巻号一覧
44 巻, 11 号
選択された号の論文の17件中1～17を表示しています
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野里 僚一, 井沢 秀雄, 椿野 晴繁1980 年 44 巻 11 号 p. 1203-1210
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーElectrical resistivity was measured on specimens aged at temperatures between 273 and 423 K for various times after quenching from temperatures Tq between 623 and 823 K.
\ oindent(1) Resistivity increases in two stages during isothermal aging below 403±5 K, which is in good agreement with the solvus temperature of G. P. zones, irrespective of Tq value. The precipitation below 403 K is a competitive reaction of (I) growth of G. P. zones and (II) formation of δ″ particles (short-range ordered Al3Li). The first and second stages of resistivity increase are attributed mainly to the reactions (I) and (II) respectively. (2) With the reaction (II), the resistivity decreases initially and then increases, exhibiting a tendency to show no resistivity-peak. This resistivity increase makes a sharp contrast with the occurrence of resistivity-peak associated with the reaction (I). (3) The reaction (I) is retarded while the reaction (II) is accelerated with increasing Tq. The retardation effect of high Tq on the reaction (I) decreases with decreasing prequench heating time at the Tq. These results suggest that the distributions of both vacancy and solute atom (Li) in the solid solution become non-random with increasing heating time at the Tq. (4) The activation energies for the reactions (I) and (II) were estimated respectively to be 67.5±5 and 110±7 kJ/mol, which may be assigned to migration energies of free vacancy and vacancy-Li pair.抄録全体を表示PDF形式でダウンロード (720K) -
鈴木 寿, 林 宏爾, 谷口 泰朗, 松原 秀彰1980 年 44 巻 11 号 p. 1210-1216
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーThe deformation characteristics and transverse-rupture strength (T.R.S.) of WC-(1∼30)% Co cemented carbides with medium carbon were studied at 873∼1273 K by means of the three-point bend test at a crosshead speed of 8.3×10−6 m/s; attention was paid to the effects of the carbide grain size (1.3∼3.8 μm) and domain size of the binder phase.
The following results were obtained: (1) The deformation of cemented carbides was generally divided into two parts, that is, the true deformation part under comparatively low stresses and the other part including apparent deformation (due to stable cracks formation) under high stresses. (2) In the alloy with a fixed cobalt content, the deformation became suppressed at high temperatures, in particular at 1273 K, with increasing carbide grain size, leading to the increase in T.R.S. in coarse grained alloy. The phenomena were in contrast to those at low temperatures. The above results at high temperatures would be explained by assuming that dynamic recovery in the binder was apt to be arrested with increasing carbide grain size. (3) Independent of test temperatures, the amount of the apparent deformation became smaller in case of coarse domain size and at the same time T.R.S. increased, owing to the fact that stable cracks could not easily grow along domain boundaries. (4) As a result, it was made clear that T.R.S. of cemented carbides was precisely understood, when bend-deformation behaviors generally affected by the structural factors were taken into consideration.抄録全体を表示PDF形式でダウンロード (932K) -
五十嵐 廉, 柴田 雅裕, 長田 光生1980 年 44 巻 11 号 p. 1217-1223
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーAg-Cd and Ag-Cd-Sn alloys containing 10∼17 mass%Cd and 0.5∼1.5 mass%Sn were oxidized at 973 and 1073 K under oxygen pressures of 2.1×104 and 1.0×105 Pa in order to investigate the precipitation behavior of oxides during internal oxidation. Microstructures, distribution of Cd and Sn in oxides, and oxide phases were investigated by optical microscopy, electron probe X-ray microanalysis, and X-ray diffraction, respectively. Oxidation tendency of solute elements were estimated with an EPMA, by utilizing oxide enrichment produced at the oxidation front when oxidation conditions were changed rapidly to higher temperature and lower oxygen pressure.
The results obtained are as follows:
(1) Massive oxides in Ag-Cd alloys were changed into fine needle-like oxides by addition of Sn. The most remarkable effect was obtained with 0.5%Sn.
(2) Oxide phases precipitating at 973 K were identified as CdO, Cd2SnO4, and CdSnO3. CdO and Cd2SnO4 precipitated at 1073 K.
(3) SnO2 or composite oxides of CdO and SnO2 precipitated followed by precipitation of CdO on the oxides. It was considered that SnO2 converted into composite oxides by reaction with CdO.抄録全体を表示PDF形式でダウンロード (1263K) -
五十嵐 廉, 長田 光生1980 年 44 巻 11 号 p. 1224-1230
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーAg-Cd-Sn alloy wires containing 9.9∼17 mass%Cd and 0.5∼1.5 mass%Sn were oxidized at 873 to 1023 K under an oxygen pressure of 2.1×104 Pa (in air). The depth of the internally oxidized layer, ξ, and an amount of Cd diffused into the oxidized layer from the unoxidized region, JCd, were measured in order to investigate the behavior of solute elements and oxygen during internal oxidation.
The results obtained are as follows:
(1) The relationship between the depth of the internally oxidized layer and the oxidation time was expressed by the following equation:
(This article is not displayable. Please see full text pdf.)
\ oindentwhere R and r are radii of the wire and the unoxidized region after oxidation for t, respectively.
(2) k was increased by addition of Sn of NSn0=0.4×10−2 and decreased with increasing content of Sn of NSn0≥0.4×10−2 at over 973 K. But k was increased by adding Sn of 0.4×10−2≤NSn0≤1.4×10−2 at the total content of solute elements that an amount of oxygen required to oxidize are the same. k was decreased by addition of Sn of every content at 873 K.
(3) Counter diffusion of Cd was promoted by adding Sn of NSn0>0.4×10−2. Sn of NSn0≤0.4×10−2 did not affect the diffusion of Cd.
(4) Sn changed the shape of oxides into needle-like ones and increased the interface between the Ag matrix and oxide phases along the oxidation direction.
Acceleration of the growth rate of the oxidized layer can be considered to be due to the accelerated diffusion of oxygen brought about by increasing the interface diffusion.抄録全体を表示PDF形式でダウンロード (696K) -
下尾 聰夫, 柴田 芳隆, 木村 弘1980 年 44 巻 11 号 p. 1231-1238
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーThis study was made on the evolution of SiO from CaO-SiO2-Al2O3 slag melted in a graphite crucible with or without carbon saturated iron. The dissolution of carbon in slag was also investigated.
In the absence of metal, the mass loss measured by means of thermo-balance was due to the reaction, (SiO2)+C(s)=SiO(g)+CO(g). And then, in the presence of metal, the mass loss was due to both the reaction shown above and the transfer of silicon to metal, (SiO2)+2C=Si+2CO(g).
The relation between the amount of SiO evolved and the reaction time was linear. The evolution rate of SiO was dependent on the viscosity of slag at the low concentrations of silica and on aSiO2 at the high concentrations, respectively. The apparent activation energies were varied from 298 to 543 kJ/mol corresponding to the slag compositions. The effect of stirring on the evolution rate of SiO was negligible at the small value of aSiO2, but it was significant at the large value of aSiO2.
Under the above experimental conditions, SiO evolution was generally controlled by the breaking of Si-O bonds in slag, but, in the range of small aSiO2 value, the transport of silica also affected the rate.
The dissolution of carbon in silicate slag proceeded slowly and its rate was varied from 2×10−5 to 5×10−5 mol·m−2·s−1 at 1873 K. It was supposed that silicate slag dissolved carbon as both CaC2 and SiC.抄録全体を表示PDF形式でダウンロード (568K) -
Alcock C. B., 一瀬 英爾, Butler J.1980 年 44 巻 11 号 p. 1239-1243
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーThe equilibrium constant K for the reaction
(This article is not displayable. Please see full text pdf.)
\ oindentwas determined over the temperature range of 1023 to 1223 K by a combined method of Knudsen cell mass spectrometry with coulometric titration. The evolution of oxygen through this reaction following a coulometric titration to a steady state was utilized to obtain values of the constant K. This evolution was indicated by the decrease in the ion intensity of In2O+, and it was found to follow an exponential time decay. This procedure of calculation is affected neither by the quantity of electricity applied during the titration nor by the sensitivity of the mass spectrometer. The results obtained can be expressed as function of temperature by the equations.
(This article is not displayable. Please see full text pdf.)
The combination of the value for K with the reported value for the partial pressure of In2O(g) in equilibrium with In(l) and In2O3(s) yields the saturation solubility of oxygen in liquid In which is given by
(This article is not displayable. Please see full text pdf.)
\ oindentwhere XO is the concentration of O in atom fraction.
The technique used in the present investigation also gives the possibility of determining the ionic transport number of the solid electrolyte which was used. The apparent ionic transport number of calcium stabilized zirconia was found to vary from 0.2 to 0.5 with increasing temperature under the present experimental conditions.
The fragmentation ionization coefficient of In2O to In+ at ionization potential of 16 V was also obtained.抄録全体を表示PDF形式でダウンロード (370K) -
荒木 弘安, 平田 健一, 藤村 全戒1980 年 44 巻 11 号 p. 1244-1250
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーMicrostructural change with annealing in a series of cold rolled 18Cr-8Ni stainless steels was studied on three kinds of specimens containing 18% chromium and various nickel contents, which were cold rolled 75% in reduction and then heated for 3.6 ks. The results are as follows: (1) The shape of hardness-temperature curve for specimen containing 8 or 10% nickel was different from that for the specimen of 12% nickel which exhibited no strain induced martensite, and the softening process was divided into two marked stages. (2) The first marked softening stage for either specimen began at around 748 K and subgrains were formed prior to softening at some region in the martensite laths. Corresponding to the softening small austenite grains were formed in the laths along their boundaries. The following softening stage began at around 843 K and recrystallization began in the untransformed austenite. (3) As temperature increased the martensite laths were divided into the small ones by austenite grains which grew more than the width of the martensite laths. The temperatures at which martensites disappeared were around 1023 and 923 K for specimen containing 8 and 10% nickel, respectively. (4) The ending temperatures of recrystallization in the untransformed austenites were around 1023, 973 and 958 K for specimens containing 8, 10 and 12% nickel, respectively. (5) Microstructural change with annealing in the cold rolled metastable austenitic stainless steels seems to start from the recovery in some region of strain induced martensite laths, followed by the formation of austenite grains in the laths along their boundaries and the growth of small recrystallized grains at deformation bands in the untransformed austenite. The ending temperature of recrystallization in the untransformed austenite is approximately the same as that of reverse transformation.抄録全体を表示PDF形式でダウンロード (854K) -
米岡 俊明, 五十嵐 孝雄, 山脇 道夫, 菅野 昌義1980 年 44 巻 11 号 p. 1251-1258
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーOxidation of pure vanadium in 0.133 and 1.33 Pa of oxygen pressure has been investigated at 702∼1087 K by means of a thermoelectrobalance etc., the results of which have been compared with those of the preceding study in oxygen pressures of 13.3 and 133 Pa. Oxidation proceeded according to a parabolic rate law. The Arrhenius plot of the parabolic rate constants showed an obvious discontinuity at around 800 K. The overall activation energy of 104 kJ/mol was obtained for oxidation in the temperature range of 800∼1087 K. Except the pressure dependence of the parabolic rate constant, the present results were quite similar to the preceding ones. Pressure dependence was scarecely observed in the overall oxidation behavior at 800∼1087 K in 1.33∼133 Pa oxygen pressure. On the other hand, obvious pressure dependences were observed in parabolic rate constants at 800∼1087 K and at 702∼751 K in the oxygen pressure range of 0.133∼1.33 Pa and that of 0.133∼13.3 Pa, respectively. To clarify the causes of these behavior, the parabolic rate constants were separated into that for the oxide scale growth and that for the oxygen dissolution into the metal. The mechanisum of the observed pressure dependence for oxidation was discussed.抄録全体を表示PDF形式でダウンロード (782K) -
劉 茂林, 永田 明彦, 和泉 修1980 年 44 巻 11 号 p. 1259-1266
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーSuperconducting properties, Jc and Tc of in situ Cu-22.5 mass%Nb-7∼8 mass%Sn composite wires (φ0.24 mm) were measured to make clear the influence of the heat treatment condition and the Sn content on them. Structures were also observed by an optical microscopy, SEM and EPMA from a metallurgical point of view. The results obtained can be summerized as follows.
(1) The overall Jc increased with increasing heat treatment time at 823 and 873 K, while it scarcely depended on time when heat treated at 923 K. The highest overall Jc at 9 T was 5×108 A/m2, and was obtained after the heat treatment at 873 K for 346 ks.
(2) Tc of about 17 K was attained after heat treatments, but the value was mostly unaltered even if the heat treatment condition varied in the range of 823∼923 K for 86.4∼691 ks.
(3) The EPMA observation showed that the electroplated Sn diffused homogenously to the center of wires after the heat treatment at 873 K for 346 ks. This was in accord with the results of Jc measurement. With the prolonged diffusion process most Sn reacted with Nb fibers to form the Nb3Sn compound and, consequently, there remained little Sn in the Cu matrix. The structural changes of fibers due to the formation of Nb3Sn after heat treatment were also detected by the SEM observation.抄録全体を表示PDF形式でダウンロード (1250K) -
熊坂 一裕, 小野 堅一1980 年 44 巻 11 号 p. 1267-1273
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーMagnetic properties have been investigated in Fe-Co-W alloys containing less than 15%W and less than 40%Co. Specimens were aged at 823∼1273 K after cold swaging by 0∼96% reduction in area. The age-hardening characteristics for these alloys have been observed by measuring electrical resistivity, Vickers hardness, X-ray diffraction, thermal dilatation and electron microscopy. The results obtained are summarized as follows.
(1) Residual induction Br, squareness ratio Br⁄B22.3 and coercive force Hc are raised to maximums by aging near 973 K. These maximum magnetic values become larger with increasing cold swaging reduction in area.
(2) With increasing W content, Br⁄B22.3 and Hc are increased and Br has a maximum at about 13%W. These magnetic properties raised to the maximums at about 20%Co. Magnetic properties with Br: 1.80∼1.92 T and Hc: 5∼8 kA/m are obtained in more than 15%Co and more than 10%W. For instance, Fe-20%Co-13%W alloy shows Br: 1.92 T, Br⁄B22.3: 0.93 and Hc: 5.5 kA/m.
(3) Increasing Vickers hardness and Hc by aging is accompanied with decreasing lattice constant and electrical resistivity of the matrix. Vickers hardness raised to maximum at the aging stage when lattice constant and electrical resistivity close near constant values. Hc reaches a maximum at a more advanced aging stage. It can be considered that the maximum Hc is obtained at the precipitation growth stage. The activation energy in the Hc increasing stage is in the range 290∼340 kJ/mol. This indicates that Hc is raised by the precipitation which is controlled by the W atoms diffusion rate.
(4) Precipitates of the aged alloy after cold rolling are very fine, compared with precipitates of the aged alloy after quenching. This indicates that the fine precipitate structure increases Hc.抄録全体を表示PDF形式でダウンロード (682K) -
堀田 善次, 吉永 日出男1980 年 44 巻 11 号 p. 1273-1281
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーIn order to clarify the high-temperature deformation mechanism in pure metals, the work-hardening rate without dynamic restoring effect, h, and the softening rate without the work-hardening effect, r, are measured by applying the strain-rate change method to the high-temperature deformation of pure aluminum, and their stress and temperature dependences are determined for the steady-state deformation.
By examining the experimental results theoretically, it is shown that the deformation cannot be explained by the widely believed mechanism of lattice self diffusion controlling and the restoring process may not be a single thermally activated process. The results lead us to consider that the dislocation structure in the steady state depends not only on the stress but also on the temperature.抄録全体を表示PDF形式でダウンロード (705K) -
森 克巳, 日和佐 章一, 川合 保治1980 年 44 巻 11 号 p. 1282-1287
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーThe dissolution rate of oxygen into liquid iron at 1873 K was investigated by melting the iron under the FeO-CaO-SiO2 slags in the resistance or induction furnace and determining the oxygen content of iron samples taken at an appropriate time interval. The results are as follows:
(1) The oxygen content in the metal increased nearly exponetially with time. The reaction rate was increased by induction stirring and was deemed to be controlled by the mass transport steps.
(2) Using the two-film theory, overall mass-transfer coefficients were calculated to be 1.3∼4.3×10−3 kg/m2s for runs in the resistance furnace and 4.4∼7.6×10−3 kg/m2s in the induction furnace. The value of mass-transfer coefficient in the metal layer, km, was calculated to be 1.96×10−4 m/s from runs with liquid iron oxide slag and values of ks in the slag layer were 0.2∼3.1×10−5 m/s.
(3) From these values of km and ks it was found that the resistances to the mass transport both in the metal and slag layers were the same order and the reaction was controlled by both steps.抄録全体を表示PDF形式でダウンロード (428K) -
黒澤 文夫, 田口 勇, 松本 龍太郎1980 年 44 巻 11 号 p. 1288-1295
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーCarbides in carbon steels and stainless steels were observed and analyzed using the non-aqueous electrolyte-potentiostatic etching method (abridged as SPEED method).
The results obtained are summarized as follows.
(1) Polarization curves of carbides isolated from steels were measured by the electric conductive paint method in 10% acetylacetone-1% tetramethylammonium chloride-methyl alcohol electrolyte. Carbides such as NbC, TiC, V4C3, ZrC, Mo2C, M7C3, M6C and M23C6 are found to be stable when the steel matrix is etched at baser potentials than +600 mV vs SCE.
(2) In situ observation and analysis of the very fine carbides down to about 10 nm in steels were successfully conducted by the SPEED method.
(3) Crystallographic orientation of chromium carbide (Cr23C6) and the titanium complex precipitate (TiP-TiC) in stainless steel were determined by the analysis of micro facet pits which appeared by etching.
(4) Chromium carbide (Cr7C3) in Ni-base alloy were well observed in comparison with stacking faults, because the faults were harder to be etched than the other parts of the matrix and were easily observed on the sample surfaces.
(5) Cementite (Fe3C) precipitated on the fracture surface of grain boundaries were also well observed by the SPEED method.抄録全体を表示PDF形式でダウンロード (1413K) -
佐貫 須美子, 嶋谷 宏光, 位崎 敏男1980 年 44 巻 11 号 p. 1295-1301
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーThe investigation was carried out to estimate the extraction behaviors of Cu and Pb from the binary solution of metal salts with Versatic Acid 10 diluted in benzen.
The experimental data was compared with the theoretical values for the extraction of metal ions.
The experimental results obtained can be summarized as follows:
(1) The observed values for the extraction of Cu and Pb from the mixed solution coincided with the theoretical values for the extraction of Cu and Pb. Therefore, the extraction for separation of Cu and Pb from the binary solution can be estimated by means of theoretical analysis.
(2) The extraction for separation of Cu and Pb from the binary solution was not dependent upon concentration of Pb2+, but increased with increasing concentration of Cu2+ and NO3−.抄録全体を表示PDF形式でダウンロード (484K) -
中村 藤伸, 楠井 潤, 清水 吉広, 高村 仁一1980 年 44 巻 11 号 p. 1302-1311
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーThe effects of ordering and precipitation on martensitic transformation behaviour in Cu72−xNixAl28 (x=0∼4) alloys have been studied by measuring changes in electrical resistance, 63Cu nuclear magnetic resonance intensity, X-ray diffraction and hardness on isochronal or isothermal ageing of the quenched alloys, with particular reference to the role of Ni in these phenomena. The main results are summarized as follows:
(1) In alloys with low concentrations of Ni (x≤2), the ordering of the β1 phase (DO3 structure) is almost completed during quenching. On ageing after the quench, the equilibrium γ2 phase precipitates coherently with the matrix, impeding the nucleation and growth of the martensite phase. As a result, the Ms temperature is lowered and the hysteresis loop becomes broad and smooth, while in the as-quenched state the loop is narrow and sharply sloping. Further precipitation of γ2, however, raises the Ms temperature owing to the decrease in the Al concentration of the matrix. (2) In alloys with higher concentrations of Ni (x≥3), the ordering of the DO3 structure is not completed during the quench but continues on the subsequent ageing. In addition, the change of structure of β1 from the DO3-type to the Heusler-type ordered structure, accompanied by a rise in Ms temperature, was observed prior to the precipitation of γ2. (3) The ordering of β1 and the precipitation of γ2, during quenching and on subsequent ageing, are retarded by the addition of Ni because the diffusion of Al and Cu is suppressed.抄録全体を表示PDF形式でダウンロード (839K) -
原 信義, 杉本 克久1980 年 44 巻 11 号 p. 1312-1321
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーPassivation and transpassivation films on Mo in 1 kmol/m3-HCl (pH 0.0), -H2SO4 (pH 0.1), and -Na2SO4 (pH 6.0) solutions have been investigated by in-situ modulation spectroscopy. The constituent oxides of the films have been identified by comparing the modulated reflection spectra of Mo with those of several reference Mo oxides and hydroxides.
It was found that both the films formed in these solutions were mainly composed of amorphous MoO2, and that the transpassivation films contained substantial amounts of Mo8O23. Any higher oxides such as Mo4O11 and Mo8O23 were not found in the passivation films. Mo8O23 in the transpassivation films was thought to be formed by the cathodic reduction of HMoO4− ions caused by the anodic dissolution of MoO2 and to exist in the pores of porous MoO2 matrix.抄録全体を表示PDF形式でダウンロード (862K) -
信木 稔, 小口 醇1980 年 44 巻 11 号 p. 1321-1328
発行日: 1980年
公開日: 2008/04/04
ジャーナル フリーIn order to study the hot workability of heat resistant superalloys, compressive tests and forging tests have been conducted at high temperatures up to 1600 K for as-cast materials of Inconel 713C and More 2. Deformability, flow stress and microstructure of deformed material have been examined from the viewpoint of the behaviour of precipitates and inclusion particles. In 713C, a large ductility was obtained in a temperature range of about 50 K at low strain rates. This temperature range corresponded with that of solution of γ′ phase and of recrystallization. At lower temperatures, the ductility was decreased by the fracture of carbides and at higher temperatures by the local grain boundary melting. In the case of More 2, no remarkable increase in ductility was seen. In both materials, the hard and brittle particles were seen to be the cause of decrease in ductility but the lamellar eutictic carbides did not act as the sites of crack initiation. The behaviour of solution and precipitation of γ′ phase and carbides in reheating depended strongly upon the amount of plastic deformation. By forging with lateral compressive stress components, the forging ratio more than 7 was obtained for both materials without cracks.抄録全体を表示PDF形式でダウンロード (1497K)
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