All issues
Volume 24, Issue 11
Displaying 1-20 of 20 articles from this issue
- |<
- <
- 1
- >
- >|
-
Masataka Sugiyama, Hisashi Suzuki1960 Volume 24 Issue 11 Pages 689-692
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe vacuum-sintering of TiC-Ni cermets was studied for the purpose of obtaining basic informations on the sintering technique of TiC-base cermets. Under a fixed condition of ball-milling, some properties such as the strength, the hardness, the density, the microstructure, the carbide grain size etc. of the cermets were described as a function of metal binder contents, pressing pressures and sintering conditions and the correlations between the properties were also made clear.View full abstractDownload PDF (830K) -
Kichinosuke Hirokawa1960 Volume 24 Issue 11 Pages 692-696
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to determine alloying elements in some special steels, a calibration curve method, in which the metal of sample holder was used as the compensative reference, was tried. This method was recognized to be simpler and more suitable to rapid analysis than other methods. Then the influence of other coexisting elements on the results of tests using the calibration curves of binary system, and some others topics were discussed.View full abstractDownload PDF (720K) -
Kichinosuke Hirokawa1960 Volume 24 Issue 11 Pages 696-699
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA semiquantitative method to estimate the influence of the various elements in the samples was tried. This method was based on the application of the approximate equation, Iae=\dfracKa·WaΣbWb(μb⁄ρb), which was introduced by R. M. Brissey, C. Sautier and others. Using this equation the influence of the coexisting elements in some alloys were estimated semiquantitatively.View full abstractDownload PDF (516K) -
Akira Moriyama, Jyoichiro Moriyama, Isao Kushima1960 Volume 24 Issue 11 Pages 699-703
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe surface behaviors of the iron oxides in loose powder mass were studied. The results from the following three experiments are described: (i) Measurement of the specific surface area of iron oxides produced by the thermal decomposition of iron salts, (ii) the changes of the specific surface area of iron oxide powder by heating at constant temperatures, (iii) the densification of iron oxides. All the experiments were conducted under atmospheric pressure. By heating Fe (III) salts, the surface area of oxides suffered regular changes, but in the case of Fe (II) salts, random changes of the surface area were observed. The rate of contraction of the surface area of iron oxides by heating can be described by the next formula; −dVt⁄dt=kVt, and its activation energy is about 10 kcal/gmole.View full abstractDownload PDF (670K) -
Eiichi Kato1960 Volume 24 Issue 11 Pages 703-707
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSSmall rectangular specimens (6×6×50 mm) were chill-cast in a copper mould from molten Fe-C-Si alloys (C 0.04∼4.43%, Si 0.14∼3.65%) and molten commercial cast iron. The rate of evolution of hydrogen at room temperature from these specimens were measured by placing them in test tubes filled with mercury or in evacuated tubes. In general, the specimens containing higher carbon and silicon had considerably slower rate of evolution. The hydrogen evolution from the specimens with high carbon and silicon content was too slow to be measured by the test tubes filled with mercury, but all the specimens tested in the evacuated tubes evolved hydrogen. A 95% value period which is the time required for evolution of 5% of initially contained hydrogen was used to indicate the rate of hydrogen evolution. The 95% value period for steel, malleable cast iron and ordinary cast iron were 0.6∼2.2 hrs, 22∼70 hrs and 70∼167 hrs, respectively. A drop of temperature was effective in slowing hydrogen evolution, and the 95% value period of the specimen in ice was lengthened to about twice of that of the specimen at room temperature.View full abstractDownload PDF (636K) -
Kiyoshi Tamura1960 Volume 24 Issue 11 Pages 707-710
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSSome basic properties of TiSi2 as a refractory hard material have been investigated. TiSi2 powder was prepared by arc melting in an argon atmosphere of pure titanium and silicon mixture and subsequent crushinged by ball-mill. This powder was then hot-pressed in vaccum. The specimens obtained were subjected to various tests, the results of which are summarized as follows: (1) The optimum temperature in hot-pressing of TiSi2 was 1380°C. The density attained 99.8% of the theoretical value. (2) The oxidation resistance at 1100°C was 0.0005 g/cm2/day. (3) In general, the hardness in hot state decreases with rising temperature. For instance, it was 230 (HV) at 800°C. (4) The corrosion resistance was is good against hydrochloric acid and sulpheric acid, while it was not so good against nitric acid. (5) The thermal schock resistance of TiSi2 was poor. (6) TiSi2 was well wetted by Fe, Ni, Co. (7) Ag does not wet TiSi2.View full abstractDownload PDF (676K) -
Koichi Kawamura1960 Volume 24 Issue 11 Pages 710-714
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAqueous solutions of hydrogen peroxide, acids and other additional reagents were used for descaling, chemical polishing and etching of several metals and alloys. Measurements were carried out on stainless steels, heat-resisting steels, plain carbon steels, and many alloy of copper, titanium, nickel, magnesium, aluminium or lead. Metals and their oxides dissolved in the aqueous solutions of hydrogen peroxide containing the additional components of adequate quantity more easily than in ordinary acids. The most suitable proportion of the components of solutions and the optimum experimental conditions, with which excellent results of descaling, chemical etching and polishing can be realized, were determined.View full abstractDownload PDF (924K) -
Tatsuo Maekawa, Michio Mizuta, Katsumi Ishihara1960 Volume 24 Issue 11 Pages 714-718
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSEddy current testing is one of the most effective nondestructive test methods in the fields of thin-tube inspection and the theoretical foundation on its nature is already analysed in detail. However, published practical data on the testing are comparatively few. Therefore, the changes of the current flowing in a annular coil (7 KC) on a tensile-deformed thin tube (initial tube dimension; O.D. 8.56 mm, I.D. 7.50 mm) of AISI-304 type austenitic stainless steels were investigated. The main results obtained were as follows: (1) The current change (the only phase component) caused by tensile deformation of the tube specimen increased in accordance with the increase of unstability of the austenitic phase of the initial tube. (2) The electrical resistivity and the magnetic property can be considered as factors affecting the current change. The measurement showed that the former change is comparatively small and the latter change is predominant. This means that the measured change is caused by a precipitation of ferrite phase in the austenite phase by deformation. (3) The current change is affected by heat-treatment before deformation. Generally speaking, the change of annealed specimen is larger than that of solutionized specimen (in annealed specimen it became to the maximum at the annealing temperature of ca. 650°C). (4) Recovery of the current change takes place at the temperature of 400∼650°C. The activation energy of recovery decreases continuously with increasing gross recovery.View full abstractDownload PDF (818K) -
Kamihiko Itsuki, Fukunosuke Suzuki, Kazuo Nishino1960 Volume 24 Issue 11 Pages 718-722
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA method of spectrographic determination of arsenic, antimony, tellurium, nickel, bismuth, aluminum, lead, tin and iron in crude copper was devised. The sample was dissolved in acid, heated on sand-bath and converted into cupric oxide. This was mixed with 1/5 part of graphite powder, charged into the cavity of a graphite electrode and was excited under the following conditions with Vari-Source. For the determination of arsenic, antimony and tellurium, D.C.-Arc, current: 5 A, arc gap: 2 mm, exposure: 50 sec. For the determination of arsenic, antimony, bismuth, nickel, aluminum, lead, iron and tin, Uni-Arc, L2: 40 mH, C2: 0.0025 μF, R2: 1 Ω, current: 5 A, arc-gap: 2 mm, exposure: 60 sec. The reproducibility of the recommended methods is 6∼10%, as expressed by coefficient of variation, for the determination of 0.003∼0.03% antimony, nickel, bismuth and aluminum; 8∼16% for the determination of 0.002∼0.1% arsenic, lead and tellurium; and 18∼25% for the determination of about 0.03% iron and tin. The analytical results obtained by the recommended method agreed with those obtained by other methods except with iron and tin. Special precautions must be taken in the sample preparation for the determination of iron and tin.View full abstractDownload PDF (722K) -
Renpei Yoda, Heitaro Yoshida, Sennosuke Takahashi1960 Volume 24 Issue 11 Pages 723-727
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSNimonic type heat-resisting alloys have increased Co, Mo and Al+Ti content for the improvement of high temperature properties, at the expense of the forgeability. The principal cause for the loss of forgeability is due to the increase of Al+Ti content. Therefore, in the present paper, the effect of Al+Ti content on the forgeability of Nimonic-100 type alloys was investigated, and also next place, the age-hardening property, the oxidation resisting property and the metallographical structure of the alloys were examined. The results obtained were as follows: (1) Under the present experimental condition, the limit of possible hot-working of Nimonic 100 type alloys is on the line linking a point of about 4.5%Al and 0%Ti with a point of 0%Al and about 5%Ti, when the Al content is choosen as the coordinate and Ti as the abscissa. (2) The Vickers-hardness on the above boundary line is about 230∼260 in the case of solution-treated alloys. (3) The deformation resistance at 1100°C on the line is about 40∼45 kg/mm2. (4) The time required to reach maximum hardness in age-hardening at 900°C of the alloys is about 8∼30 hrs, and the amount of the softening is small in aging below 500 hrs. (5) From the result of age hardening test of the specimens containing a definite amount of Al+Ti, it was found that Ti contributed in age-hardening more than Al. (6) The constitutional diagram of the alloys solution-treated at 1150°C for 15 hrs was determined. (7) Al is effective for the improvement of oxidation resistance, but Ti has a detrimental effect on the contrary.View full abstractDownload PDF (953K) -
Kingo Kiyonaga, Toshio Okuno1960 Volume 24 Issue 11 Pages 727-731
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe gas-carburizing capacity of some case-hardened steels in common use (JIS-S 15 CK, SCM22 SNC 22, SNCM 21 and SNCM 23) was studied, using a batch-type gas furnace. Namely, the effect of dew point, carburizing temperature and holding time on the C distribution curve was determined by means of a turning method. From these results, the behavior of surface C content, the case depth and the diffusion coefficient of C due to various carburizing conditions was clarified concerning these kinds of steels. The main results obtained were as follows: (1) Cr-Mo steel showed a higher surface C content than Ni-Cr or Ni-Cr-Mo steels under the same gas conditions, and especially a much increased surface C content was observed in the former due to production of free cementite when the C potential of reaction gas rose over thes aturation content of C in austenite. On the other hand Ni-containing steels did not show such a tendency. (2) The case depth varied with changes in carburizing temperature, time, dew point and kinds of steels, but it will be noteworthy that the effect of dew point was particularly remarkable. (3) The diffusion coefficient of C at 925°C of these steels was 1300∼1700×10−5 cm2/day; within this range, that of Ni-containing steel was larger than that of Cr-Mo steel. (4) As the conclusion, the gas-carburizing capacity of case hardened steels are determined by C diffusivity and the behavior of surface C content from the view-point of kind of steels. That is, the steel with a larger C diffusivity and a comparatively high surface C content is effeciently carburized and the case depth becomes larger, under the same gas condition.View full abstractDownload PDF (773K) -
Harunobu Sawada, Akira Masuda, Yoriyasu Atobe, Toshimasa Aoki1960 Volume 24 Issue 11 Pages 732-735
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe phenomenon of disintegration (or self-pulverization) of 50Fe-50Al alloy containing 0∼2% carbon in open air was studied. It was microscopically confirmed that the cracks leading to disintegration originate at the boundaries of Al4C3 grains. Cracks growing at every successive stage were observed. X-ray diffraction analysis showed that the stress stored in cast ingot is released with the progress of disintegration. On the other hand, by determination of the amount and composition of the gas evolved from a sample immersed in water, it seemed that the reaction of Al4C3 with water to produce methane plays an essential role in disintegration. Some observations on disintegration based on these experimental results are presented.View full abstractDownload PDF (816K) -
Norio Sato, Go Okamoto1960 Volume 24 Issue 11 Pages 735-739
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of the concentrations of hydrogen-, nickel- and sulfate-ion were investigated in the potential-independent dissolution of passive nickel in sulfate solution. The observed dissolution current iA decreased with the increase of pH in the acidic region, logiA=k−0.46 pH, and was independent of the concentrations of either nickel ion or sulfate ion. In the alkaline solution, on the other hand iA increased with increasing pH. These results were analysed in terms of the electrochemical kinetics and the following mechanisms were proposed for either region, respectively:
(This article is not displayable. Please see full text pdf.)View full abstractDownload PDF (711K) -
Masataka Sugiyama, Hisashi Suzuki, Akio Hara1960 Volume 24 Issue 11 Pages 740-743
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSMicroscopic studies to obtain correct informations on the mechanism of brittle fracture process of cermets (WC-Co-cemented carbides and TiC-base alloys) were carried out. The preferential cracking of carbide grains in these cermets at low temperature, the effect of strain rate on the carbide cracking, origination of the initial cracks, their progressive growth to fracture, dangerous length of the fracture to break down the specimen and the discrepancy between the mode of fracture at low and at high temperature, etc. were described. The flake graphite precipitate and the chrome carbide aggregates in TiC-base cermets were noticed as possibly dedrimental to their mechanical properties.View full abstractDownload PDF (1158K) -
Tomisaburo Nara, Yoshito Yamada1960 Volume 24 Issue 11 Pages 744-748
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe tensile properties and microscopic structures were investigated with copper wires prepared from zone-refined ingot by 16 passes through the molten zones, by drawing of 99% reduction. The results obtained were as follows: (1) Large recrystallized grains were observed in the refined portions aged at room temperature, but no recrystallization was observed in the impurity-concentrated portions, crude copper, and commercial vacuum-melted copper. (2) According to the progress of recrystallization, remarkable reductions in ultimate tensile strength and micro-Vickers hardness values were also observed in the refined specimens aged at room temperature; these reductions are in clear relations with the decrease in the impurity content resulting from zone melting. (3) It has been found that the half-annealing time of the most refined specimen was much shorter than that of OFHC and almost similar to that of the spectroscopically pure copper (99.999%). Accordingly, the measurement of half annealing time may be one of the valuable methods to estimate the purity of copper.View full abstractDownload PDF (1352K) -
Hiroyasu Mitani, Norihiko Nakanishi1960 Volume 24 Issue 11 Pages 748-751
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWassermann, Obinata and Kurdjumow reported that the β′ martensite is produced from β through β1, i.e. ordered β, on rapid cooling in Cu-Al binary alloys. As it is confirmed that the formation of β1 is not arrested even by water-quenching, it is interesting to find out some microscopic figures about β1 transformed from β, and as it may be supposed that the isothermal transformation of β is affected by the transformation β→β1, the authors have tried to determine the T/T/T-diagram for two kinds of specimens, namely of 11.44 wt% and 12.18 wt%Al contents. As the results of the present experiments, it was found that the process of the formation of β1 had an important part in the T/T/T-diagrams, and the eutectoidal precipitation appeared directly from β1 containing about 12.4 wt%Al at the temperature below Tc, i.e. the critical temperature for the transformation β→β1. It was also observed microscopically that some rosette or granular precipitates and the sheath enveloping α were accompanied by the formation of β1. The probable nature of the decomposition processes of β and β1 has been discussed.View full abstractDownload PDF (948K) -
Hiroyasu Mitani, Norihiko Nakanishi1960 Volume 24 Issue 11 Pages 752-755
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the previous report, the authors tried to obtain the T/T/T-diagrams for two kinds of Cu-Al binary alloys containing 11.44 wt% and 12.18 wt%Al respectively. And it was found that some complex phenomena occurred with the decomposition of the β phase at the temperature below the eutectoid temperature. In consideration of the results of this experiment, the following processes may be deemed reasonable. When Th>Tc, β→α or γ2+E and when Th<Tc, β→β1+α→E+α. Th and Tc stand for the temperature of holding and the critical temperature of β→β1, respectively. It has been shown that the transformation β→β1 preferentially proceeds at the temperature below Tc, and some characteristic structures, the so-called rosettes or granular precipitates and sheaths enveloping α have appeared with the formation of β1. Now, to confirm these phenomena again, the authors have carried out some experiments for obtaining the T/T/T-diagrams for the specimens of 12.49 wt%, near the ideal Cu3Al composition, and of 12.96 wt%Al content. From the present experimental results, it was found that the transformation β→β1 predominantly proceeds at the temperature below Tc causes the alteration of Al concentration, and then the eutectoidal decomposition occurs directly from the β phase of the alloy containing 12.49 wt%Al. Some discussions about the mechanism of the transformation β→β1 in Cu-Al binary alloys are appended.View full abstractDownload PDF (963K) -
1960 Volume 24 Issue 11 Pages 755
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSPlease see pdf. Wrong:[in Japanese] Right:[in Japanese]View full abstractDownload PDF (13K) -
Shigetoshi Takayanagi1960 Volume 24 Issue 11 Pages 756-760
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe surface oxidation of tungsten powder has been studied in the temperature range 150∼400° and at the oxygen pressure ranging from 10 to 400 mmHg, using a vacuum microbalance technique. Tungsten powders are pyropholic above the temperature which is dependent on the particle size, doping, heat treatment and oxygen pressure, etc. Below this temperature, two oxide layers are formed during the oxidation process. The outer layer is porous WO3 and the inner one is a dense, thin oxide film of a certain composition similar to that of the outer. The oxidation rate eventually comes to comply with linear law after a initial stage of film growth which is governed by a parabolic law. The mechanism of this oxidation kinetics is explained by the use of a model of a barrier scale layer.View full abstractDownload PDF (807K) -
Susumu Yoshida, Yukio Ohba, Norio Nagata1960 Volume 24 Issue 11 Pages 760-764
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe authors studied systematically the recrystallization behaviour of pure chromium of 99.9% purity produced by the electrolysis of chromic acid and obtained the following results: (1) The primary recrystallization behaviour of high-purity chromium was observed to follow the wellknown general rules of recrystallization. (2) The minimum amount of working necessary for producing primary recrystallization was about 10% of reduction by rolling. (3) The activation energies for recrystallization were measured as 100 to 112 kcal/mol by isothermal measurements for specimens which were subjected to 73% reduction. (4) Grain growth due to boundary migration was observed during annealing above 1000°C for specimens which were subjected to 6∼9% reduction.View full abstractDownload PDF (1025K)
- |<
- <
- 1
- >
- >|