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. 72 (1986), No. 14

  • Development of High Purity CO Gas Recovery System for BOF Gas by Modified PSA Process

    pp. 1813-1817

    Bookmark

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

    Log in / Sign Up
  • Development of "Car-ceramics"

    pp. 1818-1822

    Bookmark

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

    Log in / Sign Up
  • On-line Analysis Studies within the European Community for Steel and Coal

    pp. 1823-1842

    Bookmark

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

    Log in / Sign Up
  • 鉄鋼科学・技術史委員会教育ワーキング・グループ報告

    pp. 1843-1846

    Bookmark

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

    Log in / Sign Up
  • Analysis of Combustion Zone in Raceway under Operation of Pulverized Coal Injection

    pp. 1847-1854

    Bookmark

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

    Log in / Sign Up
    A theoretical reaction model of combustion zone in the raceway has been developed on the basis of the reaction engineering by taking account of movement, volatilization and combustion of pulverized coal inthe blow pipe and the tuyere. Furthermore the effects of some PCI(Pulverized Coal Ingection) parameters on the distribution of process variables in the combustion zone are examined.
    Volatilization and combustion of pulverized coal in the blowpipe zone considerably affect combustion reactions in the raceway region. The PCI operation not only shifts the distribution patterns of temperature and composition of gas in the raceway toward the tuyere nose, but also decreases the maximum temperature in the raceway. Such effects become particularly remarkable with the increase in injection rate ofpulverized coal. At the operation with constant theoretical flame temperature, however, only the distribution of process variables is varied toward the tuyere nose while the temperature level is maintained. Theincreases of blast temperature and pressure also shift the distribution of process variables toward tuyerenose, and these effects are gradually saturated at Tb>l473 and P>0.26 MPa.
  • Application of High Temperature Properties Test Results to Blast Furnace Operation Analysis and Quality Design of Sinter

    pp. 1855-1861

    Bookmark

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

    Log in / Sign Up
    Heating-up reduction tests under load were carried out for investigating high temperature propertiesby using various kinds of sinter made by sintering pot. On the basis of test results, it was clarified that high temperature properties of sinter could be primarily evaluated by its cold strength and reduction properties at low temperatures. The close relation between high temperature properties of sinter and blast furnace performance was confirmed from the operation analysis of actual blast furnace.
    Moreover, quality design of sinter for blast furnace operation is described. The direction of improvement of sinter quality was discussed.
  • Lubrication Phenomena in a Mold and Optimum Mold Oscillation Mode in High-speed Casting

    pp. 1862-1869

    Bookmark

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

    Log in / Sign Up
    High speed casting of slabs has become one of the mandatory requirements for improvement of productivity and energy conservation of continuous casting processes. In high-speed casting, however, the lubrication ability of powder between the mold and the solidified shell is deteriorated by increasingcasting velocity, and the shell sticking in the mold results in breakout. In order to increase the casting speed, therefore, one of the most important factors is to improve lubrication in the mold.
    First, we have carried out quantitative analyses on lubrication phenomena between mold and solidified shell and casting tests with an experimental continuous caster to make in-depth studies on the lubricationmechanism in the mold. Second, based on the results, we have proposed the new concept of mold oscillation for high speed casting.
    The results are summarized as follows:
    1) Liquid lubrication is dominant at the portion of closely below the meniscus than solid lubrication, and solid lubrication is dominant in the lower portion of the mould.
    2) Non-sinusoidal oscillation mode is more effective to reduce the friction force between mold and shell than the conventional sinusoidal one.
    By the application of the results of these fundamental studies, Fukuyama No. 5 continuous slab caster has been operating at a maximum casting speed of 2.5 m/min without occurrence of breakout, using anon-sinusoidal oscillation mode and powder with a low melting point and low viscosity.
  • Mathematical Models of Roll Force and Torque in Steel Bar Rolling

    pp. 1870-1876

    Bookmark

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

    Log in / Sign Up
    This paper describes a new method for calculating roll force and torque in Square_??_Oval, Round_??_Oval, Square_??_Diamond, Oval→Oval, and Diamond→Diamond passes. We conducted hot steel bar rolling experiments, and investigated some characteristics related with roll force and torque. The shape of projected contact area can be approximated as follows; in the Square→Oval pass, it is approximated by concave rectangular; in the Round_??_Oval, Oval→Oval and Oval→Square passes, by half ellipse; in the Square_??_Diamond and Diamond→Diamond passes, by cosine curves. The mean deformation resistance can be calculated by an equivalent rectangular transformation method. The non-dimensional roll force and torque arm coefficient are expressed as simple functions of a common roll gap ratio.
  • Spread Characteristics and Spread Formula in Steel Bar Rolling

    pp. 1877-1880

    Bookmark

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

    Log in / Sign Up
    This paper describes the spread phenomena and geometrical models in Oval-Square, Oval-Round, Diamond-Square, Diamond-Diamond and Oval-Oval passes. The experiments have been conducted by caliber rolling of hot steel bars. The profile of stress-free surface differs for the five types of passes; in the Oval-Square, Oval-Oval and Oval-Round passes, it is approximated by circular arcs with the same radius of initial bars; in the Diamond-Diamond and Diamond-Square passes, its angle after rolling is slightly smaller than before rolling. A spread formula proposed by the authors previously has been proven to be fundamentally available to all of these five passes.
  • Continuous Heat Treatment from Hot Forging on the Machining of Bearing Steel in Supercooled Austenitic State

    pp. 1881-1888

    Bookmark

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

    Log in / Sign Up
    A new machining process, called auscutting, has been developed in which the cutting operation is per-formed in supercooled austenitic state during quenching. In this paper, the optimum heat cycle condition which saves much thermal energy and time in the continuous process for manufacturing bearing races from hot forging to auscutting is investigated from the viewpoint of the quenched structure. Furthermore, under the obtained optimum heat cycle condition, the machinability and the rolling fatigue life are investigated.
    The results obtained are summarized as follows:
    (1) The optimum heat cycle process with auscutting is (hot forging)→(air cooling to 650°C)→(slow heating to 850°C and soaking)→(quenching to 200°C)→(auscutting)→(air cooling). Thermal energy in this process with auscutting is about 36% less than that in the conventional process.
    (2) Under the optimum heat cycle, the machinability in auscutting is not worse than that under theconventional heat cycle and the rolling fatigue life is about 3-4 times longer than that under the conven-tional heat cycle.
  • Epoxy-coated Bars for Concrete Construction

    pp. 1889-1896

    Bookmark

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

    Log in / Sign Up
    Epoxy-coated bars have been developed to prevent the deterioration of concrete structures due to reinforcement corrosion. The properties of corrosion resistance, bendability without serious damages of coating, bond strength to concrete, resistivity to percussion and abrasion are required for the bars. To examine the bars, exposure test in marine environments, bend test, pull-out from concrete and trial execution were carried out.
    (1)Epoxy-coated bars did not corrode in crack-induced concrete specimens which were exposed in marineenvironments for 3 years. (2) Epoxy-coated bars could be bent 180° with the radius of twice the diameter of the bars under the ordinary conditions of execution. (3) The reduction of the bond strength of epoxycoated bars to concrete required 20% increase of lap joint lengths. (4) The bars embeded in concrete beams which were subjected repeated bending stress up to 38 kgf/mm2 showed no degradation of coatings. (5) Cares for coating protection did not reduce the work efficiency of bending and construction of the bars in execution yard.
  • Corrosion Resistance of Painted Zinc Plated Steel in Sodium Chloride Solution

    pp. 1897-1904

    Bookmark

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

    Log in / Sign Up
    A series of immersion tests were carried out by using coupled samples to accelerate deterioration of painted specimens in 5%NaCl solution. Coupled samples consisted of two electrically conected pieces aselectrodes. One was a painted specimen and the other was unpainted. The time dependence of galvanic current on coupled samples coresponded to the accumulation of alkali in the underfilm solution of paintedspecimens. Adhesion strength correlated to the amount of galvanic current. The corrosion resistance of painted specimens(Rt) in 5%NaCl can be calculated from the frequency response of AC-impedance measurements. The effects of chemical conversion coating against underfilm corrosion were also analyzed by electrochemical techniques.
  • Effect of Surface Pre-treatments on the Durability of Composite Light-weight Steel Sheets

    pp. 1905-1912

    Bookmark

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

    Log in / Sign Up
    For light-weight steel sheets which consist of skin steels and thermoplastic resin, strong adhesion between skin steels and resin is required to get excellent qualities. To improve durability of the adhesion-strength, various surface pre-treatments were examined. Experimental results showed that pre-treatment for skin steels was effective to get the good adhesion-durability. Chromate treatment showed the most suitable effect and when the coating weight of Cr is 40 mg/m2, the light-weight steel sheet has the highest adhesion strength and corrosion resistance. This excellent durability is considered to be due to the strong and stable bonding between polarized base of PP resin and hydrized Cr-oxide on the surface of chromate layer. Silane-coupling-agent and organic resin are effective for improving initial adhesionstrength between steel and resin, however they are inferior to chromate treatment on the durability, especially on the corrosion resistance.
  • Effect of Mo and C on Toughness of 1/2 Mo Steel for Pressure Vessel

    pp. 1913-1920

    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 C contents on the impact properties of 1/2Mo steels utilized in the pressure vessel of the petroleum refining equipments, were investigated to improve the toughness.
    (1) Molibdenum addition suppresses the formation of ferrite in the steel resulting in the improvement in the toughness. On the other hand, if the microstructure of the specimens is constituted by the same volume fraction of ferrite, pearlite, and bainite, increasing Mo content decreases the upper shelf energy andincreases the vTrs.
    (2) Increasing C content from 0.15 to 0.30% in 1/2Mo steels lowers the toughness.
    (3) On the basis of the experimental results on the relation between vTrs and microstructure of steels with 0.15-0.75%Mo, it is found that good toughness is obtained and the variation of which was very small if steel plates had more than 40% bainite in volume. The above condition was realized by the appropriate cooling rate according to the plate thickness.
  • Effect of Nitrogen and Carbon Equivalent on Properties of Powder Metallurgical W-Mo Series High-speed Steel

    pp. 1921-1928

    Bookmark

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

    Log in / Sign Up
    Four grades of JIS SKH 51 high speed steel having 0.9% and 1.3% carbon equivalent with and without carbon replacement by 0.5% nitrogen were produced by using gas atomized powders and HIP processing.The influence of nitrogen on properties of SKH 51 was investigated. The following results were obtainedin this study.
    (1) Incipient melting temperature is dependent only upon carbon content, but not upon nitrogencontent.
    (2) The curves of quench hardness versus austenitizing temperature have shifted to higher temperature significantly by the replacement of carbon by nitrogen.
    (3) The amountof retained austenite is closely related to carbon equivalent, but this value is slightly lower at the same carbon equivalent in the nitrogen-containing steels. From the results of chemic alanalysis of extracted residues (precipitates), EPMA and EDX analyses of MC and M6C, it is deduced that the above mentioned behavior is caused by the change in the concentration of constituent in the matrices and by the stabilization of precipitates resulted from the redistribution of alloying elements in MC and matrices.
  • Effect of Nitrogen and Carbon Equivalent on Properties of Powder Metallurgical W Series High V High-speed Steel

    pp. 1929-1936

    Bookmark

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

    Log in / Sign Up
    The effect of systematic variation in nitrogen and/or carbon content upon the properties of cutting tool materials were investigated for JIS SKH 10 series high-speed steels (0.6 to 1.5%C, 0 to 1.0%N, 4%Cr, 12%W, 5%V and 5%Co). These steels were produced by using gas atomized powders and HIP processing.
    The following results were obtained in this study.
    1) Effect of nitrogen on incipient melting temperature is greater than that of carbon. Compared with JIS SKH51 series, effect of nitrogen is larger and incipient melting temperature decreases about 4°C with increasing 0.1%N.
    2) Bend strength increases with replacement of carbon by nitrogen.
    3) From the result of Ohogoshi's wear test, improvement of adhesive wear resistance was found on the steel with more than 0.4%N.
  • Effects of Lowering Si and Impurites on Temper-embrittlement and Creep Rupture Strength in Cr-Mo-V Steel for Turbine Rotor

    pp. 1937-1943

    Bookmark

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

    Log in / Sign Up
    Effects of lowering Si and impurities on temper embrittlement and creep rupture strength in Cr-Mo-V steel were investigated, using specimens with various amounts of Si (0.020.26 wt%) and embrittlementfactor X (4.3-25.4).
    (1) Microstructure of samples with a heat treatment corresponding to the center position in a large rotor was completely bainitic without ferrite, even though with reducing Si content to 0.02 wt%.
    (2) Temper embrittlement susceptibility decreased with lowering Si content and X. Low Si low X steelwas not embrittled by the step-cooling treatment.
    (3) Creep rupture strength of low Si and low X steel remarkably increased beyond that of high Si and high X steel.
    (4) A low Si and low X turbine rotor of actual size (32t) was manufactured as a trial based on the above basic investigation, and it was proved that this had higher creep rupture strength than that of commercial one, and was not embrittled by aging at elevated temperature.
  • Drift of PR Thermocouples in Long-term Creep Testing

    pp. 1944-1951

    Bookmark

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

    Log in / Sign Up
    Using more than 1000 creep testing machines, an extensive creep testingprogram for National Research Institute for Metals(NRIM), Creep Data Sheets has been conducted at NRIM since 1967. In conducting suchtesting program at high temperature, an essential practice is to control the test temperature within the required tolerance throughout the test duration. About 3400 PR (Pt/Pt·Rh) thermocouples have been used in the long-term creep testing in the temperature range from 400 to 1000°C up to 100000h.
    The EMF (electromotive force) of PR thermocouples decreases with time at hight emperatures. Therefore, most of the thermocouples have been subjected to the calibration before and after the tests. Thus, accumulation has been made on the vast amounts of calibration data on the drift of EMF of PR thermocouples used in creep tests. This paper describes the practice on handling and the calibration of PR thermocouples at the Creep Testing Division of NRIM. Based on the numerous calibration data, anempirical equation to represent the maximum drifty Y(°C)with the temperature T(°C) and the time t(h)has been derived:
    Y=-12.8+1.79(logt)+6.75×10-2(logt)2+1.14×10-2T.
    This equation is available for l ≤Y≤5°C, 450 ≤T≤900°C, and t≤100000h.
  • Development of Long-term Creep-fatigue Testing Machines

    pp. 1952-1957

    Bookmark

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

    Log in / Sign Up
    Two types of long-term creep-fatigue testing system have been newly developed; onewith a cam-and-lever driven by a servo-electric motor, and the other with a heat-actuator where the temperature is controlled in a closed loop circuit. Characteristics of the systems are summarizedas follows:
    (1) Axial strain control is possible with in limited strain rate.
    (2) The mechanism is simple and compact.
    (3) Reliability is high and maintenance is easy.
    (4) The systems are suitable for the tests with long strain holds at high temperatures.
    (5) Simulation tests of actual thermal and strain histories for high temperature component are applicable.
  • Analysis of Colored Films on Ferritic and Austenitic Stainless Steels

    pp. 1958-1964

    Bookmark

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

    Log in / Sign Up
    The characteristics of colored films on Type 304, Type 430 and Type 329J1 stainless steel formed in a solution containing chromic and sulphuric acid at 80°C were studied.
    The composition and structure of each colored film were examined using Secondary Ion Mass Spectrometry (SIMS), Electron Spectroscopy for Chemical Analysis (ESCA) and Transmission Electron Microscope(TEM).
    An uniform and bright color film was formed on Type 304, however, a dark color was observed on Type 430 and Type 329Jl. It was found that the nature of films depends upon the corrosion resistance of each stainless steel against a treatment solution. A lot of pits were found in the grains on Type 430. On thecontrary little corrosion occurred in that on Type 304. Corrosion local cells brought about a preferential growth of films near grain boundary. The uneven thickness of colored film on ferritic stainless steels is thought to give rise to the optical dispersion and to decline reflectance. Therefore, a dark color is observed.
  • 溶融石英質耐火物のマンガン鋼による侵食/新素材と鉄鋼-競合か協調か?

    pp. 1965-1969

    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