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Volume 22, Issue 10
Displaying 1-16 of 16 articles from this issue
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Hajime Koto, Haruo Watanabe, Michitomo Katô1958 Volume 22 Issue 10 Pages 493-497
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn recent years, the demand for OFHC copper have shown a tendency to increase for use in new field. The effects of the added elements, and of work-strain on its acid resistant properties were described in the 1st and 2nd reports in connection with chill-cast OFHC copper. In this paper, the recrystallization diagram and the grain growth of OFHC copper were determined by mechanical tests and microscopic examinations. The experimental results were summarized as follows: (1) The recrystallization temperature of the OFHC copper was higher than in electric copper as shown in Fig. 5. Accordingly, the value of activation energy of recrystallization was greater than that of the electric copper, and it was found to be about 61700 cal/mol. (2) In the heating temperature range from room temperature to 400°, the recrystallized grains had a tendency to become fine with rising temperature. Moreover, the relation between the grain size and the softening time was linear. (3) The grain growth of OFHC copper began at the lower temperature than that of electric copper, but its velocity slackened at the temperature of about 700°.View full abstractDownload PDF (667K) -
Kazuo Tsuya1958 Volume 22 Issue 10 Pages 497-500
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe present study was initiated to investigate the microscopic structure and the mechanical properties guaranteed on standardized steels. The principal results are as follows: (1) The range of tempered hardness specified in the present Japanese Industrial Standards is narrower than the range of tempered Jominy hardness of standardized steels. Thus, a new hardenability band which is narrower than that specifiied by 2σ is proposed, if the present specified hardness is necessary. (2) The Charpy impact values of standardized steels tempered at 630° are greater than the specified value, whether they are full-quenched or slack-quenched. (3) For the persistence of slack-quenched bainitic structure up to about 40% causes little loss of tempered hardness and ductility. Thus, the impairment of mechanical properties caused by slight slack-quenching appears to be negligible.View full abstractDownload PDF (564K) -
Gunji Shinoda, Tadao Sano, Tadashi Kawasaki1958 Volume 22 Issue 10 Pages 500-503
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA study was made to examine the corrosion characteristics caused by uranyl salt solution, the effect of mechanical stresses on it, and the effect of corrosion on mechanical properties of some austenitic stainless steel. The results were as follows: (1) After the specimens were heated for 100 hr at 680°C, carbide precipitation was more pronounced in Type 316L steel containing Mo and Cu than the others while stainless steel containing Nb has shown always a high corrosion resistance. (2) While the tensile strength of the specimens was unaffected by corrosion, a considerable decrease in their yield point and elongation resulted owing to corrosion, and this tendency was more remarkable in the specimens containing Mo and Cu except the specimen 30A containing Nb. (3) The effect of mechanical stresses on the corrosion characteristics was examined by an auto-radiograph of corroded specimens and it was found that resistance to stress-corrosion of the specimen containing Mo and Cu is inferiour to that of the specimen containing Nb. The corrosion resistance of Nb stabilized steel appears to be almost unaffected by imposed stresses. It may be reasonable to conclude that Mo and Cu in stainless steel are unfavourable for corrosion due to uranyl salt solution while Nb is always beneficial to corrosion characteristics of stainless steel.View full abstractDownload PDF (844K) -
Masazo Okamoto, Ryôhei Tanaka, Akira Satô1958 Volume 22 Issue 10 Pages 504-508
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of Ni,Cu and N content on the properties of 17Cr-4Ni-4Cu type stainless steels were studied from a point of view giving the wrought steels a better combination of strength and corrosion resistance by the co-operation of cold-rolling and age-hardening. The following results were obtained. (1) The Ms temperature is lowered and the retained austenite is increased with increasing content of Ni, Cu or N in the steels. (2) Age-hardening in the tempering of the steels is larger as the Ni content is decreased or the Cu content is increased. Cold-rolling promotes the age-hardening and gives higher hardness. (3) Especially the steel containing N hardens significantly by the rolling and the aging treatment, which probably owes to the superimposition of the large work-hardening intensified by both the formation of martensite containing N and the hardening caused by the precipitation of Cu-rich phase and nitride from the martensite. (4) Increase of Cu- and Ni-content in the steels modifies considerably the resistance of the steels to boiling H2SO4 solution. Solution-quenching at 1000° followed by cold-rolling and tempering at below 440° does not show any deteriorating effect on the corrosion resistance, a result differing from that with 17-7 and 18-8 steels. (5) In the range of the present work the best results were obtained in the steel bearing 17Cr-4Ni-4Cu-0.17N.View full abstractDownload PDF (788K) -
Tokunosuke Nakazima, Masao Takahashi, Hiroshi Kawaguchi1958 Volume 22 Issue 10 Pages 508-512
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe important factor required for the utilization of uranium as a source of atomic energy are the removal of such impurities which show non-fission capture of neutrons as completely as possible.Consequently the production of uranium involves a most searching analysis of such elements. In 1946, B. G. Scribner et al. developed a very sensitive spectrographic method for this purpose, that is, the so-called carrier-distillation method. The method involves the preliminary conversion of the sample matrix to a form having low volatility before the final spectrographic procedures. The authors found that this procedure was the most critical and elaborate, so investigated thouroughly this procedure and distingnished the many factors which may or may not influence the final results. The procedure was applied to the determination of B, Fe, Mn, Mg and Al. High sensitivity, down to 0.05 ppm for B, 7 ppm for Fe, 6 ppm for Mn, 2 ppm for Mg and 20 ppm for Al and also reasonably good reproducibility (±5∼10%) were obtained.View full abstractDownload PDF (706K) -
Toranosuke Kawaguchi, Mitsuru Nagakura, Tetsuro Yamaguchi1958 Volume 22 Issue 10 Pages 512-514
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWhen the preferred axes of magnetization of barium ferrite crystals are oriented to a fixed direction by magnetic field pressing,the value of (BH)max obtained will be high enough, if the barium ferrite has high density and fine crystals. This report contains the basis of processes to produce such anisotropic barium ferrites. The magnetic field applied at the pressing needs to be over 3,000 Oersteds and the pressure should be 1.5 ton/cm2 at least for producing the highest anisotropy and the maximum value of energy, such as (BH)max 2.8×106 Gauss-Oersted. The authors have examined the electron-micrographic structure and shown the mechanism of sintering of barium ferrite to some extent.View full abstractDownload PDF (478K) -
Takao Kawakita1958 Volume 22 Issue 10 Pages 515-517
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe relationship between the structure and the sharpness of razor blades was studied. 1.21% carbon steel tapes were quenched from varying temperature and tempered at 175°. Razor blades were made of these samples and they were tested by string-and paper-cutting tests. It was found that the samples which were quenched from the temperature under Acm showed equal durability in the paper-cutting test. The samples which were quenched from the temperature higher than Acm, showed that the higher the quenching temperature, the less was the durability of the blade. The writer tested also the 13Cr stainless steel razor blades. These blades lost their sharpness rapidly in the initial 3 times’ paper-cutting tests but thereafter showed good durability as compared with the carbon steel blades.View full abstractDownload PDF (538K) -
Masao Terasawa1958 Volume 22 Issue 10 Pages 517-520
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this paper,the author describes the results of some bending property tests of lead-silicon and lead-antimony-silicon alloys at room temperature. The results obtained were as follows: (1) In Charpy impact tests of U notched specimens, the properties of lead-silicon alloys were not improved by the silicon content, but the properties of lead-antimony-silicon alloys were improved by it. (2) In reverse bend tests of as-cast and as-extruded round bar specimens, the properties of lead-silicon alloys were improved by the silicon content, especially the as-cast alloys showed better results than the as-extruded alloys, and the properties of lead-antimony-silicon alloys were improved by the silicon content in the range of low antimony contents. (3) In repeated fatigue tests of extruded round bar specimens, the properties of lead-silicon alloys and lead-antimony-silicon alloys were improved by the silicon content.View full abstractDownload PDF (449K) -
Yôtaro Murakami, Toshio Enjyô1958 Volume 22 Issue 10 Pages 521-525
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe titanium-molybdenum alloys containing 12.2, 7.47 and 2.14 wt%Mo were studied to understand the principles of heat treatment of titanium alloys for the three basic conditions of heat treatment; (a) Water-quenched state. (b) Quenched and reheated state. (c) Isothermally transformed state, chiefly by differential dilatometric method, and also by hardness measurement, X-ray analysis and microscopic observation. By water-quenching 12.2 and 2.14 wt%Mo alloys showed completely retained β and martensite structure respectively, and 7.47 wt%Mo alloy appears to be a mixed structure of them. The hardening and softening reactions are apparently associated with the decomposition of the β-titanium phase and precipitation (ω or α). It was also found that these reactions were accompanied by considerable volume change. The decomposition of martensite structure was also accompanied by volume change, but had little effect upon hardness.View full abstractDownload PDF (893K) -
Masao Kondo, Takehiro Shibaki1958 Volume 22 Issue 10 Pages 525-528
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWhen carbides in some hardened samples of bearing steel are electrolytically isolated in 0.2 N-HCl+5% citric acid or 0.5 N-HCl, the isolated residue often contains a large amount of metallic iron. In our research, metallic iron in the residue was measured with HgCl2 solution, and Cu, Sn and As in the steel and the residue was determined. The results obtained were as follows: (1) Steel that contained much metallic iron in the residue contained a comparatively large amount of Cu, Sn, or As. (2) Almost all the Cu, Sn and As contents in the steel was come out in the residue, and Cu and As could be separated from the residue quickly with 1%KCN solution. The authors were led to conclude that the Cu content in the steel covered partially the surface of the sample, and prevented perfect isolation of the carbides, the metallic iron was found present in the residue.View full abstractDownload PDF (508K) -
Mayumi Someno, Hisaya Nagasaki1958 Volume 22 Issue 10 Pages 528-532
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSMolybdenum silicides formed by heating molybdenum powder or stoichiometric mixtures of MoSi2, Mo3Si2 and Mo3Si in atmospheres containing silicon tetrachloride gas were examined by X-ray analysis. Above 900°C, molybdenum powder reacted with silicon tetrachloride gas and formed various silicides in a hydrogen atmosphere but did not react even at 1300°C in a neutral atmosphere. In the case of st oichiometric mixture of MoSi2, the silicide MoSi2 was formed above 1300° when heated in a pure hydrogen gas, but it was formed at a lower temperature such as 900° when heated in a hydrogen or nitrogen atmosphere containing silicon tetrachloride gas. The X-ray diffraction lines of MoSi2, Mo3Si2 and Mo3Si showed a good agreement with the past descriptions.View full abstractDownload PDF (713K) -
Zenji Nishiyama, Ken-ichi Shimizu, Muneo Oka1958 Volume 22 Issue 10 Pages 532-536
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSUsing high manganese steel samples that were cold-worked at room temperature and revealed strain markings, X-ray examination has been performed, but no positive result has been obtained to confirm the occurrence of the different phases. According to our electron-microscopic observation, the strain markings are grooves of a triangular section composed of two planes, the intersection of which forms the depth of a sharp line. The sharp depth is assumed to be a trace of a very thin platelet of ε-phase passing through it. The presence of the thin platelets is considered to be acause of the work hardening.View full abstractDownload PDF (1312K) -
Ichiro Fukumoto, Norio Shibata1958 Volume 22 Issue 10 Pages 536-540
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAlloy white irons with Ni,Cr or both elements were cast in iron, sand and preheated silica tube mould. As to these as-cast specimens and the heat-treated ones, Ni or Cr% in cementite, electrolytically separated, the area% of primary crystal in microphotograph, and Ac1 or Ar′ temperatures were measured. The results are summarized as follows: (1) Concentration ratio of Ni in cementite residue (γNi), separated from the cast specimen, become lower and that of Cr (γCr) higher, when the specimen is heat-treated for a comparatively short time. (2) The higher the cooling rate of casting, the lower γCr, and the higher γNi. (3) Yield of cementite residue depends upon the shape, size and structure of primary crystal. (4) The Ac1 and Ar′ temperatures of castings are raised by annealing at 800° or 900°C, and this depends partly upon the variation of Cr or Ni% in primary crystal by the treatment, especially Cr%.View full abstractDownload PDF (814K) -
Tadakazu Sakurai, Hisashi Izumi, Tadashi Kawasaki1958 Volume 22 Issue 10 Pages 540-544
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA study was made to investigate the effects of stress imposed on the specimen during tempering treatment upon the mechanical properties of carbon steel. As the tempering is carried out on hardened steel under stresses, the treatment may be called “Stress-tempering”. The results obtained were as follows: (1) When stress-tempering was carried out under stresses above the yield point of the specimens at each tempering temperature, the proportional limit and the 0.2% yield strength of the specimens were remarkably improved, as compared with those of conventionally tempered ones. (2) In stress-tempering, the lower the tempering temperature and the lower the carbon contents of the steel, the stronger is the effect of stress upon the mechanical properties of steel. (3) By stress-tempering at a relatively low temperature (100∼300°), it was possible to increase both the proportional limit and 0.2% yield strength of steel while keeping their high tensile strength and hardness. (4) By applying stress-tempering to low-carbon steels, it was possible to give them a high strength which can bear comparison with that of hardened and tempered high-carbon steel. From the above experiments, it seems that stress-tempered low-carbon steel can be used for springs, wire-ropes and others in the place of high-carbon steel.View full abstractDownload PDF (842K) -
Masashige Koyama1958 Volume 22 Issue 10 Pages 544-548
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe relation between the impurity substructure (corrugation) and the misorientation substructure (e.g. striation) microscopically observed in single crystals grown from the molten tin along the [110] direction, was investigated by means of X-ray diffraction microscopy. The influence of the speed of growth and the temperature gradient upon the substructures, was also examined. In the specimens grown at low speeds (e.g. 0.05 mm/min), in which no continuous corrugations were observed microscopically, there appeared reticulate subboundaries of irregular shape, but no linear subboundaries. At higher speeds (e.g. 0.3 mm/min), a few linear subboundaries developed from some of the reticulate subboundaries. Further, the linear ones increased in number with higher speed of growth and steeper temperature gradient.View full abstractDownload PDF (843K) -
Akito Yoshida1958 Volume 22 Issue 10 Pages 548-552
Published: 1958
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe equilibrium between molten slag and oxygen atmosphere was studied by a statisticothermodynamical method. The number of mols of T. FeO, FeO, Fe2O3, CaO, SiO2 of slag was C1, C++, C+++, C2, C3, respectively. From the structures of silicate, ferrite and hematite, the author has established the model of molten slag as follows:—(1) The present molten system has two lattices I and II having N(C1+C2+C3) each. (2) The positive ions are situated at lattice I and lattice II, and the ions at I and II have 4 and 6 neighboring O−−, respectively. (3) NC+++ Fe+++ and NC3 Si4+ are situated at lattice I, and NC+++ Fe+++, NC++ Fe++ and NC2 Ca2+ at II at random, respectively. (4) The potential energy between neighboring ions varies with the composition of slag, for instance the potential energy \varphi++−0 of Fe-O varies with concentrations of ε2 and ε3 of CaO and SiO2 as follows: \varphi++−0=\varphi++−00+ε2\varphi++,2+ε3\varphi++,3+ε2ε3\varphi++,2,3. From this model, the Gibbs’ free energy of molten slag was obtained and the equilibrium between molten slagslag and O2 atmosphere can be expressed by the following equation.
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From this equation the equilibrium between molten slag and O2 atmosphere has been explained quantitatively in the extensive range of oxygen pressure from 10−8 to 1 atm, of temperature from 1383 to 1648° and of the compositions of the Fe oxide -CaO-SiO2 system.View full abstractDownload PDF (721K)
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