Both Mo and V did not remarkably affect the tensile properties at 20°C in the above mentioned range of contents.
    2) The highest creep rupture strengths were obtained at 650 and 700°C, when the Mo content was 2.00 wt%. The more marked effect of Mo on creep rupture strength was observed, as the exposure time and temperature increased.
    3) After aging at 650°C for 6 000 h, the Charpy absorbed energy was decreased with increasing Mo content. In addition, the morphology of the fracture changed from the transgranular fracture to the intergranular one in the alloy with higher Mo content.
    4) The aging embrittlement at 650°C seems to be caused by grain boundary precipitates, which mainly consist of χ phase (Mo5Cr6Fe18) in the higher Mo added alloys.
  • Low Cycle Fatigue Behaviour of Pressure Vessel Steels in High Temperature Pressurized Water

    pp. 1928-1935

    Bookmark

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

    Log in / Sign Up
    Low cycle fatigue behaviour of low alloy steels JIS SFVQ1A (equivalent to ASTM A508 cl. 3) and SQV2A (A533B cl. 1) for reactor pressure vessel was investigated in high temperature pressurized water environment. Total strain range, strain rate and dissolved oxygen (DO) concentration were varied from 0.5% to 2.2%, 0.1%/s to 0.001%/s and 10 ppb to 8 000 ppb, respectively. Fatigue tests in ambient air and 561K air were also conducted for comparison.
    Reduction of fatigue life in high temperature water environment was observed. It decreased with decreasing total strain range and rather longer fatigue lives than those in air were observed at lower total strain range. SQV2A steel showed a distinct strain rate dependence of fatigue life compared to SFVQ1A steel, while both steels showed a similar DO concentration dependence. It was found that fatigue cracks initiated at surface corrosion pits due to MnS inclusion and the low cycle fatigue behaviour of both steels depended on their sulphur contents.
    It can be conclusively remarked that the materials tested possess a plenty of safety margin in high temperature water environment by judging from the fact that the present data fell on the points far above the design fatigue curve in the ASME Code Sec.III.
  • Determination and Precipitation Behavior of σ-phase, Carbides and Nitrides in Duplex Stainless Steels

    pp. 1936-1942

    Bookmark

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

    Log in / Sign Up
    A method for quantitative analysis of σ-phase, carbides and nitrides in duplex stainless steel was investigated and the analytical procedure has been established. And then, precipitation behavior of the σ-phase in duplex stainless steel was investigated by using this method.
    The results obtained are summarized as follows :
    (1) The residues adhered to the sample surface after potentiostatic electrolysis in 1%HCl-10% acetylacetone-methanol electrolyte (1%HA) can not be teared off by only ultrasonic cleaning, and in this case, the residues can be teared off by polishing the sample surface with a wire brush.
    (2) Only the σ-phase in the above mentioned precipitates is gradually dissolved by 10%Br2-methanol dissolution treatment, and consequently the composition of the σ-phase can be analyzed by using this solution.
    (3) The precipitates except the σ-phase are quantitatively extracted by galvanostatic electrolysis in 10% tetramethyl ammoniumchloride-10% acetylacetone-methanol electrolyte (10%TMAC), and the amount and composition of carbides and nitrides can be analyzed.
    (4) The amount and composition of the σ-phase, carbides and nitrides can be analyzed by using the procedures from (1) to (3) and previous report.
    (5) The formation of the σ-phase is very fast at 1 073 K, and the amount of the σ-phase is quite larger than that of carbides and nitrides.
  • Application of Scanning Tunneling Microscope to Metal Fatigue

    pp. 1943-1946

    Bookmark

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

    Log in / Sign Up
  • アレキサンドリアでの仕事と生活(アレキサンドリア滞在記-1)

    pp. 1947-1950

    Bookmark

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

    Log in / Sign Up
  • アメリカの工学系大学院博士課程終了者数の大学順位(1987~1988)

    pp. 1956-1956

    Bookmark

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

    Log in / Sign Up

Article Access Ranking

25 Mar. (Last 30 Days)

  1. Dependence of Carbon Concentration and Alloying Elements on the Stability of Iron Carbides ISIJ International Advance Publication
  2. Comprehensive Optimization Control Technology of Rolling Energy and Oil Consumption in Double Cold Rolling ISIJ International Advance Publication
  3. Experiments on Removal of Hydrophilic Fine Particles in Bubbly Flow ISIJ International Vol.59(2019), No.2
  4. Effects of Impurities and Processing Conditions in Al–1%Mn Alloys on the Formation of Thermally Stabilized Substructures MATERIALS TRANSACTIONS Vol.59(2018), No.11
  5. Temperature Field Distribution of a Dissected Blast Furnace ISIJ International Advance Publication
  6. Coating Film Profiles Generated by Fluctuating Location of the Wiping Pressure and Shear Stress ISIJ International Vol.59(2019), No.2
  7. Effect of EAF Slag Temperature and Composition on its Electrical Conductivity ISIJ International Vol.59(2019), No.2
  8. Fundamentals of Silico-Ferrite of Calcium and Aluminium (SFCA) Iron Ore Sinter Bonding Phase Formation: Effects of Basicity and Magnesium on Crystallisation during Cooling ISIJ International Vol.59(2019), No.2
  9. Evolution of Blast Furnace Process toward Reductant Flexibility and Carbon Dioxide Mitigation in Steel Works ISIJ International Vol.56(2016), No.10
  10. Structure Based Viscosity Model for Aluminosilicate Slag ISIJ International Advance Publication

Search Phrase Ranking

25 Mar. (Last 30 Days)

  1. blast furnace
  2. blast furnace productivity
  3. blast furnace permeability
  4. galvanizing
  5. tuyere abrasion
  6. tuyere erosion
  7. tuyere failure
  8. lme
  9. wear on tuyere
  10. 鉄と鋼