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. 48 (1962), No. 2

  • 日本鉄鋼協会の拡大強化について

    pp. 103-104

    Bookmark

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

    Log in / Sign Up
  • Studies on Contamination of Thermocouples Used for Continuous Temperature Measurement of Steel Bath

    pp. 105-111

    Bookmark

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

    Log in / Sign Up
    In the first report (Tetsu-to-Hagané, 47 (1961) 11, p.1982-1988), the authors described the continuous immersion pyrometry method of molten steel in ladle and some results thereof. In order to establish this method, it was neccessary to keep the degree of contamination of thermocouple elements as low as possible.
    To obtain high accuracy of actual measurement, the contamination of every thrmocouple wires used for each measurements is studied by the measurement of the drop of e. m. f., the examination of the distribution of parasitic e. m. f. and the spectrographic analysis etc. And, the tentative method to caluculate the error which was appearing during the actual measurement was considered. The main results obtained by these studies were as follows:
    (1) Value of parasitic e. m. f. on the PtRh element is positive. This seems to be the characteristic of the contamination for this case.
    (2) The error which is appearing during actual measurement can be caluculated by the next formula:
    ΔT=Σi {ΔT1 (EPt1-EPtRh1) /1000F1}
    (3) The degree of contamination of thermocouple elements depends on a temperature distribution along the wire, diameter of the wire, the insulating and protecting tube.
    (4) To attain to the lower degree of contamination on the thermocouple elements and the lower cost of measurement, it is better to use a wire of smaller diameter.
    (5) It is desirable to avoid the successive use of thermocouples for a high-accuracy measurement.
  • On Dissolution of Water Vapour in Molten Slags

    pp. 111-117

    Bookmark

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

    Log in / Sign Up
    The solubility of hydrogen in a synthetic and basic open hearth steelmaking slags of molten lime-silica-iron oxide system has been determined experimentally.
    The hydrogen absorption of these slags is rapid. After the beginning of reaction, the twothirds of the equilibrium hydrogen is absorbed within ten minutes, and only one hour is necessary to reach equilibrium. The solubility of hydrogen in slags is increased in proportion to the square root of the partial pressure of water vapour in the atmosphere with which slag stands in equilibrium, and also is increased with rising reaction temperature. The heat of solution of water vapour into slag is about 13kcal/mol.
    The effect of slag basicity on hydrogen solubility is remarkable. In the range CaO/SiO2 greater than unity, solubility is increased linearly with rising basicity. The solubility reaches the minimum when CaO/SiO2 is equal to unity, and in the range CaO/SiO2 less than unity, is increased again with falling CaO/SiO2. But, when slag contains much amount of iron oxide, the solubility does not increase in the range CaO/SiO2 less than unity.
    Comparing the experimental results of synthetic slag studies with results from industrial heats, a good coincidence has been obtained.
  • Deoxidation and Inclusions in Semi-Killed Steel Ingots

    pp. 117-123

    Bookmark

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

    Log in / Sign Up
    Numerous black spots are usually observed on sulphur prints along the skin layers of semi-killed steel ingots, which probably may develop into surface defects under severe processing of semi-killed steel products.
    Using 10 ton slab ingots, investigations were carried out into the effects of deoxidizers on these black spots.
    The main results obtained are as follows:
    (1) The substances of these black spots consist of crowds of sulphides to be accompanied with blow holes and of large silicates, the greater part of which contains some sulphides.
    (2) These black spots can be reduced by using aluminium as the main deoxidizer instead of silicon, although this result may be also attained by the decrease of sulphur content of molten steel.
    (3) The large silicates have mnch relations with ladle refractories. When silicon is used as deoxidizer, it can catch a greater amount of oxygen, as the temperature of molten steel drops during the period from tapping to solidifying, whereas in case aluminium is used, the content of residual aluminium in molten steel cannot be expected to be high because of its strong deoxidizing power to combine with more oxygen while cooling. It is presumed, therefore, that in order to get the same condition of blow holes in ingots, the oxygen content of molten steel in ladle should be lower, and accordingly the ladle refractories are the less damaged when aluminium is used as deoxidizer than when silicon is used.
  • On the Manufacture of High-Chromium Steels in High-Pressure Nitrogen Atmosphere and the Heat-Resisting Properties of Type 316 L Steels

    pp. 123-133

    Bookmark

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

    Log in / Sign Up
    An experimental study was made on the fundamental phenomena occuring in melting and casting of various high-chromium steels in high-pressure nitrogen atmosphere and on the influence of nitrogen content on heat-resisting properties of type 316L steels. It was confirmed that the solubility of nitrogen in the type 316L steel melted at about 1550°C in nitrogen atmosphere up to 10 atm obeys the Sieverts' law, and was represented by the following equation:
    %N=0.183 (PN2) 1/2
    The high-pressure melting was also c1arried out for such steels as 10-25%Cr-20%Ni-Fe alloys, 17-4PH type stainless steels containing 0.5% or 3% of Si, 18%Cr-4%Ni stainless steels, 18%Cr-8%Mn stainless steels, 22%Cr stainless steels containing O or 2% of Ni and LCN-155 alloys, and the effects on ingot soundness of nitrogen contents, melting conditions, casting conditions and of the sort of the phase formed in process of solidification, were discussed in detail. Further, it was confirmed that the nitrogen contained in these ingots did not diffuse out from the steel unless it was heated to high temperatures in high vacuum.
    It was observed also that the nitrogen raised the strength of type 316L steels at both room and high-temperatures, the ductility at high temperatures dropped considerably and high temperature creep-rupture strength of the steels showed the maximum at a nitrogen content of about 0.33%.
    x

    Readers Who Read This Article Also Read

    1. 製鋼・転炉 Tetsu-to-Hagané Vol.47(1961), No.3
    2. Continuous Annealing of Cold-Rolled Sheets Tetsu-to-Hagané Vol.49(1963), No.1
    3. 日本鉄鋼協会第60回講演大会講演大要 Tetsu-to-Hagané Vol.46(1960), No.10
  • Metallurgical Investigation into Ancient Iron Wares

    pp. 134-142

    Bookmark

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

    Log in / Sign Up
    After having carried out the “Metallurgical Investigation into Ancient Iron Nails” (Tetsuto-Hagané 48 (1962), No. 1, pp. 44-49), the authors have made metallurgical investigation successively into the ancient iron wares such as clamps, rivets, ornamental fittings used in “Hôôdo” (main hall) of “Byôdô-in” temple, three-storied pagoda of “Meitsûji” temple and five-storied pagoda of “Daigo-ji” temple. Results obtained are summarized as follows.
    (1) Manufacturing process,
    Chemical compositions, nonmetallic inclusions and hardness are almost the same as those of the ancient nails, excepting two or three specimens made in a later period which have shown high P content.
    (2) As to the cast iron product, the C content is somewhat higher and the P is somewhat less than cast iron used at present. The Si, Mn and S are noticeably low.
    (3) Correlation of the quality of specimens and the age of their manufacture could not be grasped clearly, because there were a considerable dispersion of data between specimens manufactured in the same age. Nevertheless it seemed reliable that the older the manufactured age, the higher the purity is.
  • Effects of Alloying Elements on Temperability and Mechanical Properties of Low-Alloy Structural Steel (SNCM8)

    pp. 143-148

    Bookmark

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

    Log in / Sign Up
    In the previous paper (Tetsu-to-Hagané vol. 48, (1961), 1, pp. 34-38) effect of increasing of Ni, Cr, Mo and V, and decreasing of C content to the hardenability of Ni-Cr-Mo steel (SNCM 8: SAE 4340) was reported.
    In this paper, by using the same test materials and the same quench-cooling rate, as those in the, previous paper, the mechanical properties in as-tempered condition were examined in connection with their alloying elements. The test specimens quenched at 4 different cooling rates were tempered at appropriate temperature so as to obtain as-tempered strength of 80 to 130kg /mm2. Then a comprehensive study was made on temper-softening tendency, tensil property and notched impact property at room temperature (20°C) and -40°C. A study on sensitivity of temper-embrittlement was also performed.
  • Effects of Solution Treatment on High-Temperature Properties of 18Cr-8Ni-Ti Steel

    pp. 148-155

    Bookmark

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

    Log in / Sign Up
    The present study was carried out to make clear the effects of solution treatment on the creep rupture properties of type 321 stainless steel.
    To prepare test pieces, three kinds of stainless steel bars, 17Cr-9Ni, 17Cr-9Ni-Ti and 18 Cr-11Ni-Ti with 25mm diameter were reduced to 15mm diameter by “hot-cold working” at 500°C after water-cooling from 1050°C. And then these specimens were solution-treated at various temperatures between 800°C and 1200°C for 1 hour. Some of these were reheated at 1000°C for 2 hours, 900°C for 5 hours and 800°C for 100 hours after water-cooling from 1100°C.
    The obtained results were summarized as follows.
    (1) Low-temperature heat-treated material had very fine grains and a low rupture strength. However, with increase of solution temperature it showed coarser grains and a higher strength. but a decreased rupture elongation. In general, rupture elongation of 18Cr-8Ni steel was larger than that of 18Cr-8Ni-Ti steel.
    The effect of solution-treating temperature on the creep rupture strength of 18Cr-8Ni-Ti steel was very larger than that of 18Cr-8Ni steel.
    (2) With the 18Cr-8Ni-Ti steel which had been water-cooled or furnace-cooled from 1100°C, reheated at 1000°C and 900°C after solution treatment at 1100°C, there was a considerable difference among their carbide precipitation in microstructure, although there was little difference among their creep rupture strength. Specimens which had been reheated at 800°C for 100 hours after water-cooling from 1100°C, showed a lower creep rupture strength than that of water-cooled specimens.
    (3) It is presumed that the variation of strength with solution-treating temperature and time was related to both grain size and solubility of carbide.
  • Applications of Internal Friction to Studies of Iron and Steels

    pp. 156-176

    Bookmark

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

    Log in / Sign Up
  • 抄録

    pp. 177-182

    Bookmark

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

    Log in / Sign Up
  • 鉄鋼ニューズ

    pp. 185-186

    Bookmark

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

    Log in / Sign Up

Article Access Ranking

08 Dec. (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. Effect of Interfacial Properties on Agglomeration of Inclusions in Molten Steels ISIJ International Vol.59(2019), No.10
  3. Corrosion Behavior of Alumina Containing Refractory in Blast Furnace Hearth by CaO–SiO2–MgO–Al2O3–Cr2O3 Slags ISIJ International Vol.59(2019), No.11
  4. Numerical Simulation on Influence of Coke Oven Gas Injection on Iron Ore Sintering ISIJ International Advance Publication
  5. Nanostructured Bainitic Bearing Steel ISIJ International Advance Publication
  6. Analysis of the Coke Particle Size Distribution and Porosity of Deadman Based on Blast Furnace Hearth Dissection ISIJ International Vol.59(2019), No.11
  7. State of the Art in the Control of Inclusions in Spring Steel for Automobile - a Review ISIJ International Advance Publication
  8. Mathematical Modelling Study of Dynamic Composition Change of Steel and Mold Flux in Continuous Casting of Steel ISIJ International Vol.59(2019), No.11
  9. Formation Mechanism of Coarse Austenite Grain during Hot Forging and Cooling in Case Hardening Steel Tetsu-to-Hagané Advance Publication
  10. Morphology Change and Carburization Characteristic of Iron Ore-Coal Composite During Reduction under a Simulated Condition of Blast Furnace ISIJ International Vol.59(2019), No.11

Search Phrase Ranking

08 Dec. (Last 30 Days)

  1. blast furnace
  2. blast furnace permeability
  3. blast furnace productivity
  4. cohesive zone
  5. steel
  6. pellet
  7. hot rolling
  8. basicity
  9. mold
  10. argon bubbles