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Volume 16, Issue 6
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Makoto Hirabayashi1952 Volume 16 Issue 6 Pages 295-299
Published: 1952
Released on J-STAGE: April 04, 2008
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Mikio Yamamoto, Ryôfu Miyasawa1952 Volume 16 Issue 6 Pages 300-304
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSSome experiments were carried out in order to obtain further informations in connection with the production of iron single crystals by the recrystallization method. Round bars, 3∼5 min in diameter, prepared from five materials containing 0.06∼0.13 percent carbon (commercial pure iron and soft steels) were heated up to 1000° in a moist hydrogen stream and then for different time-intervals at that temperature. It was found that a greater part of carbon had already been removed during heating up, indicating that the diffusion of carbon in α-iron is faster than in γ-iron. The degree of grain growth during heating up to 1000° is however, much smaller than that during heating at that temperature. The decarburization velocity is shown to be inversely proportional to the diameter of specimen.
Specimens containing 0.06∼0.015 percent carbon and 40∼90 grains per square millimeter, prepared by the decarburization treatment at 1000° for two days, were elongated to various degrees and then annealed at 880°C for two or three days. The maximum grain growth was obtained with specimens elongated to about 4 percent. The grain growth was found to be independent of the heating velocity in the recrystallization heat-treatment. Especially for specimens of 4 mm diameter, the grain growth was completed by heating at 880° for two days. It is noteworthy that, for the materials examined, the higher is, the purity the more pronounced the grain growth, though it is known that in the especially pure material the grain growth is rather less marked.View full abstractDownload PDF (953K) -
Mikio Yamamoto, Ry\={o}fu Miyasawa1952 Volume 16 Issue 6 Pages 305-309
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe propuction by the recrystallization method of circular-rod single crystals, 3 mm in diameter, from iron-aluminium alloys containing less than 6 percent aluminium was studied in order to find the optimum conditions of the decarburization treatment in a wet hydrogen stream, of the degree of elongation, of the annealing for recrystallization, and of the macro-etching. With the increase of aluminium content, the optimum temperature of the decarburization treatment (for the duration of one day) and the optimum degree of elongation fall respectively from 970°C and 4 percent for electrolytic iron to 900°C and 2 percent for an alloy containing 6 percent aluminium, while the optimum temperature of the annealing for recrystallization (for the duration of 2 days) rise from 880°C for electrolytic iron to 1000°C for a 6% Al alloy. The grain growth is the most excellent in an alloy containing 0.53 percent aluminium (the maximum length of grain being 16 cm) and the most inferior in an alloy containing 2.47 percent aluminium (the maximum length of grain being 6 cm). As the reagent for macro-etching, concentrated nitric acid plus a little quantity of boiling water is suitable for pure iron and alloys containing small content of aluminium, while concentrated hydrochloric acid is adequate for alloys containing more than 2.5 percent aluminium. Dilute nitric acid may be used conveniently for cutting crystals by etching, regardless of the aluminium content. It was confirmed that a polycrystalline layer consisting of one layer of minute grains as existed before the annealing for recrystallization remained on the surface of iron-aluminium single crystals thus prepared.View full abstractDownload PDF (893K) -
Tomo-o Satô, Hideo Kaneko1952 Volume 16 Issue 6 Pages 309-312
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe electrical conductivity of molten selenium containing some doping and anti-doping elements was measured and the following results were obtained.
(1) In the present work, chlorine, bromine and iodine were used as doping reagent. The electrical conductivity of molten selenium containing these halogen elements increases exponentially with the temperature. It increases also exponentially with the chlorine content, but proportionally with the amount of bromine or iodine.
(2) The addition of some anti-doping elements, such as Hg, Te, S and P, gives little effect on the conductivity of molten selenium. However, they diminish the doping action of halogen element, so we can say that they give injurious effect on the rectifying character of selenium.View full abstractDownload PDF (548K) -
S. Nagasaki, E. Fujita1952 Volume 16 Issue 6 Pages 313-317
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe specific heats of Pb-Cd, Bi-Cd and Sn-Bi alloys with various compositions were measured continuously from the solid states to the liquid states. From these measurements, the phase diagrams and energy of fusion, energy of change of state in solid phase and entropy of fusion, energy of change of state in solid phase and entropy of fusion vs. composition curves were obtained, and using these results the theory of phase diagram proposed by Takagi and Nagasaki were examined and developed.
What the theory had deduced and predicted were confirmed by the above observations in most cases, and some anomalies appeared in the observations could be explicated by the ameliorated theories. In Part I, the positions of the eutectic points of Pb-Cd and Bi-Cd systems were discussed. They were situated on the compositions nearer to the components which had the higher melting points (in atomic concentration). This situation contradicted what were expected from the above theory. But this difficult point could be interpreted by considering the very different entropies of fusion (of both components of the alloy).
From the observations some quantities manifested in the theory of binary alloy were obtained. They will be mentioned collectively in Part II.View full abstractDownload PDF (711K) -
S. Nagasaki, E. Fujita1952 Volume 16 Issue 6 Pages 317-321
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn Part I, phase diagrams and energy and entropy of change of states vs. composition curves of Pb-Cd and Bi-Cd systems obtained from the specific heat measurements and the theory of phase diagram proposed by Takagi and Nagasaki were given. In particular, the positions of the eutectic points on the phase diagrams of the above systems were discussed.
In Part II, together with the results on Sn-Bi system, the energy and entropy of fusion or solution of alloys were investigated synthetically. Two important phenomena discussed in this part are the energy of solution of Bi atoms into Sn solid and anomalous liquid states of metals and alloys.
In the study of the former, the quantity containing the mutual potential of Bi and Sn atoms was estimated and solubility limit of α solid solution of Sn was investigated. In the discussion of the latter, the existence of anomalous liquid states of Bi, Sn and their alloys was suggested.View full abstractDownload PDF (776K) -
Tadashi Kawasaki, Gunji Shinoda1952 Volume 16 Issue 6 Pages 322-324
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe recovering process, caused by annealing, of hardness and magnetism of plastically deformed soft steel containing 0.060∼0.090% C were investigated. The magnetic properties of specimen except for the strain sensitivity showed the same results as our last reports. The fact that the strain sensitivity at this experiment shows an abnormal increase at the state annealed at about 700° appears to imply that the quantities of carbon in the specimen are so little that its effect is masked by the other impurities.
The magnetization curve decreases its slope by a plastic deformation and is restored by annealing. When an external tension σc was applid to the specimen annealed at 100∼300° after plastic elongation and also to the normal one, both of them show the same magnetization curve. And when the action of external tension σc was given to the specimen annealed at temperatures between 400∼700°, all the magnetization curves have coincided with one another. The above two typical curves had more steep slopes than that of the normal state. Here σc denotes the abcissa of a maximum point in the B-σ curve at each state.
These results were independent of carbon contents of the specimen and degree of cold-working.View full abstractDownload PDF (487K) -
Taro Ueda, Masao Tanaka1952 Volume 16 Issue 6 Pages 325-328
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the first report the relations between the rotary bending fatigue phenomena and magnetic properties of annealed carbon steels were investigated. In this report the relations of 0.8% C steel wires with various heat-treatments were studied when the test specimens were loaded with the repeated twisting stresses by means of the vertical type twisting machine. The method of research was the same as in the first report. The changes of differential hysteresis loops between the test- and standard specimen due to fatigue were measured by cathode-ray oscillograph.
The experimental results are as follows: when the given repeated twisting stresses were under the fatigue limit, the changes of differential loops were slight, but if they were above the fatigue limit the differential loops changed greatly. And that of the heat treated wires changed gradually or rapidly with the increase of the number of cycles of repeated twisting stress, but that of the cold drawn wires did not change until a certain number of cycles was increased and after that changed greatly. But in either case they changed in the direction to make the area of hysteresis loop of test specimen decrease. These results show the same tendency as one of the rotary bending fatigues.View full abstractDownload PDF (674K) -
K. Monma, S. Uemura, M. Hirata1952 Volume 16 Issue 6 Pages 328-333
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSMany results were reported on the isothermal transformation of steels, but hitherto it was not throughly explained whether any age change had occurred in austenite during incubation period or not.
The authors studied this problems in the cases of high speed steel and some other special steels. As for the method of research, they measured isothermal aging change of electrical resistance in austenite during incubation period, simultaneously confirming magnetically the occurrence of γ→α transformation. And the following results were obtained: (1) At the temperature range of troostite formation, the suppressed austenite which was in incubation period, underwent obvious resistivity decrease by isothermal aging. (2) This decreasing of resistivity was caused by the precipitation of carbide from austenite itself. (3) And the carbon impoverishment of austenite accompanied with carbide precipitation decreased the stability of austenite, so the γ→α transformation came to occur at last. (4) At the intermediate zone of Ar′ and Ar″, the speed of carbide precipitation became very slow, so the time-resistivity curve showed almost no change, which means that the austenite did not become unstable. This is the reason why the γ→α transformation can not be observed virtually in this temperature zone. (5) At the range of Ar″, the isothermal γ→martensite transformation took place gradually, and the transformation accompanied the obvious increase of resistivity.View full abstractDownload PDF (898K) -
Etsujiro Yajima1952 Volume 16 Issue 6 Pages 333-337
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWhen a metal diffuses into another metal, its diffusion constant is invariable at a constant temperature and its value is independent of the diffusing time. However, generally in the experiments of metal diffusion, the constant decreases with the prolongation of the time. It is due to the concentration of diffused metal. In the case of Al diffusion into steel, C content of the steel increases gradually and it causes the decreasing of the diffusion constant. The present author investigated the effect of C content and heating time on the Al diffusion into steels.View full abstractDownload PDF (955K) -
Sôsuke Uchida1952 Volume 16 Issue 6 Pages 338-342
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of the reaction on the steels in carburizing atmosphere mingled with H2S, the atmosphere being produced by the combustion of charcoal with dry or wet air, was researched at various conditions, and following results were obtained:
(1) The attacking of H2S on steels is reduced with the increase of carbon content. (2) The attacking of H2S on steels in atmosphere of CO-N2-H2S is more violent than CO-H2-CH4-N2-H2S. (3) There are some tolerant limits of attacking of Fe by H2S in the atmospheres of CO-N2-H2S or CO-H2-N2-H2S at equilibrium state. (4) There is some excess of Fe in scale of FeS formed on the surfase of steels. From this phenomenon, it is concluded that Fe diffuse in scale toward the surface to react with H2S (5). The carburizing force of such gases decreases with the formation of FeS particle on the surface of steels.View full abstractDownload PDF (921K) -
Masayoshi Tagaya, Imao Tamura1952 Volume 16 Issue 6 Pages 342-346
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSBasing upon the theoritical standpoint described in the 3rd report, the quenching oils were considered chemically and experimented pertinently by present writers.
The results are as follows: For the quenching oil it is desired that the characteristic temperature is higher and the beginning temperature of convection stage is lower because the beginning temperature of convection stage of oil is too high generally. The characteristic temperature of oil consisting of the polar molecules like fatty acid is higher than that of oil consisting of the non-polar molecules like hydro-carbon. For the fatty oil, the larger the molecular weight is, the higher the characteristic temperature and the beginning temperature of convection stage become. When the fatty oil includes the unsaponifiable matters, these two temperatures are lower, which is undesirable, but when the fatty oil has no unsaponifiable matters, the smaller the saponification value is, the larger the molecular weight is, and hence, the higher the characteristic temperature becomes. When the iodine value of fatty oil is large, these two temperatures are a little high. When the fatty oil includes large amount of free fatty acids and, hence, its acid value is high, these two temperatures are lower. When molecules in any oil have a tendency for condensation or polymerization with each other and growing to large molecules, the cooling ability of such a oil is fairly greet.View full abstractDownload PDF (823K) -
Masazô Okamoto, Renpei Yoda1952 Volume 16 Issue 6 Pages 347-351
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSSome chemical and physical changes of molten irons by holding it at 1350∼1400° after treated at 1400° with 0.9% Mg in the from of Mg-Si-Cu-Fe-Al alloy containing 20% Mg were examined by using cast specimens in dry sand mould 14 mm in diameter. Irons treated with the magnesium alloy with chlorides, or with fluorides, or with oxides, were also experimentally discussed.
The spheroidization of graphite was accompanied by the alloying of magnesium as well as deoxidation, desulphurization and decarburization. The disintegration of the spheroidal form was accompanied by resulphurization and recarburization from the slag into the iron. At the maximum of recarburization, the effect of magnesium was almost lost and the microstructure became eutectic with ferrite.
With the longer holding time, decarburization was again seen due to the oxidation of the molten iron and the microstructure became flaky graphite with pearlite. When chlorides, fluorides or oxides were used with the magnesium alloy, the spheroidizing effects decreased.
The slag formed instantly at the magnesium-addition was simillar to the calcium-carbide slag formed during the reducing period in Héroult electric furnace except that magnesium in the former was acting as a substitute for calcium in the latter. Accordingly, the adequate molten iron which easily caused the spheroidization of graphite by magnesium-addition must, at least, be such iron as the magnesium-carbide slag haveing strong reducing action which may easily be formed.View full abstractDownload PDF (1220K) -
Hikozô Endô, Akira Itagaki1952 Volume 16 Issue 6 Pages 352-354
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe immersion corrosion test were carried out on five kinds of austenitic stainless steels. The specimens were alloys of 23% Cr-20% Ni-1.5% Cu-1.5% Si-0.5% Mn, 23% Cr-20% Ni-2% Si-0.5% Mn, 23% Cr-20% Ni-3% Mo-3% Cu-0.5% Mn (clumin M3MC), 20% Cr-23% Ni-1.4% Mo-1.4% Cu-3% Si-0.5% Mn and 23% Cr-20% Ni-3% Mo-3% Cu-2% Si-0.5Mn. The corrosives were aqueous solutions of HCl, H2SO4, HNO3, CH3COOH, (COOH)2, HCOOH, Al2(SO4)3 Ca(OCl)2 and FeCl3 at 27°C and boiling aqueous solutions of HCl, H2SO4 and mixture of H2SO4 and HNO3.
Results are as follows. (i) Alloys of 20% Cr-23% Ni-1.4% Mo-1.4% Cu-3% Si-0.5% Mn, 23% Cr-20% Ni-3% Mo-3% Cu-0.5% Mn had good acid-resistivities against HCl at 27°C temperature. (ii) All alloys were not been attacked at all in H2SO4, HNO3, CH3COOH, (COOH)2, HCOOH and aqueous solutions of Al2(SO4)3 and Ca(OCl)2 at a constant temperature. (iii) Alloys of 23% Cr-20% Ni-3% Mo-3% Cu-2% Si-0.5% Mn and 23% Cr-20% Ni-3% Mo-3% Cu-0.5% Mn had good acid-resistivities against HCl at boiling points. (iv) Alloys of 23% Cr-20% Ni-3% Mo-3% Cu-0.5% Mn and 20% Cr-23% Ni-1.4% Mo-1.4% Cu-3% Si-0.5% Mn and 23% Cr-20% Ni-3% Mo-3% Cu-2% Si-0.5% Mn were not attacked at all in mixture of H2SO4 and HNO3 at boiling points.View full abstractDownload PDF (509K) -
Eiichi Hata1952 Volume 16 Issue 6 Pages 355-358
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAluminum slabs of zommercial purity were hot rolled at various temperatures. They were cold rolled and then annealed. Finer grain size was obtained when they were hot rolled above 500°. Addition of Fe and Si refined grains of annealed sheet, although Fe was more effective Grain size of aluminum sheet of commercial purity became larger with increasing Mn content. Extremely coarse grain appeared when the sheet was annealed at slow heating rate. In order to fabricate fine grained sheet, Mn content should be carefully controlled.View full abstractDownload PDF (593K)
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