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Toshiharu UCHIDA
1985 Volume 71 Issue 7 Pages
775-783
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Tsutomu NOZAKI, Seiji ITOYAMA
1985 Volume 71 Issue 7 Pages
784-793
Published: May 01, 1985
Released on J-STAGE: January 18, 2010
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Kazuo FUJIWARA
1985 Volume 71 Issue 7 Pages
794-799
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Mitsuo SATO
1985 Volume 71 Issue 7 Pages
800-806
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Hirohisa HOTTA, Yojiro YAMAOKA
1985 Volume 71 Issue 7 Pages
807-814
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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To evaluate high temperature properties of blast furnace burdens, a series of reduction under load tests were carried out under simulated blast furnace conditions, using sinter, self-fluxing pellets, and acid pellets. To investigate the softening and melting mechanism, structural analyses were conducted on those samples recovered after interrupting the test.
The results obtained are summarized as follows.
1) Formation of molten slag is involved in the assimilation of slag during softening and melting processes, and the basic path for this assimilation is considered to be toward the final composition (average slag composition before reduction) along the expanding direction of the low melting temperature range with heating.
2) The difference in softening and melting behaviour of these burden materials is directly due to the quantity of molten slag formed in the slag assimilation process. It is indirectly due to the differences in reducibility at temperatures above 1000°C in addition to the composition and volume of gangue before reduction.
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Fumitaka TSUKIHASHI, Nobuo SANO
1985 Volume 71 Issue 7 Pages
815-822
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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The activity of Na
2O in the Na
2O-SiO
2 system was measured at 1 100°C, 1 200°C and 1 300°C for compositions ranging from 33% to 60% of Na
2O. Na
2O-SiO
2 melts were equilibrated with molten leadsodium alloy to maintain the sodium chemical potential in a graphite crucible under one atmosphere of carbon monoxide. The activity of Na
2O was found to vary from 1×10
-7 at 40% Na
2O to 5×10
-5 at 60% Na
2O at 1 200°C. The results agree well with those measured by the electrochemical method.
Since the activity coefficient of sodium in lead-sodium alloy at elevated temperatures which was necessary for the calculation of the Na
2O activity was not available in the literature, it was also measured by equilibrating Na
2O· SiO
2 and Na
2O·2SiO
2 melts, thermodynamic properties of which are known, with carbon-saturated iron and lead-sodium alloy. The activity coefficients of sodium in lead-sodium alloy were found as 0.315 at 1 200°C and 0.582 at 1 300°C.
The activity of SiO
2 in the Na
2O-SiO
2 system was calculated from the activity of Na
2O, using the GIBBS-DUHEM relationship.
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Fumitaka TSUKIHASHI, Fumiaki MATSUMOTO, Tatsuya HYODO, Masaya YUKINOBU ...
1985 Volume 71 Issue 7 Pages
823-830
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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The phosphorus and manganese distribution between Na
2O-SiO
2 melts and carbon-saturated iron and the solubility of nitrogen in these melts were measured at hot metal temperatures by chemical equilibration. Phosphorus distribution increases and manganese distribution decreases with increasing Na
2O content in the slag. The Na
2O-SiO
2-PO
2.5 system was found to have very large phosphate capacities ranging from 10
26.7 to 10
29 at 1200°C. The activity coefficient of FeO in the Na
2O-SiO
2 system ranged from 0.2 to 1.0. The partial pressure of oxygen at the slag-metal interface was estimated to be 10
-17.2 atm at 1200°C from the equilibration test of soda-slag used in the commercial hot metal treatment. Temperature dependences of phosphorus and manganese distribution are expressed as follows:
log(%P)/[%P]=20200/
T-10.9, log(%Mn)/[%Mn]=6070/
T-2.74.
Nitrogen was found to dissolve into Na
2O-SiO
2 melts as CN
- from the dependence of solubility on the nitrogen partial pressure when graphite coexists, as expressed by the following reaction:
1/2N
2+3/2C+1/2O
2-=CN
-+1/2CO.
The solubility of nitrogen increased with raising temperature and the Na
2O content in melts.
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Fumitaka TSUKIHASHI, Anders WERME, Akira KASAHARA, Masamichi OKADA, No ...
1985 Volume 71 Issue 7 Pages
831-838
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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The vanadium, niobium, antimony distribution between Na
2O-SiO
2 melts and carbon-saturated iron were measured in the temperatures range from 1 200°C to 1 350°C. Those for vanadium and niobium increased with increasing the Na
2O content in melts. Their temperature dependencies for the typical basic composition are expressed as follows;log(%V)/[%V]=2410/
T+0.187, log(%Nb)/[%Nb]=2360/
T+1.34
The predominant species of vanadium under these conditions changed from V
2+ to V
5+ with increasing the Na
2O content, while those for niobium were Nb
4+ and Nb
5+.
The distribution of antimony decreased with increasing the Na
2O content up to 57 mol%, beyond which it decreased. Antimony species changed from Sb
2+ to Sb
4+ as melts became more basic. Since the distribution ratio is too small in this case, it would be impossible to remove antimony from carbon-saturated iron by the soda ash treatment.
The activity coefficient of SbO
1.5 in Na
2O-SiO
2 melts was calculated by measuring the activity coefficient of antimony in carbon-saturated iron in equilibrium with molten Cu-Sb alloys, which was 0.45 at 1 200°C.
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Toshiharu FUJISAWA, Shigeru INOUE, Shigeyoshi TAKAGI, Yoshimoto WANIBE ...
1985 Volume 71 Issue 7 Pages
839-845
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Experiments were carried out using thermally equilibrating and quenching method on the solubility of CaS in the molten CaO-Al
2O
3-CaS slags for the fundamental reference to the shape control of inclusions in steel. On the basis of the results, the activity diagram for this ternary system was determined by thermodynamic considerations. The equilibrium relationships were also estimated among the solute elements in molten steel in accordance with the slag compositions.
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Shiro BAN-YA, Yasutaka IGUCHI, Hiroshi HONDA, Haruhiko ISHIZUKA
1985 Volume 71 Issue 7 Pages
846-852
Published: May 01, 1985
Released on J-STAGE: January 19, 2010
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The heat of mixing of silica(β-cristobalite) with liquid wustite melted in an iron vessel has been directly measured at 1420°C by the modified isoperibol calorimeter(iso-thermal jacket type). Mixing of solid silica with liquid wustite is an exothermic reaction and the measured heat, ΔH
FetO(
l)-SiO
2(β-cristobalite), is about-900cal/mol at the fayalite composition. Heats of mixing of liquid silica with liquid wustite, ΔH
MFetO(
l)-SiO
2(
l), are obtained by the combination of this direct measured results and heat of fusion of SiO
2 in the reference. This result is discussed in comparison with the estimated values by the thermochemical data and by the assumption of the regular solution.
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Shiro BAN-YA, Mitsutaka HINO, Noriyoshi YUGE
1985 Volume 71 Issue 7 Pages
853-860
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Measurements have been made of the equilibrium between H
2O/H
2 gas mixtures and Fe
tO-SiO
2-MnO melts contained in Fe crucible at 1450°C. The influence of slag composition on the activity of iron oxide and the Fe
3+/Fe
2+ratio has been determined. It has been confirmed that the results can be expressed in terms of LUMSDEN'S regular solution model over wide ranges of composition in the system Fe
tO-SiO
2-MnO except for SiO
2 saturation and FeO rich region. The iso-activity lines for each component for these slags in equilibrium with liquid iron at 1600°C have been calculated using the regular solution model.
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Shun-ichi TANAKA, Takaho KAWAWA, Kiyomi TAGUCHI, Akira HONDA, Eihachir ...
1985 Volume 71 Issue 7 Pages
861-868
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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NKK-Davy type No. 4 horizontal continuous caster (HCC) has been installed in Keihin Works in April, 1983. The caster is producing billets such as carbon steels, low alloy steels, stainless steels and high alloy grades billets with 80 up to 330 mm round and 115 mm square.
New technological developments have been made as follows:
(1) The automatic withdrawal modes for large section billet with high oscillation cycle.
(2) The mold conicity design and the break ring made of modified SIALON suitable for the stainless steels and high alloy grades.
(3) The hot-shot-blasting machine to eliminate cold shut cracks on the billet surface.
The application of HCC billets to seamless tubes and pipes, and wire rods for fine wire drawing and for cold-heading and hot forging has brought excellent results.
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Takashi MATSUO, Guan GAO, Yoshihiro KONDO, Ryohei TANAKA
1985 Volume 71 Issue 7 Pages
869-876
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Creep behavior of carbon free 17Cr-14Ni austenitic steels containing tungsten up to twelve per cent has been studied in relation to precipitation processes of μ and Laves phases.
Decrease in minimum creep rate with the addition of up to about three per cent tungsten was attributed to the solid solution strengthening due to tungsten. On the other hand, in the case of steels with more than five per cent tungsten, the remarkable decrease in minimum creep rate was found with increase in tungsten content, and intergranular precipitation of μ phase (Fe
7W
6) was also observed. Then it has been concluded that the intergranular precipitation of μ phase plays an important role in high temperature creep resistance of austenitic heat resisting steels containing tungsten.
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Joo ISHIHARA, Masaichi NAGAI
1985 Volume 71 Issue 7 Pages
877-884
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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This research project has been carried out in order to develop a new material whose dimensional aspects may be little affected during aging while providing excellent wear resistance, high strength, and good machinability. A series of Fe-Ni-Mn age-hardening steels were alloyed with different quantities of vanadium, cobalt, and molybdenum to improve their properties. Dimentional changes and mechanical properties were checked at various conditions of aging and nitriding.
The results are summarized below.
1. When 3 to 10 percent of vanadium is added to these steels, it is possible to reduce dimensional changes almost completely during aging.
2. By adding 10 percent vanadium to these steels, it is possible to limit the expansion of the surface layer within 1 μm during nitriding and the nitrided layer hardness of HV 1 200 can be reached.
3. High strength of 211 kgf/mm
2 may be obtained through Fe-10V-3Mn steel with 2 to 3 percent of molybdenum.
4. The best chemical composition in these steels is Fe-10V-15Ni-3Mn-3Mo. In this steel, tensile strength of 211 kgf/mm
2, matrix-hardness of HV610 and nitrided layer hardness of HV 1 200 are attained by aging for 8 h at 450°C and nitriding for 3 h at 450°C.
A total change in length due to nitriding is usually found to be no more than 1 μm.
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[in Japanese]
1985 Volume 71 Issue 7 Pages
884
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Minoru KITAYAMA, Yasuhiko MIYOSHI, Minoru YONENO, Shigeru NAITO, Kazum ...
1985 Volume 71 Issue 7 Pages
885-892
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Peeling failure of painted electrogalvanized steel immersed in distilled water was investigated. The relation between paint adhesion and water content of painted film was studied in various environments. The effects of NaCl content and dissolved oxygen in water on paint adhesion were studied. Delaminated surfaces after peeling test were analyzed by x-ray fluorescence analysis and electron probe microanalysis.
It was found that;
1) Paint adhesion after distilled water immersion was the worst.
2) Paint adhesion decreases with increasing NaCl content.
3) Dissolved oxygen affects little paint adhesion.
4) The amount of phosphorus remaining on electrogalvanized steel did not vary during water immersion test and was less than that on cold rolled steel.
5) There is no difference between water content of painted electrogalvanized steel and that of painted cold rolled steel.
The peeling failure of painted electrogalvanized steel in distilled water will not be initiated by corrosion under the film but will occur due to delamination of paint film by higher osmotic pressure of the dipped solution.
As the pressure under the paint film on electrogalvanized steel is thought to be the same that on cold rolled steel, it seems that the weakness of breaking strength of conversion film or adhesion between conversion film and steel surface will cause the poor paint adhesion of painted electrogalvanized steel immersed in distilled water.
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Noboru ISHIKAWA, Toshiaki FUJIMORI
1985 Volume 71 Issue 7 Pages
893-900
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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A new testing method is proposed which may evaluate the quantity of A-type MnS inclusions in rolled steels. This method is characterized by scanning on the lattice points assumed on steel plates.
An experimental study about the performance of this method has been performed.
Results obtained are as follows.
Mean echo height (
F) is correlated with the ratio (
ARc) of the projected area of inclusions to the scanning area of steels.
The pitch of the lattice points and the scanning area of steels affect the assurance of results. Therefore, in the inspection of steel frame members, it is necessary for the pitch to be at least 10mm.
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Akihiro ONO, Masao SAEKI
1985 Volume 71 Issue 7 Pages
901-907
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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A new emission spectrometric method in which a spark discharge chamber is linked to a spectrometer by using a fiber-optic light guide has been studied. This report describes the characteristics of various types of fiber-optic light guide for transmission of spark radiation. The analytical system is mainly consisted of spark discharge chamber, power source for spark discharge, Faschen-Runge type spectrometer, 2 to 10m long all silicon types or silicon polymer-clad types of fiber-optic light guide. The loss of transmit-tance by the fiber-optic light guide was investigated by measuring the emission intensities of spectral lines with various wavelength.
The results obtained are summarized as follows: (1) Silicon polymer-clad bundle fiber-optic light guide which has wide numerical aparture and large core area is suitable for transmission of spark radiation, (2) Analytical lines of elements, such as Si, Mn, Cr, Al, Ti, and Cu in Steel, in the range of wavelengths longer than 268nm can be transmitted over a distance of more than 10m and can be determined satisfactorily. However, the transmission of analytical lines of C, P, and S shorter than 268nm is difficult because of the absorption loss by the fiber-optic light guide.
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[in Japanese], [in Japanese], [in Japanese]
1985 Volume 71 Issue 7 Pages
908-909
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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[in Japanese], [in Japanese], [in Japanese], [in Japanese]
1985 Volume 71 Issue 7 Pages
910-911
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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Masatoshi FUKAMACHI
1985 Volume 71 Issue 7 Pages
912-913
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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[in Japanese]
1985 Volume 71 Issue 7 Pages
914-916
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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[in Japanese], [in Japanese], [in Japanese], [in Japanese]
1985 Volume 71 Issue 7 Pages
922-923
Published: May 01, 1985
Released on J-STAGE: June 19, 2009
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