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Volume 19, Issue 10
Displaying 1-19 of 19 articles from this issue
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Takashi Kimura1955 Volume 19 Issue 10 Pages 567-571
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe most important problem in the study of a transistor is to get higher purity germanium. In this experiment powder-metallurgic method has been applied for that purpose. However, this trial was a failure, because germanium is found to be very difficult to sinter. There remained much voids in the specimens even when they were sintered just below their melting point. On the other hand G. A. Geach reported in his general study the “Theory of Sintering” in Progress in Metal Physics 4 (1953) that germanium did not sinter at 850° as the covalent bond metal is very difficult to diffuse. From our study, we felt a doubt about his explanation. In sintering there did not appear any shrinkage really at that temperature, but the cleavage of the sample showed a shell-like face which is characteristic of germanium, and this revealed a cohestion of particles in the specimen. “Shrinkage” which is auseful measure of sintering could not be found even at α=0.9. The powder used was n-type germanium as it was melted, but, during the process of sintering there appeared no typical change which would indicate a characteristic temperature of sintering, and no n-type sample could be obtained in the case of a sintered sample. However, the electrical resistivity of the a sintered samples began to fall critically at 600° which temperature corresponds to the other characteristic temperature of plasticity, and the value of resistivity was much higher than in a bulk germanium. By metallographical method, the behavior of the voids could be clearly understood. Adhesion phenomena appeared from 700°, the particle assembly began to enlarge and at last voids remained in the specimens near the melting point. There appeared also spherodizing phenomena, and the large voids increased their volume by annexing the small ones. Many such strange phenomena were found in the case of germanium during sintering as compared with other metals.View full abstractDownload PDF (851K) -
Tasaburo Nishioka1955 Volume 19 Issue 10 Pages 571-574
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSDiese Untersuchung hat über die Einfluss der Zugfestigkeit, chemischer Zusammensetzung, Wärmebehandlung und des Ziehen auf die Vickershärte der Stahldrähten eine Erklährung abgegeben. Besonders, um die Beziehung zwischen der Härte und der Zugfestigkeit zu erforschen, habe ich das Verhältnis Hv/σB bei verschiedenen Stahldräten verglichen. Nach den Versuchsergebnissen habe ich die Normalkurven wiedergegeben, welche die Beziehung zwischen der Zugfestigkeit und Hv/σB für verschiedene Gesamtquerschnittsabnahme zeigen. Nach dieser normalen Abbildung besitzt die gewöhnlich hergestellten Stahldrähte für Seil und Feder mit der Zugfestigkeit von 140 bis 180 kg/mm2 ein Hv/σB von rd. 2.5. Das Hv/σB bei gezogenen Stahldrähten nimmt bei gleicher Gesamtquerschnittabnahme mit zunehmender Endzugfestigkeit und bei gleicher Endzugfestigkeit mit steigender Gesamtquerschnittabnahme ab. Ein Einfluss der chemischen Zusammensetzung aufs Hv/σB scheint jedoch nicht vorhanden zu sein.View full abstractDownload PDF (735K) -
Isao Gokyu, Hisashi Suzuki, Tsuyoshi Tada1955 Volume 19 Issue 10 Pages 575-577
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSStudies on cold backward impact extrusion of 0.10% carbon steel were carried out. The results of the experiments were as follows: (1) As the result of testing various lubricants applied on zinc phosphate coating, lanolin and wax proved to be most effective. (2) Under the treatment with such lubricants, the limit of extruding reduction was approximately 50∼60% on 20 mm shells. The specific extrusion force in this case was about 250 kg/mm2 or a little higher. (3) The curves of the impact extrusion force were closely similar to those of non-ferrous metals. Some physical properties of the extruded shells, including their hardness distribution, their microscopic structure, their texture upon extrusion, their tangential residual stress and their tensile strength were also studied.View full abstractDownload PDF (586K) -
Takuichi Morinaga, Yoshio Kato1955 Volume 19 Issue 10 Pages 578-581
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWhen aluminized steel is prepared by hot-dipping method, an alloying layer will be formed on steel in varying thickness from 1.5∼2.5×10−2 mm, consisting of an outer layer of relatively pure aluminium and an inner layer of iron-aluminium compound. The lower the temperature of immersion, the thicker is the pure aluminium and the longer the time of immersion at any temperature, the thicker is the alloying layer. The controlling of this layer has important effect on the various properties of aluminized steel. In the present experiment, the effect of carbon content in steel and of the composition of the aluminium bath on the alloying action between steel and melted aluminium is determined continuously by means of the apparatus as shown in Fig. 1. The results obtained are as follows: (1) By an increase of carbon content in steel, the growth of the alloying layer is restrained markedly. (2) The growth of the alloying layer is not restrained by the addition of 0.1 and 0.4% of Ti, but an addition of 1.0%Ti is effective in preventing the grow of the alloying layer.View full abstractDownload PDF (743K) -
Takashi Ikeno1955 Volume 19 Issue 10 Pages 581-583
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe behaviour of high purity aluminium containing 0.011% of impurities was investigated. The results obtained are as follows: In high purity aluminium, the coarser the grain size before cold-rolling, the more the recrystallization is retarded in completion, and then the recrystallized grain size becomes somewhat coarser. The results of this research on high purity aluminium are similar to those with 99.6% aluminium, as reported previously.View full abstractDownload PDF (637K) -
Hideo Takaki, Masashige Koyama, Hidekiyo Fujihira1955 Volume 19 Issue 10 Pages 584-587
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSLine structures termed “corrugations” and “striations” by Chalmers et al., were studied microscopically with single crystals of tin of the purity of 99.87% grown from the melt, in which the [110] direction was parallel to that of the temperature gradient. The same line structure as corrugations was observed on the side surface of the specimens, and the so-called cell structure was also observed on both the free top surface and the etched sectional one. However, it is noticeable that the line structure observed on the (1\bar10) plane was irregular despite its regularity on the (001) plane, and further that a tortoise-shell pattern was observed on the (110) plane, probably owing to the low purity of specimens. It was also found that the striation boundaries coincided always with the corrugation boundaries on the side surface of the specimens.View full abstractDownload PDF (890K) -
Hideo Takaki, Masashige Koyama, Hidekiyo Fujihira1955 Volume 19 Issue 10 Pages 588-591
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this study, microscopic observations were made with single crystals of tin whose [100] direction was parallel to the direction of growth. Further examination was carried out with respect to the specimens grown in the directions which inclined from [110] to [100] direction, fixing the [001] direction at the angles of 10, 20 and 30 degrees respectively. A“partial dendrite structure,” in which the secondary skeleton developed on the side of growth direction alone, was observed on the (001) plane of specimens whose [100] directions were parallel to the direction of the temperature gradient, probably owing to the low purity. Two kinds of cell structure (one was large and the other smaller) were also observed on both the free top surface and the sectional one of the specimens, having the above mentioned structure. This structure is assumed to be an intermediate structure, when the corrugation changes to the dendrite.View full abstractDownload PDF (852K) -
Mikio Yamamoto1955 Volume 19 Issue 10 Pages 591-595
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt is shown that, for hexagonal, rhombohedral, and tetragonal crystals, the anisotropy of the solution rate along any direction v, and that of the radius vector along the same direction r from the origin to the circumference of a solution body (Lösungskörper in German) produced from an originally sphere crystral, are generally expressed by
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\ oindentwhere vc, va and vb are the solution rates and rc, ra, and rb are the radius vectors along the directions of the c, a, and b axes (the [0001], [11\bar20], and [10\bar10] directions for hexagonal crystal, the [111], [\bar101], and [\bar211] directions for rhombohedral crystal, and the [001], [100], and [110] directions for tetragonal crystal), respectively. θ and \varphi are, respectively, the polar and azimuthal angles of the direction referred to a polar coordinate system of which the polar axis is the c axis and the zero line for the azimuthal angle is the a axis, and n is the order of rotational symmetry around the c axis of the crystal concerned.View full abstractDownload PDF (733K) -
Mikio Yamamoto1955 Volume 19 Issue 10 Pages 595-598
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt is shown that, for cubic crystals, the anisotropy of the solution rate along any direction v, and that of the radius vector along the same direction r from the origin to the circumference of a solution body produced by an originally sphere crystal, are generally expressed by
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\ oindentwhere v[100], v[110] and v[111] are the solution rates and r[100], r[110] and r[111] are ths radiu vectors of the solution body, along the [100], [110] and [111] directions, respectively, and α, β, and γ are the direction cosines of the direction concerned referred to the tetragonal axes.View full abstractDownload PDF (369K) -
Susumu Morioka, Kazutaka Sakiyama1955 Volume 19 Issue 10 Pages 598-600
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of addition of 1∼3% molybdenum as alloy element on the anodic behaviour has been studied in 5% sulphuric acid solution for the binary 18% Cr-Fe, 8% Ni-Fe and 12% Ni-Fe alloys and the ternary 18% Cr-8% Ni-Fe and 18% Cr-12% Ni-Fe alloys, and some of the possible relations between the results obtained and the corrosion-resisting properties of stainless steels containing molybdenum were interpreted.View full abstractDownload PDF (450K) -
Shuichiro Takahashi, Hiroshi Konno1955 Volume 19 Issue 10 Pages 600-604
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe internal friction and the Young’s modulus of Cu-Al alloys with 0 to 16 weight par cent of aluminium were measured at room temperature using free transversal vibration of about 1000 cycles/sec. An alloy of martensitic structure has an extremely high internal friction (1−2×10−3), which is independent of various pretreatments of specimens, such as casting, forging, annealing at 620°, and quenching from 800°, seemingly remaining constant over the frequency range 300 to 7000 cycles/sec and showing a very low Young’s modulus (7.5−8.8×103 kg/mm2).The internal friction of the alloy consisting of α and β′ phases is governed by the quantity of the martensitic structure. The internal friction of α-phase depends largely on the pretreatment of the specimen; its value increases with an elevation of the quenching temperature, and decreases with increasing concentration of aluminium according to a power fuction. The γ-phase has a very low internal friction, and a high Young’s modulus.View full abstractDownload PDF (859K) -
Harujiro Sekiguchi, Michio Inagaki, Seiichi Miyajima, Hirotaka Watanab ...1955 Volume 19 Issue 10 Pages 605-608
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESS(1) The relations between the dimensional changes of carbon steel bars due to heating and cooling and the A1∼A3 or Acm transformations were investigated. (2) If the rate of heating and cooling is either extremely small or large as in air cooling, the percentages of dimensional changes of low carbon steel bar are small, as compared with the case of intermediate cooling rate. (3) It is considered that the banded structure of carbon steel bar is a factor which has influence on these dimensional changes.View full abstractDownload PDF (865K) -
Michio Inagaki1955 Volume 19 Issue 10 Pages 608-612
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESS(1) The dimensional changes of carbon steel bars due to heating above the transformation points and cooling are not attributed to errors of measurement owing to the small pressure of dilatometer-spring. (2) When the steel bars become long and slender, their lengths tend to decrease by heating and cooling, regardless of their carbon contents. However the effect is constant when the ratio of the length to the diameter exceeds a certain value. If the shape of specimen approaches a sphere, such dimensional changes become smaller. (3) It is considered that the carbon content, the microstructure, the dimension (and the shape) of a carbon steel bar are factors which influence the dimensional changes due to heating and cooling.View full abstractDownload PDF (724K) -
Kazuo Tsuya1955 Volume 19 Issue 10 Pages 612-616
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe formation of bainite was observed by using a hot stage microscope, directly and dynamicaly, and the mechanism of bainite formation was qualitatively studied. The results are as follows:—(1) During bainite transformation surface relief effects were observed on polished specimens. It indicates that bainite is coherent with matrix austenite and so its mechanism of formation differs from that of pearlite. (2) The surface relief due to bainite transformation grows slowly and so the bainite transformation differs from martensite transformation. (3) The growth rate, the tilt (Hmax) and the shape of the surface relief due to bainite transformation change continuously as the temperature of transformation changes.
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\ oindent(4) From the experimental results, it is concluded that the bainitic transformation is another mode of transformation, distinguishable from pearlitic and martensitic transformations.View full abstractDownload PDF (1363K) -
Masao Kato, Masatoshi Kobayashi1955 Volume 19 Issue 10 Pages 616-619
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSBy means of stripping emulsion method of radioautography, a study on the behaviour of iron in aluminium of four nine purity was carried out. The alloy was prepared so as to contain 0.064% iron tagged with mixed radioisotopes Fe-59 and Fe-55, the content of which was determined by radiochemical analysis. On the cast form cooled rapidly the greater part of iron was segregated in dendrites, whose structure was difficult to diffuse by solution heat-treatment (600°, 4 hours), and the alloy cold-rolled about 20% revealed a V-shaped slipping pattern. On a rolled structure iron partially dissolved in matrix by solution heat-treatment. It was proved that radioautography was a powerful technique for researches on alloys.View full abstractDownload PDF (727K) -
Ichiji Obinata, Keizô Nishimura1955 Volume 19 Issue 10 Pages 620-623
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSStudying the change in hardness, micro-structures and X-ray diffraction patterns due to annealing of cold-rolled titanium under various rates of reduction, the recrystallization-temperature as well as the mean grain-size after recrystallization have been determined and thus a recrystallization-diagram of titanium is proposed as shown in Fig. 2. The effect of the annealing time as well as the initial grain-size on the size of the recrystallized grains has also been studied: Although, with prolonged annealing time, the grain-size becomes generally large, especially, when the temperature is high, the attainable grain-size seems to be almost constant. The initial grain-size showed very little or almost no effect on the grain-size after recrytsallization.View full abstractDownload PDF (744K) -
1955 Volume 19 Issue 10 Pages 623
Published: 1955
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSPlease see pdf. Wrong:kg·m/mm2 Right:kg·mm/mm2View full abstractDownload PDF (15K) -
[in Japanese]1955 Volume 19 Issue 10 Pages A195-A198
Published: October 20, 1955
Released on J-STAGE: November 11, 2008
JOURNAL FREE ACCESSDownload PDF (544K) -
[in Japanese]1955 Volume 19 Issue 10 Pages A199-A204
Published: October 20, 1955
Released on J-STAGE: November 11, 2008
JOURNAL FREE ACCESSDownload PDF (664K)
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