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Volume 18, Issue 6
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Shiguéo Oketani, Sigemaro Nagakura, Koji Tsuchiya1954 Volume 18 Issue 6 Pages 325-328
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSRésumé: Les auteurs ont étudié les conditions de la formation et la structure cristalline du carbure de nickel (Ni3C) par la diffraction électronique en cémentant les films minces du nickel comme l’un des auteurs avait fait précédemment. (1) La cémentation à 250∼400° dans le courant de CO donne naissance le carbure de nickel (Ni3C) mais il est assez difficile d’obtenir les échantillons homogènes. (2) Les conditions de formation de Ni3C sont délicates à déterminer bien nettement. (3) Entre 300° et 400°, le Ni3C se forme facilement après la cémentation de 5h. (4) Au-dessous de 300°, la vitesse de formation est très petite tandis qu’audessus de 400°, la vitesse de dissociation est grande et on n’observe que le nickel et le carbone (graphitique) dans ce cas. (5) La maille de Ni3C est hexagonale dont la dimension est comme suit: a=2.631 Å, c=4.314 Å, c/a=1.640 Elle est plus petite que celle de Jacobson & Westgren. Cet écart provient ou bien de la différence du mode de préparation du carbure, ou bien de l’erreur de mesure de ces auteurs. (6) Le nickel n’absorbe pas le carbone à la température ambiante. (7) Les grains de Ni3C se grossisse facilement à 400° tandis que le grosseur des grains du nickel ne change pas jusqu’à 500°. Autrement dit, la recristallisation du nickel ne se produit pas jusqu’à 500°.View full abstractDownload PDF (751K) -
Shiguéo Oketani, Sigemaro Nagakura1954 Volume 18 Issue 6 Pages 329-332
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSRésumé.-Les auteurs ont étudié les conditions de la formation du carbure de nickel (Ni3C) en cémentant le film mince de nickel polycristallin dans le courant de CO et les résultats ont été donnés dans leur mémoire précédent. Dans ce mémoire, ils étudient le mécanisme de formation de Ni3C en partant du film de nickel de cristaux uniques. (1) La cémentation se fait beaucoup plus difficilement avec le film monocristallin que le film polycristallin. Ce fait est facile à comprendre parce que la surface où se forme le carbure est beaucoup plus petite pour le monocristallin que le polycristallin. (2) L’orientation relative s’exprime comme suit: & (00,1)_Ni3C \varparallel(111)_Ni
& [10,1]_Ni3C \varparallel[110]_Ni C’est-a-dire le plan le plus compact de nickel est parallèle au plan le plus compact de Ni3C. Ce mode de formation serait général pour le carbure et le nitrure métalliques où les atomes de carbone et d’azote pénètrent interstitiellement dans les métaux. La transition est schématisée à la Fig. 5. Okétani avait trouvé un même phénomène dans le cas de carbure de fer (Fe3C). (3) On peut remarquer que plus la cémentation avance, plus le Ni3C devient polycristallin. Ce fait provient de la contrainte causée par la pénétration interstitielle des atomes de carbone dans le réseau cristallin de nickel. Dans le cas de la cémentation au-dessus de 400°, le Ni3C ne se forme pas mais le nickel de cristaux uniques devient polycristallin. Les auteurs supposent qu’un carbure inconnu se forme à cette température (Ni3C2 de Bahr & Bahr ?), qu’il est instable au-dessous de 400° et qu’il se décompose à la température ambiante en laissant le nickel polycristallin et le carbone presque amorphe. Cette supposition doit être vérifiée ultérieurement.View full abstractDownload PDF (680K) -
Hikozô Endô, Namio Ohtani1954 Volume 18 Issue 6 Pages 333-337
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe authors have investigated the galvanic corrosion of mild steel in contact with phosphorus bronze in Na2SO410H2O and Na2CO3 alkaline solutions at 30° and interpreted the relation between the potential difference of both metals, the specific resistance of solutions, the solubilities of corrosion products, the polarization and the galvanic corrosion loss ΔW of mild steel, by introducing the following equation:
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Furthermore the following items were cleared up.
(1) In stagnant state, the maximum point of ΔW is at pH=10.5 in Na2CO3 solution. At pH<10.5, ΔW is controlled mainly by V, γ and cathodic depolarization, but at pH>10.5, it is controlled mainly by decrease of V and anodic polarization. (2) In Na2CO3 solution, the decrease of ΔW of mild steel with increase of r.p.m. is based on the decrease of V and anodic polarization. The fact that the pH value at which the maximum point of ΔW is obtained shifts to smaller values by revolution seems to be caused by anodic polarization due to the increase of diffusion amount of OH−. (3) On the contrary, in Na2SO410H2O solution, ΔW increases by revolution and this is because anodic polarization is affected differently by the difference of anions (CO3−− or SO4−−) in the solutions.View full abstractDownload PDF (793K) -
On the Cathodic Protection of Metals (2nd Report). On the Cathodic Corrosion of 18-8 Stainless SteelGorô Itô1954 Volume 18 Issue 6 Pages 338-341
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSEffect of cathodic current on the corrosion of 18-8 stainless steel in various acid and salt solutions was studied. It was found that 18-8 stainless steel suffers cathodic corrosion at certain current densities in dilute HCl, HNO3, H2SO4 and NaCl solutions, but this corrosion can be protected by higher cathodic current as shown in Fig. 3, 5, 6 and 7. This cathodic corrosion is due to the breakdown of protective oxide film on 18-8 stainless steel by hydrogen evolved on the cathod surface by electrolysis of the solutions, but such active stainless steel can be protected by a higher cathodic current. This mechanism is schematically illustrated in Fig. 8a and 8b.View full abstractDownload PDF (557K) -
Shigeo Ôwaku, Hideo Akasu1954 Volume 18 Issue 6 Pages 341-344
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWith a view to establishing the quenching process for high speed steel, the authors have obtained the C.C.T. curve for 18-4-1 high speed steel (JES SKH 2). The experimental procedure follows: The surface except the end faces of a specimen is completely coated with thermal insulator. The whole piece is heated to 1300°, then put into the electric furnace with a predetermined temperature except the open end 10 mm long which is kept out of the furnace. In this state the exposed part is allowed to cool in still air while the inserted part is also cooled in the furnace at a slow rate. Thus the cooling curve of end quench is obtained. Similar specimens are cooled under the same conditions, their structures at various phases fixed, and their microstructures and hardnesses examined for determination of the C.C.T. curve. The results show that the temperature at which super-cooled austenite is most unstable is about 720° and critical cooling velocity, about 17°/min.View full abstractDownload PDF (742K) -
Yugorô Ishii1954 Volume 18 Issue 6 Pages 345-350
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe success of brazing depends upon the properties of metals to be joined and the interaction between them. For example, solid solutions, eutectic reactions or intermetallic compounds make brazing successful. The strength of joints is affected by geometrical conditions caused by the above-mentioned phenomena, and monotectic or peritectic reactions during solidification. Adhesion by internal change in the boundary crystals and dipole-moment can also be an important factor of strengthening. Various types of diffusion were studied in conjunction with the strength of brazed joints. Metals which were difficult to braze are shown to be successfully brazed by means of an expedited diffusion in which, for example, a small quantity of additional metals is employed on the brazing surface in order to be diffused and adsorbed. Volume and grain boundary diffusions affect the strength of brazed joints. When brazing alloys are used, the strengths are affected especially by the selective diffusion of alloying elements. All types of diffusion occur preferrably along certain crystallographic planes. In the present paper it has been discovered that atoms of a metal diffuse more readily along a certain special direction in a crystallographic plane of a foreign metal. This diffusion may be termed as “lattice internal surface diffusion”.View full abstractDownload PDF (1362K) -
Study on the Aging of Al-Cu-Sn Alloy (2nd Report). The Effect of Sn on the Aging of Al-4.0% Cu AlloyT. Morinaga, M. Yamada, T. Takahashi1954 Volume 18 Issue 6 Pages 350-354
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSBy measuring Vickers hardness, the most effective concentration of Sn on the aging of the Al-4.0% Cu alloy is observed as 0.1% by weight. So later experiments were carried out on Al-4.0% Cu-0.1% Sn alloy. The specimens are soaked at 525° for one hour, the best condition of soaking of these alloys. The aging hardness curves of these alloys are obtained in the shape of two steps; the first hardening is very low but the second is very high in contrast with the hardening of the Al-4.0% Cu alloys. The authors deduced from various of experiments that the first hardening is brought about by the pseudo-precipitation of θ″ and the second by the precipitation of θ′ (and θ) as with Al-Cu alloys. The former reaction is much retarded but the latter greatly accelerated by the addition of 0.1% Sn to the Al-4.0% Cu alloy. From the relation between the aging temperature T in absolute scale and the aging time a maximum hardness in the second hardening is determined, and the actvation energy Q of these alloys is calculated as 21000 cal/mol which will be the same for all Al-4.0% Cu alloys ever obtained.View full abstractDownload PDF (710K) -
Hiroshi Yoshinaga, Shigeru Fujita, Shigeo Minami1954 Volume 18 Issue 6 Pages 354-357
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCarbon in some steel was analysed quantitatively with the quantometer constructed by the authors about two years ago. The error of photometry with this instrument is as small as ±0.2% in short term analysis and ±0.4% in long term analysis. The time necessary for one analysis is only about 20 seconds after the presparking. A Feussner’s spark generator was used to excite the samples, and the spectral line of carbon used in analysis was C III. 2297.59 A, which was measured together with the line Fe I 2297.8 A. In short term analysis, the percent standard deviation of analysis for the samples (concentration 1%∼0.1%) was about 2% and for the samples of low carbon (concentration 0.1%∼0.05%) about 4∼6%. In long term analysis (as in the case of routine work) the deviation increased to about 10%. A method of analysis for the sample containing Ni and Cr (weak lines of these elements overlap the carbon line and cannot be resolved) is explained. The results obtained shows that the quantometer is of practical use for quick analysis of carbon in some kinds of steel.View full abstractDownload PDF (688K) -
T. Nishioka, Y. Yasukuni, M. Kato1954 Volume 18 Issue 6 Pages 358-362
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAuf Stahldrähte mit 0.6% C wendeten wir verschiedene Wärmebehandlungen an und dann zogen diese Drähte bis insgesamt 82% Querschnittsverminderung. Zunächst prüften wir die mechanischen Eigenschaften dieser Drähte, und beobachteten ihre Gefüge durch Metall-und Elektronenmikroskope. Nach dem Ergebnisse dieser Beobachtungen diese Stahldrähte stellen die Gefüge dar, in welchen Zementit und Ferrit sich mechanisch mischen. Den Wärmebehandlungen gemäss haben die Drähte verschiedene Eigenschaften infolge des Unterschiedes der Form, Grösse und Verteilung des Zementits.View full abstractDownload PDF (1233K) -
S. Ôwaku, K. Iijima1954 Volume 18 Issue 6 Pages 362-366
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSRecently, the semi-rapid-heating and quenching method-one of the skin hardening methods—such as induction hardening, flame hardening, etc.—has come to be widely used for simplicity of the process and other features making it suitable for mass production. It is well-known that strength, toughness and wearability of steel are greatly improved by those quenching methods, but these properties of hardened skin itself as compared with those of the ordinarily hardened one have been scarecely known. The Authors have studied the effects of heating temperature and holding time on strength and toughness of semi-rapid-heated and quenched steels. As a result, the followings have been revealed: (1) The strength and toughness of semi-rapid-heated and quenched steel are superior to those of the ordinarily quenched one; this is attributed to lower consistency of mean dissolved carbon in martensite in the former than in the latter on account of a larger quantity of cementite retaiend undissolved. (2) The rate of hardeness decrease by tempering in the former is greater than that of the latter. (3) In semi-rapid-heated and quenched steel, temper embritlement at 220∼240° caused by decomposition of retained austenite did not occur.View full abstractDownload PDF (671K) -
Kinji Yokoyama, Tsuneo Matsukura1954 Volume 18 Issue 6 Pages 366-370
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn view of obtaining the basic data for manufacture of precision tools and gauges, the authors measured the longitudinal change due to the subzero-temperature treatment after quenching with 3 kinds of self-hardening tool steels and an 1.1% C tool steel. The result of measurement was compared with that of the hardness, the intensity of magnetization and electric resistivity; and the cause of the change was studied. Then the longitudinal change of these steels due to aging at room temperature was measured and its stability was examined. The experimental result was summarized as follows: (1) In any steel tested, the degree of increase in the hardness and the ratio of longitudinal change due to the subzero-temperature treatment became larger with rise of the quenching temperature. (2) In each steel tested, the length at room temperature after the subzero-temperature treatment was reduced with the lapse of aging days, and the degree of contraction was the more marked for the steel quenched from the higher temperature. In every steel tested, the degree of contraction due to room-temperature aging was more pronounced in the steel subzero-cooled after quenching than in quenched simply steel. (3) The longitudinal change of the high-C high-Cr steel subzero-treated after quenching due to room-temperature aging was less remarkable than in other kinds of steels tested. (4) In the special tool steel subzero-treated after oil-quenching, the longitudinal change due to room-temperature aging became small by tempering at 150°.View full abstractDownload PDF (835K) -
Eiichi Hata, Katsuzi Takeuchi1954 Volume 18 Issue 6 Pages 371-375
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAluminium sheets of commercial purity were cold-rolled from hot-rolled stocks without intermediate annealing. It was found that the anisotropy of annealed sheets was influenced by hot-rolling condition. During cupping test three types of earing property were observed; i.e., 45° ear, 90° ear and a mixture of 45° ear and 90° ear. The prefered orientation of annealed sheets was investigated by means of X-ray. The recrystallization texture consisted of a (123)-[1\bar21] type texture component and a cube texture component. It was found that the cube texture component increased with decreasing hot rolling-temperature. From the correlation of the results of cupping test and the recrystallization texture, it is assumed that an increase in cube texture component was the cause of 90° earing.View full abstractDownload PDF (780K) -
Isao Gokyû, Hisashi Suzuki, Syunkichi Miyoshi1954 Volume 18 Issue 6 Pages 375-378
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSFundamental studies on backward impact extrusion of zinc shells were already reported. Here, we have, as the continuation, carried out our investigation on the process of aluminium shells. In this report, extrusion forces and properties of the shells are mainly studied. Influences of several factors on extrusion forces, such as influence of “R” of punch, tapering of punch, rate of extrusion, thickness of the wall, annealing temperature of blanks and extruding temperature, etc. are described. And experimentally obtained extrusion forces coincide fairly well with the theoretical values calculated from our formula which we introduced in the first report. Flow test of materials by the blanks in layers, hardness distributions on the wall of shells and the effect of rapid annealing for purpose of softening the thin wall shell are also described. Extruding orientations developed on the side-wall of the shell are the same as in a rolled sheets. Experimental results obtained have almost the same tendency as in the case of impact extrusion of zinc.View full abstractDownload PDF (648K) -
Isao Gokyû, Hisashi Suzuki1954 Volume 18 Issue 6 Pages 379-382
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the fourth report, the extrusion forces and the properties of the extruded aluminium shells were mainly described. In this, we are reporting our studies on earing behaviors of the shells. The ears of extruded aluminium shells formed due to anisotropy of the blanks are too small as compared with zinc that they will have no effects in practice, but their four developing directions are such as at 0° or 90° to the rolling direction by rolled blanks and at nearly 45° by blanks annealed at approximately 300° or more. Thes earing behaviors reverse to the case of deep drawing but the former is clarified by means of crystallographic calculations, considering the influences of flow-resistance on the actual slip systems. Special ears owing to the shape of blanks, formed at the direction of the edge of blanks, are also explained.View full abstractDownload PDF (620K) -
Masao Katô, Kiyoaki Taketani1954 Volume 18 Issue 6 Pages 382-385
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSNow that artificial radioisotopes have become avaiable in any field of science, we used radioisotopes in the determination of concentration of solutions which are too extremely d lute to determine by the other methods. Radioisotope Ag-110, obtained in from of AgCl solution was diluted down to nine stages of aqeous solutions from 1.45×10−9 Ag g/cc to 5.0×10−5 Ag g/cc. These AgCl solutions in glass sample cases were measured at every geometrical position in a sample holder, and the calibration curve for obtained for each Ag concentration. The results were in good agreement with those of calculation, and thus useful for radioactive isotope analysis.View full abstractDownload PDF (616K)
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