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Volume 30, Issue 12
Displaying 1-20 of 20 articles from this issue
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Ishi Miura, Etsuo Sasaki1966 Volume 30 Issue 12 Pages 1099-1104
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe strength of an aluminum sheet in which very thin and fragmentary layers of aluminum oxide were finely lined was studied. This aluminum sheet was made of piled thin aluminum foils by hot rolling. The creep strength and recrystallization of this aluminum sheet have been published in previous reports. Tensile tests at room temperature and high temperatures, X-ray diffractions and microscopic studies on the aluminum sheet were done in this experiment.
Main results are as follows:
(1) The strength of the aluminum sheet at room temperature is a little higher than that of the about same purity commercial pure aluminum plate and the thickness of aluminum foils which are used as raw materials has no strong bearing on the strength of the aluminum sheet.
(2) At high temperatures, the strength of the aluminum sheet is much higher than that of the commercial pure aluminum and increases as the thickness of aluminum foils used as raw materials becomes thinner.View full abstractDownload PDF (1699K) -
Ishi Miura, Hisao Honma1966 Volume 30 Issue 12 Pages 1104-1109
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn a previous paper, it has been found that when the concentration distribution of silver atoms of the aluminum rich aluminum-silver solid solution is controlled under some rules, the mechanical properties are improved. In this paper, similar experiments on the copper-gold alloy are reported to show the effect of difference of alloy systems. The procedure of experiments is as follows: 237 sheets of copper foil (5 μ thickness) and 12 sheets of gold foil (7 μ thickness) were piled up in the form of Cu 79-Au 6-Cu 79-Au 6-Cu 79 for the hardness test and 250 sheets of copper foil and 24 sheets of gold foil were also piled up in the form of Cu 50-Au 6-Cu 50-Au 6-Cu 50-Au 6-Cu 50-Au 6-Cu 50 for the tensile test, the composites of which were then bonded each other by hot rolling at 500°C. The composites in the form of Cu 50-Au 3-Ag 1-Au 3-Cu 50 (the thickness of silver foils=6 μ) were also prepared to examine the effect of the addition of silver foils. When heated these speciments at 850°C, diffusion was advanced to increase the hardness of the parts of gold foils, and hardness was further increased by aging for 30 min at 300°C. This shows that the copper content in the part of gold foils became higher. The mechanical properties of these heat-treated specimens did not show any pronounced improvement compared with the homogeneous alloy containing a nearly same amount of gold. However, the specimens containing a small quantity of silver foils showed a remarkable increase in tensile strength and elongation.View full abstractDownload PDF (1285K) -
Iwao Muchi, Kenji Tamura, Junichiro Yagi, Akira Moriyama1966 Volume 30 Issue 12 Pages 1109-1114
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to clarify the behaviors of charged burdens and gases in the blast furnace, a new mathematical model of the upper zone of a blast furnace has been developed in this paper.
Considering the rates of reactions reported in the previous work and the heat loss from the peripheral wall, material balances and heat balances are taken around the differential height of beds at an arbitrary position in the furnace and the fundamental equations are obtained as Eq. (1)∼(9).
Applying the method of Runge-Kutta-Gill to the numerical calculations, these fundamental equations can be solved by use of a digital computer.
Procedures of estimation of temperature, composition and volume rate of flow of gas and temperature of cokes or molten materials at the tuyere level have also been proposed, and these calculations can be developed apart from the fundamental equations mentioned above.View full abstractDownload PDF (1793K) -
Iwao Muchi, Kenji Tamura, Junichiro Yagi, Akira Moriyama1966 Volume 30 Issue 12 Pages 1115-1120
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSStatic characteristics of the upper zone of blast furnaces have been studied theoretically.
Results obtained by means of a digital computer have been compared with the experimental results reported by others. As a consequence it has been found that our mathematical model is effective in considerable measure to guess the conditions of materials in blast furnaces theoretically.
Longitudinal distributions of average temperatures of gases and burdens, fractional reductions of ores, and volume rates of flow, compositions and densities of gases, which have been determined from the mathematical model, are shown in Figs. 2, 3 and 4 for the actual operating conditions of three furnaces.View full abstractDownload PDF (1528K) -
L’essai de Frottement Intérieur en Torsion sur les Eprouvettes de l’Al et du Zn Purs MonocristallinsHiroyasu Funakubo, Nobuhiko Iwao1966 Volume 30 Issue 12 Pages 1121-1126
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSL’influence de la contrainte de cisaillement max. appliquée sur les valeurs de frottement intérieur est proportionnelle à la valeure de la composante de cette contrainte sur la direction de glissement située dans le plan de glissement le plus proche à la surface de cisaillement. (valeur maximum de la cission réduite.)
On peut difinir le coefficient de cette composante et tracer sur les diagrammes stéréographiques la répartition de ce coefficient dans le cas où l’orientation de la surface de l’éprouvette est (100), (110) et (111) respectivement sur les cristaux de f.c.c. et de b.c.c.
Ces diagrammes théoriques coincide bien avec les résultats expérimentaux et aussi avec les résultats analytiques et expérimentaux des essais d’ emboutissage et de valeur du coefficient de Lankford effectués sur le Fer et l’Al purs en tôle mince monocristallin.View full abstractDownload PDF (1638K) -
Hisasuke Takeuchi, Tadatoshi Toda1966 Volume 30 Issue 12 Pages 1126-1130
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAn experimental method for the measurement of repressibility of sintered iron is proposed. The device employs the pressing-load-contraction recording apparatus while placing the specimen in the cylindrical die. The influence of the presintering treatment on the repressibility of the sintered Höganäs iron powder was studied, with the following results:
(1) The specimen density increased corresponding to the repressing load, being independent of the presintering temperatures between 800°C and 1200°C. On the other hand, the sintered iron specimens which were prepared by the repeated sintering and repressing to have the same density have the following mechanical properties: (a) The maximum tensile strength is obtained at a sintering temperature of 1200°C, independent of the presintering temperature. (b) In the case of the repeated sintering of the iron compact at a same temperature, the lower the sintering temperature, the lower the tensile strength value in the sintered state; in particular, the elongation of the sintered iron has the lowest value at the sintering temperatures below 850°C. (c) The tensile strength of the specimens in the repressed state becomes higher with increasing sintering temperature.
(2) The effect of the lubricant on the density increase by repressing was confirmed from the pressing-load-contraction characteristics.View full abstractDownload PDF (1413K) -
Masanobu Ohmori, Yoshitoyo Yoshinaga1966 Volume 30 Issue 12 Pages 1131-1137
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSBy use of two torsion testing machines, i.e. a static machine and a high speed one which was designed and constructed by the present authors, the plastic shearing behaviors of a killed carbon steel with 0.14%C were investigated at the temperatures rauging from −78° to 600°C under the shearing strain rates of 1.1×10−2, 1.1×10−1, 1.4 and 1.4×10 1/sec. The main findings are summarized as follows:
(1) The rise of about 50°C in the blue-brittleness temperature was induced by a ten-fold increase in shearing strain rate, and the temperature range in which the brittleness was observed became wider with strain rate. The effect of the shearing strain rate on the brittleness temperature resembles that of the tensile strain rate.
(2) The shearing yield stress (lower yield stress) at −78°C and room temperature could be expressed well by increasing linear functions against the logarithm of the shearing strain rate. The yield stress has two rate sensitivities; i.e. a smaller sensitivity below the rate of 10−1 1/sec and a larger one beyond it, both sensitivities increasing with lowering of the testing temperature. In contrast with the behaviors at −78°C and room temperature, no sensitivity appeared on the yield stresses at the temperatures from 200° to 400°C, which remained quite constant respectively through the strain rates encountered in the present experiment.
(3) The facts that the maximum shearing stress at −78°C decreased with the strain rate and the stress at room temperature was almost independent of the strain rate resulted from the temperature rise in the test piece with higher speed deformation. The plastic work required to deform the present steel up to the strain at tensile strength in the uni-axial tension test was equal to that to stress it up to the strain of about 0.6 in the shearing deformaion. The shearing stress at this strain showed a similar strain rate sensitivity to that for the tensile strength.
(4) Under the quasi-static deformation, the ratio of the shearing yield stress to the tensile one at the temperature from −78° to 300°C fell around the value of 0.577 which is expected from von Mises’ yield criterion. Under the higher speed deformation, however, the ratio somewhat decreased to approach the value of 0.500 by Tresca’s criterion.View full abstractDownload PDF (1452K) -
Pongun Son, Seiichi Ihara, Masanobu Miyake, Tadao Sano1966 Volume 30 Issue 12 Pages 1137-1140
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe diffusion coefficients of carbon in tantalum has been studied by tracer techniques using C14 over the temperature range of 1450°∼2200°C.
The diffusion coefficients are described by the equation, D=0.012exp(−40.3⁄RT) cm2/sec.
Comparing the above results with the values by Powers et al obtained by the internal friction method at about 350°C, it can be understood that the activation energy for carbon diffusion in tantalum takes constant values of 39∼40 kcal/mol over a wide temperature range of 300°∼2200°C and further that the diffusion of carbon in tantalum is operated by an interstitial mechanism even at a temperature as high as 2200°C.View full abstractDownload PDF (925K) -
Hiroshi Ishizuka, Keizo Onishi1966 Volume 30 Issue 12 Pages 1140-1146
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn a previous report the authors reported that susceptibility to sulfide corrosion cracking in the high strength steel plate had close relation to the mechanical properties. The rolled steel plate having directionality in the mechanical properties, however, the cracking susceptibility of high strength steel plate may have some bearing upon the directionality.
In this report, the authors made investigation on each directionality of cracking susceptibility, hydrogen blistering, and hydrogen absorption with sheet specimens sampled from various directions of the steel plate. The results obtained are as follows:
(1) The high strength steel plate has directionality in sulfide corrosion cracking susceptibility. That is, the specimen sampled parallel to the rolled surface of the plate showed to be more susceptible to sulfide corrosion cracking than the specimen sampled from the thickness direction of the plate.
(2) Hydrogen blisters and hydrogen cracks in the plate by sulfide corrosion appeared only parallel to the rolled direction and not in other directions. It was observed that these cracks were related to non-metallic inclusions which were deformed by hot rolling.
(3) Furthermore, in connection with the above facts, by sulfide corrosion, the steel plate has also directionality in hydrogen absorption. That is, the specimen sampled parallel to the rolled surface of the plate showed a larger amount of hydrogen absorption than the specimen sampled from the thickness direction of the plate.View full abstractDownload PDF (1100K) -
Hiroshi Ishizuka, Keizo Onishi, Takashi Sugiura, Kazuyoshi Nishino1966 Volume 30 Issue 12 Pages 1147-1152
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSTests on sulfide corrosion cracking of weldable high strength structual steels were performed at oil refining plants. The tests were carried out on eight main parts of the oil refining plants, viz., oil storage tank, prefractionator, top and bottom sides of fractionator, stabilizer, stabilizer-receiver, depropanizer-receiver, and vacuum column. The duration of testing was about one year. The results obtained are as follows:
(1) Sulfide corrosion cracking was only observed on the test specimens inserted in the stabilizer-reciver, and specimens in other processing units in the plant were found to be unaffected. It was observed that the conditions causing the sulfide corrosion cracking might be attributed to the environment being (a) liquid phase, (b) rich in H2O, (c) rich in active sulfide such as H2S, and (d) subjecting temperature.
(2) Types of cracks observed on the test pieces were corrosion cracking on the surfaces, hydrogen blister, and hydrogen crack.
(3) The scales removed from the cracked specimen surface were examined and as a result, kansite (Fe9S8) that is closely related to sulfide corrosion cracking was detected by X-ray diffraction. Residual hydrogen in the specimen was rich compared with that in other parts of plants.
(4) The corrosion rate of tested materials varied considerably by individual cases, but did not vary to any extent by different heats of steel.View full abstractDownload PDF (1431K) -
Katsuhisa Sugimoto, Yoshinobu Sawada, Susumu Morioka1966 Volume 30 Issue 12 Pages 1153-1158
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of NO3− or NO2− ions on the potentiostatic polarization of 99.99%Al in the neutral aqueous solution of NaCl have been investigated. The results obtaind are summarized as follows:
(1) Pitting corrosion of aluminum in 0.5 N-NaCl solution is not inhibited completely by the addition of 0.5 N NO3− or NO2− ions.
(2) An abnormal reduction peak is observed on the cathodic polarization curve of 99.99%Al in the solution containing NO3− or NO2− ions at the potential near −1.3 V (vs. S.C.E.), but no peak is observed on the curves of other pure metals and alloys, such as 99.49%Al, Cu, Fe, Ti, Zn, Pt, Cu-Hg and Zn-Hg. This reduction peak which is charactaristic of 99.99%Al in these solutions is due to both the existance of colloidal films on the surface and the greater hydrogen overvoltage of this metal.View full abstractDownload PDF (1976K) -
Masao Ibaraki, Taira Okamoto, Katsuhiko Kishitake1966 Volume 30 Issue 12 Pages 1159-1163
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe growth conditions and the effect of solute elements for the columnar-equiaxed transition during solidification of castings of binary alloys have been investigated using aluminum base alloys whose equillibrium distribution coefficient, k0 is less than unity. The transition have been accounted for on the basis of the mechanism of nucleation in the constitutionally supercooled region. The value of GL⁄R1⁄2, where GL is the temperature gradient in liquid ahead of growing dendrite tips and R is the freezing rate, at the position of the transition is proportional to the solute content, C0. When the growth condition is constant, the solute content required for the transition is inversely proportional to a parameter, −m(1−k0), as the constitutional character of alloys, where m is the liquidus slope. Accordingly, when the following relation is satisfied, the columnar-equiaxed transition occurs: −mC0(1−k0)R1⁄2⁄GL≥B, where B is a constant.View full abstractDownload PDF (1592K) -
Yasuya Ohmori1966 Volume 30 Issue 12 Pages 1164-1167
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of small Nb additions upon the recrystallization of austenite in a mild steel immediately after hot working has been investigated. The samples solution-treated at 1250°C were hot-rolled and subsequently held for various time at the working temperature and quenched in water. After tempering at 550°C, austenite grain boundaries in tempered martensite were revealed by the saturated solution of picric acid containing a small amount of sodium benzen sulfonate.
The activation energies for recrystallizations of austenite in a mild steel without Nb were 99 kcal/mol for 30 pct reduction and 72 kcal/mol for 50 pct reduction respectively. The small Nb additions heavily reduced the recrystallization of austenite and varied the temperature dependence of recrystallization time, so the constant activation energy could not be obtained for a Nb-treated steel. The mechanism for this effect was presumed to be attributable to the precipitation of Nb-carbonitride in austenite.View full abstractDownload PDF (1466K) -
Tooru Furukawa, Osamu Miyakawa1966 Volume 30 Issue 12 Pages 1167-1172
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt is generally believed that the age hardening in 17-7PH stainless steel is accomplished by the precipitation of an ordered Ni-Al compound. However, the details are unknown, mainly because the microstructure is complex and the precipitate cannot be detected or identified with certainty. As a fundamental study of the age hardening mechanism in this steel, it was investigated whether or not the ordered Ni-Al compound was precipitated by aging. The results obtained are summarized as follows:
(1) The decrease in dilatation diagram was observed at 440° and 570°C on heating 17-7PH stainless steel in martensite matrix. Whereas, in the case of 17 Cr-7 Ni stainless steel (no Al), the decrease at about 440°C was not observed. The former seems to be caused by the reaction due to the presence of Al, the latter by the transformation of martensite to austenite. (2) The changes in dilatation diagram, specific electrical resistance, B-H diagram, lattice constant, and electron micrograph, all suggest that precipitation take place on aging. One of the precipitates in the overaged specimens turned out to be a CsCl type structure with a lattice constant of 2.88 Å, viz. NiAl, from X-ray and electron diffraction measurements and chemical analysis.View full abstractDownload PDF (2467K) -
Sakae Takeuchi, Toshio Honma, Susumu Ikeda1966 Volume 30 Issue 12 Pages 1173-1177
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe temperature-pressure-concentration relationships of the hydrogen-titanium system have been studied at 900°∼1500°C using a modified volumetric method, and the solubilities of hydrogen at 1 to 760 mm of mercury have been established. The results can be expressed as PH2=kc2exp(Q⁄RT), where the values of the heat of solution of molecular hydrogen in titanium Q and constant k have been obtained as −25.84×103 cal/mol and 26.01×103 mmHg/(at%)2, respectively, from the experimental data. The free energy-mole fraction of hydrogen curves for β-solutions have been plotted for a number of temperatures, and the results have been compared with the McQuillan’s results obtained at temperatures below 950°C.View full abstractDownload PDF (1091K) -
Surface Observations of Precipitates in Commercially Pure Copper Compressed at Elevated TemperaturesSadatoshi Inada, Koichi Uesaki1966 Volume 30 Issue 12 Pages 1177-1182
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSBehaviors of precipitates around inclusions and along grain boundaries on the free surface of phosphor-deoxidized copper compressed at elevated temperatures between 650° and 770°C have been reported in the previous paper. In the present work, behaviors of precipitates in commercially pure copper compressed at elevated temperatures between 650° and 830°C are studied, using furnace-cooled and water-cooled specimens.
The results are as follows:
(1) Precipitates around inclusions as observed in phosphor-deoxidized copper are not observed in the present specimens.
(2) Precipitates along grain boundaries are not observed in the specimens which are not compressed, but they are observed in the compressed specimens along the direction not parallel to the direction of compression and they cause the crack formation. The silicon content which is found to be very low by chemical analysis segregates from the matrix into the grain boundaries and precipitates. It appeares that silicon acts on the crack formation. In the furnace-cooled specimens, there are some differences in cracking behaviors between the specimens which are compressed constantly and rapidly. The results mentioned above are similar to those observed in phosphor-deoxidized copper.
(3) In phosphor-deoxidized copper, silicon and silver segregate along grain boundaries, but in commercially pure copper, silicon and zinc segregate along grain boundaries.View full abstractDownload PDF (2261K) -
Eiji Takahashi1966 Volume 30 Issue 12 Pages 1183-1187
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to study the influence of carbon plus nitrogen on the flow stress of iron, strain rate cycling tests have been performed during the tensile deformation of polycrystalline iron specimens with four different carbon plus nitrogen contents, 0.005, 0.010, 0.013 and 0.034 wt%, in the temperature range 203°∼373°K. The effective stress and the parameter m* in the Johnston-Gilman velocity-stress relationship \dotε∝nbσ*m* on these iron specimens have been determined from the results. The parameter m* increases with the increase of carbon plus nitrogen in solution and the effective stress tends to increase with the increase of carbon plus nitrogen in solution. Therefore, it is supposed that carbon and nitrogen serve as a resistance against moving dislocations. The coefficient of work hardening is scarecely influenced by carbon plus nitrogen.View full abstractDownload PDF (1193K) -
Masao Kondo, Hiroshi Nagata, Yuzuru Nakamoto1966 Volume 30 Issue 12 Pages 1187-1191
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSFor the purpose of rapid carburizing of steel, we studied induction high temperature carburizing for Ni-Cr-Mo case hardening steel SNCM 23, in the atmosphere of propane-butane gas (JIS LPG No. 3) only or in the atmosphere diluted by nitrogen, and examined the influence of heating temperature (950°∼1300°C), holding time (below 90 min), gas flow (0.5∼1.51/min), dilute ratio of gas (propane-butane gas: nitrogen gas……1:4, 1:8, 1:16) on the rate of carburizing and microstructure.
The results were as follows:
(1) When the atmosphere was propane-butane gas only, the soot deposited at the surface of the specimen, and with prolongation in carburizing time, carburizing was injured. Under this condition, the rate of carburizing was a little larger than that obtained by the conventional gas carburizing at the same temperature.
(2) When the atmosphere was diluted by nitrogen gas, the soot did not deposit and for the dilute ratio adopted in this experiment, the rate of carburizing was about 1.4 times larger than that obtained in the propane-butane gas only at the same temperature. Under this condition, the depth of the carburized layer was 2.0 mm at 1200°C for 30 min or 1.8 mm at 1300°C for 10 min.
(3) The surface of the carburized layer had a carbon content which was rich enough to obtain the hardness above Hv 700, and the carbon content distribution curve became more gentle with increase in heating temperature.
(4) The flow rate or the dilute ratio of gas did not affect the rate of carburizing so far as this experiment was concerned.
(5) No grain growth was observed at the core of the specimen carburized at temperatures 1000°∼1300°C for only 30 min. For the carburized layer and core of the specimen, a normal microstructure and gentle hardness distribution curve were obtained by quenching and tempering.View full abstractDownload PDF (1071K) -
Yukiaki Hara1966 Volume 30 Issue 12 Pages 1192-1193
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSDownload PDF (206K) -
1966 Volume 30 Issue 12 Pages 1193
Published: 1966
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSPlease see pdf. Wrong:0.01%, (f) melted in…, (i) …conatining… Right:0.05%, (f) melted for…, (i) …containing…View full abstractDownload PDF (18K)
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