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Volume 18, Issue 9
Displaying 1-16 of 16 articles from this issue
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Hikozô Endô, Namio Ohtani1954 Volume 18 Issue 9 Pages 501-504
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSFollowing the previous reports, the galvanic corrosion of zinc in contact with mild steel has been investigated in Na2CO3 and Na2SO4 alkaline solutions at 30° and the relation between the potential difference of both metals, the specific resistance of the solutions, polarization and the weight loss ΔW of zinc have been discussed. The tendency of corrosion of zinc is nearly the same as that of mild steel in contact with phosphorus bronze which was shown in the second report. ΔW becomes minimum at pH=6∼7, becomes maximum at pH=9∼11 and decreases to zero at pH>12.5.View full abstractDownload PDF (520K) -
Tetsuo Yagihashi1954 Volume 18 Issue 9 Pages 504-509
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe system molten copper-oxygen-sulphu is of interest from both the practical standpoints; practically, because this reaction plays an important role in the copper smelting process and theoretically because it contributes to the general development of the laws for solution of triatomic molecules in metals. Therefore in order to establish the mechanism of this reaction in the higher range of oxygen and sulphur content, the author has derived the theoretical formulae as non-ideal solution by the statistical thermodynamical method. Next for compa ing with the experimental results, the values of some unknown constants in theoretical formulae have been determined numerically. Accordingly, a semi-theoretical equation which can be applied over the whole range of temperature of copper smelting and in unsaturated region of oxygen and sulphur in molten copper is given by
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\ oindentwhere x and y are atomic concentrations of oxygen and sulphur in molten copper respectively.View full abstractDownload PDF (817K) -
Miyaji Fujisawa1954 Volume 18 Issue 9 Pages 509-513
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSUsing cylindrical high carbon tool steel or carbonized steel samples, we measured the residual stress of quenching by Heyn’s method, and studied the mechanism of the growth of quenching stress by changing the method of heat-treatment. (1) On full hardening: Factors of growth of residual stresses are non-elastic strains produced by the thermal contraction before the transformation and the expansion caused by the transformation. Residual stresses at room temperature are indicated through their resultants. Non-elastic strains are the plastic deformations produced up to the 10 per cent martensitic transformation in our specimens. Quenching crack which gives rise to discussion in hardening is due to stress cansed by the expansion of transformation. This residual stress is decreased by the depression of cooling rate when a specimen passes the range of transformation and by the rising of temperature in quenching bath. Moreover, this stress is extremely reduced bv the quenching from the temperarure that allows formation of 10 per cent Martensite or Lower Bainite, even if the specimen is quenched in water. (2) On case-hardening: Residual stresses of a case-hardened steel sample are considerably different from those of full-hardened steel samples. These are compression in the surface layer and tension in the core, These are mainly caused by the differences of specific volumes due to the variations of carbon contents in the carbonized steel samples.View full abstractDownload PDF (694K) -
Miyaji Fujisawa1954 Volume 18 Issue 9 Pages 513-516
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn succession to the previous experiments, we have studied the influence of alloying elements (C, Ni, Cr), various heat-treatments and diameters of specimeus on residual stresses of quenched Fe-base alloys by Heyn’s method. The results with full hardening are as follows: Residual stresses of steels are closely related with their cooling dilatation curves. These are much influenced by the expansion caused by the transformation as the transformation point are depressed by the increase of alloying elements. Therefore, these are powerfully influenced by carbon contents. The residual stresses of alloying steel samples are markedly influenced by the carbon contents of austenite when these samples transform at lower temperature. For instance, the residual stress of 21% Ni-Fe alloy samples are different from that of 1.1% carbon steel samples in spite of resembling cooling dilatation curves, i.e. the effect of thermal stress is not apparently recognized in the residual stress of 21% Ni-Fe alloy samples quenched from high temperature. But both the effects of thermal stress and transformation stress are clearly recognized in 1.1% carbon steel samples quenched from the same temperature. Moreover, residual stresses of steel samples containing two or more alloying elements are similar to that of carbon steel samples of the same cooling dilatation curves if these steels contain 0.2 per cent or more carbon contents. Therefore, 0.2 per cent or more of carbon content of high alloying steel samples have a potent effect on susceptibity to cracking.View full abstractDownload PDF (625K) -
1954 Volume 18 Issue 9 Pages 516
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSPlease see pdf. Wrong:stress (kg/mm) Right:stress (kg/mm2)View full abstractDownload PDF (13K) -
Sadao Koshiba, Kazuo Tanaka, Asao Inada1954 Volume 18 Issue 9 Pages 517-521
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSFor isothermal transformation of high speed steel, we investigated the effect of hot bath temperature and holding time on the Ar″ transformation by tempering after quenching, and then the change of intensity of magnetization and dilatometric curve in the hot bath. Results of this experiment are as follows: (1) When the holding was done in hot bath of 250∼300°, the Ar″ transformation was difficult to occur on cooling because lower bainite came to be present, and then this stabilized austenite more. Therefore, more austenite was retained at room temperature and secondary Ar″ transformation on tempering was increased more than by oil quenching. (2) When the sample it was held for a long time in hot bath of 600°, two steps of dilatation were presented on cooling and the retained austenite was decreased at room temperature, and secondary Ar″ transformation on tempering was lowered.View full abstractDownload PDF (737K) -
Sadao Koshiba, Kazuo Tanaka, Asao Inada1954 Volume 18 Issue 9 Pages 521-524
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThis investigation showed clearly the change of tempering curve and intensity of magnetization, and then the relation between the tempering temperature and the hardness of high speed steel that was subzero-treated in −75° after isothermal heat treating at 100°, 300° and 600°. That is, it caused increasing of hardness in 1.5∼2.0 (Rc) and increasing of I∞ because the retained austenite was transformed to martensite to a considerable extent by subzero treatment. Sample heat-treated isothermally for 20 hrs at 300°, was changed scarcely by subzero treatment because the retained austenite was more stabilized.View full abstractDownload PDF (532K) -
Yûnoshin Imai, Tetsuro Ishizaki1954 Volume 18 Issue 9 Pages 524-529
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe present investigation has been carried out to ascertain the effect of nitrogen on the tempering of the coldworked steels. On steels containing various percentage of nitrogen, manganese, aluminium and titauium, the magnetical and electrical properties were measured under the condition of coldworking and tempering. From these investigation it has become clear that; (A) The changes at about 100°, 250° and 400∼550° begins to appear with the addition of nitrogen and become conspicuous as the nitrogen increases. (B) The relief of coldworking stress begins to appear at the temperature of about 300°. (C) The change at about 100° or 250° is due to the precipitation of nitrogen or carbon. (D) The change at about 400∼550° (or 650°) is due to resolution of nitrogen (or carbon). (E) The effect of nitrogen was reduced as manganese increases.View full abstractDownload PDF (785K) -
Yûnoshin Imai, Tetsuro Ishizaki1954 Volume 18 Issue 9 Pages 529-533
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe present investigation has been carried out to ascertain the effect of nitrogen on so-called Hadfield steel for saving manganese by addition of nitrogen. From these investigations the authors conclude as follows: (A) It became clear that the grain size of steels at the steps of casting, forging and quenching, became finer as nitrogen increases. (B) The grain growth at high temperature can be suppressed by addition of nitrogen. (C) The austenite structure becomes stable and the rate of crystallizing out of carbide becomes slower as nitrogen increases.View full abstractDownload PDF (944K) -
Isao Nakamoto, Hiroshi Saito, Katsumi Mizumaki1954 Volume 18 Issue 9 Pages 533-537
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to investigate the behavior of sulfur in raw materials in the manufacturing process of ferro-manganeses by electric furnaces, the amount of sulphide-S, MnS and CaS in slags were determined respectively. (1) Sulphide-S and sulphate-S; There are two methods for determining sulphide-S in slags, namely direct and indirect methods. By the former sulphide-S is evaluated as 82∼95% of total S, and by the l tter as 83∼99.5%. The fact that higher values (1∼11%) are always obtained by the latter, indicates that slags contain sulphide-S which can’t be decomposed by HCl. The sulphate-S content is 1∼17% of total S. (2) MnS and CaS; For MnS, the authors confirmed that Mikhilova’s I2-alc. method is applicable for the case where MnO and MnSO4 coexist. For CaS, Al-amalgam method by Ikegami and Kamimori is also applicable for the case where MnS and FeS coexist. By means of the above two methods, Mn slags are analysed for each component. (a) In high carbon ferro-Mn slags (Mn 10∼15%, wt. ratio CaO/SiO2 1.3∼1.5), sulphide-S, combines as MnS and CaS in the ratio of 65∼80% and 20∼30% respectively. (b) In ferro-Si-Mn slags (Mn 3∼6%, CaO/SiO2 1.0∼1.1) sulphide-S combines as MnS and CaS in tne ratio of 83∼95% and 4∼12%.View full abstractDownload PDF (834K) -
Tasaburo Nishioka1954 Volume 18 Issue 9 Pages 538-541
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn dieser Untersuchung wurden Drähten aus vier Stählen mit Kohlenstoffgehalten von 0.16 bis 0.81% patentiert, gezogen und sodann verdreht. Und dann wurden die mechanischen Eigenschaften dieser verdrehten Drähte geprüft. Von diesen Ergebnissen vermuteten wir, das im Fall der Verdrehung des Stahldrahtes die zwei Wirkungen sich ergeben, nämlich die Wirkung der Formänderung und die Wirkung der reinen Verdrehung. Und falls die Wirkung der Formänderung grösser als die Wirkung der reinen Verdrehung ist: Zugfestigkeit nimmt zu und Dehnung nimmt ab. Falls die Wirkung der reinen Verdrehung grösser als die Wirkung der Formänderung ist: Zugfestigkeit nimmt ab und Dehnung nimmt zu. Patentierter Stahldraht ist des ersteren Falls und Zugfetigkeit nimmt zu. Gezogener Stahldraht ist des letzteren Falls und Zugfestigkeit nimmt ab.View full abstractDownload PDF (980K) -
Akira Adachi, Shoji Fujimoto1954 Volume 18 Issue 9 Pages 542-545
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAdsorption and desorption from the acid pickling solution with organic inhibitors such as Xylidine, Laurylamine, Chemisol and commercial corrosion inhibitors—Picknoc (Japan), Ibit (Japan), Rodine 120 (U.S.A), Henkel (Germany), on mild steel were measured. Laboratory tests to measure (1) the loss in weight of metal (specimens of hot-galvanized mild steel sheets) in 1N-H2SO4 solution with and without inhibitors, (2) the amount of hydrogen evolved in the same case as (1), (3) the effect of the inhibiting film on the electrode potentials of adsorbed metallic surfaces in 1N-HCl solution against N-Calomel electrode, (4) the galvanic current between the adsorbed or desorbed metallic surface and Pt electrode in 1N-HCl solution with electrodes of 1 cm2 and 1 cm appart by with a milliammeter were carried out. The surface activities on mild steel measured with these electrochemical procedures are determined and compared with other results (weight loss and H2 evolution). The initial potentials are measured with an oscillograph and steady state potentials are measured with potentio-meter. Desorption of inhibiting films on mild steel are studied—dipping and washing in tap water, boiling water, dilute acid solutions neutral salt (NaCl, Na2CO3) solutions, alkaline solutions and also electrolytic cleaning in alkaline solution. The desorption of inhibiting films are most effective and perfect after electrolytic cleaning. These effects of desorption are measured through electrochemical tests (surface potential measurement).View full abstractDownload PDF (591K) -
Tokutaro Hirone, Kazuo Kamigaki1954 Volume 18 Issue 9 Pages 545-548
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSMeasurements of attennstion of ultrasonic waves in white and annealed cast irons were carried out in the frequency range from 2 to 25 megacycles per second. The attenuations were measured for various stages of graphitization of the cast iron: Specimens were annealed for the purpose of graphitization several times successively and the mesurements were made at each stages of these heat treatments. It has been found that (1) the general feature of attenuation curves is monotonous increase with frequency and (2) with the advance of the degree of graphitization the attenuations increase in the range of higher frequencies.View full abstractDownload PDF (945K) -
Kazuo Hori1954 Volume 18 Issue 9 Pages 549-551
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn a former report, the effects of holding time at max. melting temperature were studied and these are mutually related with heating velocity and max. melting temperature at the same time. Accordingly, this time experiments to clear the effects of heating velocity on runnability was carried out with the change of max. melting temperature and holding time in this time. The results obtained were as follows: (1) It was cleared that the heating velocity of melting which was neglected hitherto had an important effect upon the runnability and in this experiment, more rapid heating produced a good runnability. (2) As it was mentioned in the former report, the effects of holding time were always influenced by the holding temperature and at lower holding temperature, some holding ti me is necessary to get the best runnability and in higher holding temperature, a short holding produces worse results. (3) The mutual relation between max. melting temperature, holding time and heating velocity was very close and in any cases, the superiority of max. melting temperature on influence for runnability was recognized. After all, it was cleared that a best mutual relation of them exists in any metal and the best runnability will be got under this relation.View full abstractDownload PDF (581K) -
Shigeo Muramachi, Shigenori Hori1954 Volume 18 Issue 9 Pages 552-555
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the previous fundamental experiments, one of the authors studied the phenomenon of the inverse segregation and the results can be summarized as shown in the schematic diagram (Fig. 1.). In the diagram we know the curve consists of two portions A B and C D, and they may be explained respectively by the Super-cooling Theory (AB) and by the Volums Contraction Theory (CD). In this experiments, the authors made a similar investigation of the inverse segregation occuring in industrial Al-Cu (4%) slab ingots, which were prepared by casting in tilting and Züblin moulds. The results show that the mechanism of the inverse segregation which appears in the industrial Al-Cu (4%) slab ingots can be readily explained also by means of diagram (Fig. 1). Furthermore, this diagram suggests that the continuous casting is a very good method for obtaining sound slab ingots.View full abstractDownload PDF (850K) -
Shigeo Muromachi, Shigenori Hori1954 Volume 18 Issue 9 Pages 555-558
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSUsing our continuous casting apparatus, Al-Cu (4%) slabs were made under various coditions, and we investigated the segregation that appeared in the slabs obtained. The results are as follows: The degree of segregation is very low when the conditions of casting—casting velocity, casting temperature, descending velocity and cooling velocity—are suitable. The structure of the slabs is shown in photo. 3; in the photographs we see fine granular structure only as was expected from our diagram (Fig. 1).View full abstractDownload PDF (797K)
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