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Volume 18, Issue 10
Displaying 1-14 of 14 articles from this issue
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Kiyokazu Ogawa, Eiichi Tsuji1954 Volume 18 Issue 10 Pages 499-503
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this paper we measured the depths of stressed layers and the roughness of the machined surfaces of various steels and found the results as follows. In turning operations, the depths of stressed layers were decreased by increasing the cutting velocity and the carbon content for plain carbon steels, but increased by increasing the cutting velocity and the nickel content for nickel chromium steels. The roughness of the turned surface was improved by increasing the cutting velocity for all kinds of steels. In grinding operations, the depths of stressed layers were less than those of the turned surfaces and these values were nearly constant for all carbon steels.View full abstractDownload PDF (825K) -
Isamu Igarashi, Katsuya Ikawa1954 Volume 18 Issue 10 Pages 504-509
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of Ni, Ti and Mo on the solidification process of hypo-eutectic Fe-C alloy were investigated. The alloys containing some percentage of Ni have eutectic graphite structure when rapidly cooled, sometimes accompanied by ledeburite. These were discussed from the experimental results. In Fe-C-Ti alloy, when cooled in a furnace, eutectic graphite structure was obtained in alloy with 0.3∼1.4% of Ti, and mottled structure in alloy with more than 1.5% of Ti, the thermal analytical curves of which were characteristic in both cases. Lastly, some addition of Mo to Fe-C alloy caused mottled structures with peculiar cooling curves.View full abstractDownload PDF (1631K) -
Tomoo Satô, Hideo Kaneko, Katashi Masumoto1954 Volume 18 Issue 10 Pages 509-513
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to supply fundamental data for the production of cuprous oxide rectifiers of high quality, the effects of non-metallic and gaseous elements included in copper on the rectifying properties were studied. In this study, the measurement of the rectifying characteristics, their temperature dependence and the change of forward current at 0.8V and reverse current at 6 V in running test was carried out and the following results were obtained: (1) When the copper contains 0.1% P, it is impossible to make rectifying disks mainly because of nonadherence of the oxide layer. As increasing the phosphorus content is increased from 0.001% to 0.01%, the rectifying resistance increases in the conducting direction, while it decreases in the reverse direction. (2) With the increase of sulphur content from 0.001% to 0.1%, the rectifying re istance decreases in both directions. (3) When copper contains oxygen corresponding to 1.5×102 mm HgO2, the rectifier shows the highest efficiency, in comparison with copper containing various other elements. (4) By increasing the chlorine content from 0.01% to 10%, the rectifying resistance decreases in both directions and on introduction of 0.0002% Cl2 into the first heat treatment furnace improves the rectifying characteristics. (5) The forward current in running test increases in the first few minutes, but afterwards it is kept almost constant. (6) The creeping percentage increases fast in the first few minutes and afterwards gradually. A rectifying disk containing 0.01% P or 10% Cl shows high creeping property.View full abstractDownload PDF (638K) -
Tomo-o Sato, Hideo Kaneko, Katashi Masumoto1954 Volume 18 Issue 10 Pages 513-515
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe measurement of the rectifying characteristics, their temperature dependence and the change of conducting current at 0.8 V and reverse current at 6 V in running test of copper rectifying disks containing lead and thallium were carried out. The following results were obtained: (1) With the increase of lead content from 0.001% to 0.01%, the rectifying resistance increases both in the conducting and reverse directions. (2) By increasing thallium content from 0.001% to 0.1%, the resistance generally decreases in both directions. (3) The conducting current in running test increases in the first few minutes, but afterwards it is kept almost constant. And the increasing percentage of the current decreases with the increase of lead or thallium content. (4) The creeping percentage increases remarkably in the first one or two minutes and afterwards only gradually. A rectifying disk containing thallium shows high creeping property. By summarizing our previously published papers (1)-(4) and the present one, impurity elements in copper for cuprous oxide rectifier can be classified as follows:
(1) Oxygen, sulphur and selenium decrease the rectifying resistance in the conducting direction. (2) Nickel increases especially the resistance in the reverse direction. (3) Zinc, tin, lead, thallium, tellurium and bismuth scarcely have any effect upon the rectifying efficiency. (4) Hydrogen, chlorine, phosphorus, silicon and silver give low efficiency.View full abstractDownload PDF (458K) -
Kazuo Hori1954 Volume 18 Issue 10 Pages 516-519
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe changes of viscosity in molten metals were measured in neutral or vacuum atmospheres and then, these values were found unrelated with runnability. But this was clearly unreasonable, because metals melted in air absorb a few gases and the viscosity of metals containing these gases should be measured in relation with runnability. The flowing down method was adopted by the author in this report and a few remarkable results were obtained as follows. (1) The viscosities of molten metals in neutral atmosphere proved to show a large differences from the viscosities measured in air and the former showed a decreasing inclination with increasing temperature and the latter an increasing inclination. Near the upper ranges of melting point, the viscosities measured in air indicated lower values than in neutral. (2) The effects of max. heating temperature for viscosities by melting in air gave a remarkable change and the pec liar values were given at every temperature and the effects of different specimens were recognized. (3) Similarly, the effects of holding time at every temperature were conspicuously recognized and in both specimens, a large increase of viscosity was given by 60 min holding. (4) The changes of viscosity by melting in air indicated the perfect reciprocal relation with the results of runnability measured in the same conditions, and it was clarified that the change of runnability was essentially under the control of the change of viscosity in liquid metal based on the gas absorption by melting in air.View full abstractDownload PDF (745K) -
Takuichi Morinaga, Hiroshi Hagihara, Masao Ikeda, Shigetaka Kashima1954 Volume 18 Issue 10 Pages 520-522
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAs has already reported, the difference of the cooling velocity between the upper and lower part of a slab or billet will cause many defects, such as crack or streak upon cold working. Gases evolved on combustion of rice-bran during the pouring of melt attack the soldified skin, resulting in defective areas. Incorrectly by added moisture to a mould may be more deterimental than other faults, because if the added moisture is too low, a carbonization of rice-bran is promoted, particularly if a mould is subjected to high casting temperature. A slab or billet formed under such a condition has an undesirable property for cold working. To avoid this disadvantage, a close attention to the procedure of casting and moulding is required. The results obtained are as follows: (1) An amount of new rice-bran added to a mould has a remarkable influence upon solidification. (2) With high temperature casting, the volume of gases evolved during the pouring of melt increased. (3)A boundary between the pillar and the granular crystals appearing in a slab or billet is beyond control by a change of the thickness of rice-bran.View full abstractDownload PDF (418K) -
Shiro Ogawa, Denjiro Watanabe1954 Volume 18 Issue 10 Pages 523-527
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt is a well-known fact that titanium has an excellent oxidation- and corrosion-resistance. We have examined, by the electron diffraction method, surface films formed on titanium attacked by several acids at various conditions. Diffraction patterns obtained from the surfaces attacked by HF, HCl, H2SO4 and H3PO4 showed rings due to f.c.c. lattice which may be deduced to occur from TiH2. When these specimens were heated in vacuum at 450∼800° for a few hours, the rings due to titanium and to TiC (NaCl-type) appeared. From this fact, we have confirmed that TiH2 formed on the titanium surface is decomposed in vacuum at high temperatures, as Gulbransen et al pointed out. When the specimens treated in this way or rolled specimens were immersed in HNO3 at room temperature for 4∼10 days, just hexagonal diffraction rings due to titanium only were obtained, and we started from these surfaces observations to further experiments. When the specimens were attacked by boiling HNO3 and aqua regia, the surface films consisted of TiO2 (anatase),but when attacked by boiling 10% CrO3-solution films of TiO2 (anatase+rutile) were found. The surfaces attacked by boiling 10% FeCl3-solution for one hour gave many sharp Debye rings; however, the crystal structure of this film has not been determined at the present stage.View full abstractDownload PDF (897K) -
Hisao Wakashima1954 Volume 18 Issue 10 Pages 528-531
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSElectron microscope has a very large depth of focus and this character is very suitable for the study of microstructure of fractured surfaces of metals. Neverthless, very few electronmicroscopical studies of fracture of metals have been reported until now. This is due to the difficulty of obtaining faultless replica of fractured surfaces. We removed this difficulty by adopting an improved methylmethacrylate-Al replica. In this method, the first step replica of polymethylmethacrylate-Al is obtained by dissolving away the metal substance by dilute acid, and next Al on this first step replica rotated during the procedure is evaporated. By this method satisfactory replicas of fracture surfaces of metals were obtained.View full abstractDownload PDF (916K) -
Hisao Wakashima, Shin Uemura, Motomu Takahashi1954 Volume 18 Issue 10 Pages 532-535
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe fractured surfaces of steel were studied electron-microscopically, using the replica technique described in the previous report. (part 1)
The fractured surfaces of ductile materials such as pure iron and low carbon steel consist of small domains whose dimensions are 1∼10 μ in diameter. The boundary of this domain may correspond to the microcrack which is at first induced in the material in the process of fracture. On the contrary, the fractured surfaces of mild steel after fatigue test contain many streaks of crack originating from grain boundaries. Brittle materials such as high carbon steel or quenched Ni-Cr steel have very flat fractured surfaces, and the domains in these surfaces are larger than those of ductile materials. The mechanisms of fracture in brittle materials are unknown unless the relation between the fractured surfaces and the structure are completely investigated.View full abstractDownload PDF (1292K) -
Tadashi Kawasaki, Gunji Shinoda, Yukizumi Kita1954 Volume 18 Issue 10 Pages 535-539
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe changes of hardness and magnetic properties of mild steel (0.18% C) and commercial pure nickel due to quenching were investigated. When mild steel specimens are quenched hardening (mechanical and magnetic) occurs by enormous thermal stress by which slips take place at the outer layer of specimens, and at the same time, softening occurs. So when mild steel is quenched at a sufficiently low temperature, such as 100∼250°, hardening and softening is just balanced, while remarkable hardening is observed in a specimen which has been quenched at a temperture higher than about 400°. This is not the case with nickel specimens, in which hardness-change mainly depends on the thermal stress alone. The magnetization curve decreases its slope by quenching, but when a certain external tension σc was applied at a temperature below the recrystallization temperature all show the same magnetization curve; because residual compressive stress in a quenched specimen diminishes by external tension and therefore if the quenched specimen is stretched, it will act as if a stretched annealed specimen will do. When the quenching is done at a temperature higher than 450°, such coincidence of magnetization curves are not observed, and perhaps it is because that the higher the heating temperature the more the complicated distribution of residual stress becomes.View full abstractDownload PDF (690K) -
Kinji Yokoyama, Tsuneo Matsukura1954 Volume 18 Issue 10 Pages 539-542
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe change in magnetic intensity of a high-C high-Cr steel containing 2.11% C, 13.23% Cr was measured by a magnetometric method under different heat treatments and the cause of such change was studied. The experimental results are summarized as follows: (1) The intensity of magnetization after quenching became smaller as the quenching temperature became higher in the case of quenching both in air and in oil. Especially, in the case of quenching in oil or in air from 1130°, almost no magnetization was observed, which revealed that it has entered a 100% austenite state. (2) When a specimen quenched in oil from 950° or 1050° was heated, there was observed an increase in the intensity of magnetization at around 300°. In the case of the specimen oil-quenched from 1130° such change was not perceived. (3) Specimens oil-quenched from these quenching temperatures represented a remarkable change in magnetic intensity at around 700°. From the previously informed results of the dilatometric experiments etc, it was obvious that his should be due to a γ→α transformation owing to a decomposition of the residual austenite. On the cooling curves, moreover, no change in the magnetic intensity was observed which would correspond to a precipitation of ferromagnetic carbide and others. (4) As results of the measurement on the change of magnetic intensity versus tempering treatment, it was found that the transformation of austenite was the easier in the case of the lower, temperature of quenching. Besides, in the case of the equal temperature of quenching, its transformation was the easier as the tempering temperature was the higher and as the holding time in tempering was the longer. These results well coincided with the previously informed results of both the dilatometric experiment and the measurement of the electric resistance with the same steel.View full abstractDownload PDF (720K) -
Yoshitsugu Mishima, Shigeju Morikawa, Sadamu Yamanouchi1954 Volume 18 Issue 10 Pages 543-547
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAs the results of the previous studies, three anomalies are now known to exist in Cu-Zn alloy; (1) socalled anomalous hardening, found to occur in several Cu or Ag alloys when they are low-temperature annealed after cold working to some extent, which was fully discussed in the authors’ first report in 1952. (2) secular change after cold work, which occurs at room temperature in cold rolled Cu alloys, (3) The so-called secular change, well-known to occur in Cu alloys containing Zn, after they are low-temperature annealed. Experiments were carried out to examine the behavior of the change (2) with several Cu alloys among which anomalous-hardenable alloys were included. The result shown in Fig. 2 was then compared with the behavior of the change (1) in Fig. 1, reproduced from the first report. Next, secular change after rolling for the longer periods up to 5 months at room temperature was observed, as illustrated in Fig. 3; general softening as well as homogenization of strain could be seen. A similar homogenization was also observed when α-brass was annealed at 180° after cold work, but no softening could be observed so far as recrystallization did not begin. Last of all, but none the less important finding was obtained when cold working was carried out above room temperature up to 200°. Clear difference was confirmed between the changes (1) and (2) (Fig. 5 and 6). Extreme softening was observed when anomalous hardening was interrupted and the brass rolled at higher temperatures was subsequently kept at room temperature. From these observations, it will be concluded that the two changes (1) and (2) should be considered seperately, as several differences can be pointed out as discussed at the end of this report.View full abstractDownload PDF (933K) -
Seji Miyake1954 Volume 18 Issue 10 Pages 548-552
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe overvoltage of lead anode was studied in relation to the electrolytic corrosion of buried cable sheath. At the current densities 1∼1000 μA/cm2, the overvoltages were measured in 0.1 N sodium sulphate solutions, then the step-wise potential rise and the increase of resistance polarization at lower potential were observed a linear relation between overvoltage and log-current density was not observed, but in the case of the experiment with an electrode covered with lead peroxide, prepared by electrolysis in high current density, a linear relation was obtained. The total charges carried through unit area of anode was nearly constant for each arrest of potentials. The films of first arrest were highly resistive, and their thickness was about 1100 Å for low current densities. The second arrest corresponded to the growth of very low resistive films of lead peroxide, and oxygen evolved steadily at the third arrest. For high current densities, the total thickness of films was about 1400 Å.View full abstractDownload PDF (923K) -
Yoshinaga Oka, Takuji Kanno1954 Volume 18 Issue 10 Pages 552-556
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCritical study was made on the causes of errors in determining manganese in steel after Volhard method. Solid zinc oxide have a tendency to adsorb manganese ion. Therefore, a large excess of it should be avoided in zinc oxide separation. Potassium permanganate was stable in boiling hot solution at pH 7.08 which was obtained by saturation with zinc oxide. Fading in pink of potassium permanganate observed near the end point of the titration is attributed, therefore, to the consumption of it by manganese ions adsorped on manganese dioxide. Manganese dioxide formed by titration was charged negatively. In the absence of any other positive ion, it adsorbed manganous ions and coagulated. Accordingly low results were apt to be obtained. On the contrary, in the presence of large excess of zinc salt, manganese dioxide adsorbed chiefly zinc ions and manganese ions were left free. Thus satisfactory results were obtained. Adsorption of manganese ion on manganese dioxide and their reaction with potassium permanganate were studied potentiometrically.View full abstractDownload PDF (836K)
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