巻号一覧
35 巻, 6 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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徳田 祥一, 河原 弘道1971 年 35 巻 6 号 p. 541-547
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーAs a series of the work to quantitatively make clear the microsegregation in the abnormal microstructure formed in some titanium alloys, the authors tried, at first, to obtain the working curves for Al, Fe, Cr, Mo and V in titanium alloys with the purpose of quantitative analysis by EPMA. The accuracy of the analysis by means of the working curves and the possible minimum size of area for micro-area-analysis were also examined. The results are as follows:
(1) Working curves were obtained in the form of a quadratic or linear equation for each alloying element which was less than 20 wt% in content, using 43 kinds of standard specimens of titanium and titanium alloys. The distribution rate which was obtained from the regression analysis was more than 99% for each working curve, the error of the working curves being within the range of 0.09∼0.38 wt%.
(2) In quantitative analysis of Ti-Fe binary alloys, the measured Fe concentrations of the α and β phases were compared with those of the α and β phases which were easily assumed from Ti-Fe binary equilibrium diagram, and the results showed good agreement. It was also found that an area of 3 μ square would be sufficient to measure the concentration in the micro-area quantitative analysis.
(3) The quantitative analysis of concentrations in a micro-area, namely the microsegregation analysis of the abnormal microstructures of titanium binary and multiple alloy systems has proved great possibilities by the use of the working curve method with EPMA.抄録全体を表示PDF形式でダウンロード (2142K) -
徳田 祥一, 河原 弘道1971 年 35 巻 6 号 p. 548-554
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーIn order to understand a genetic trend of the microsegregation quantitatively measured by EPMA in transformation of titanium alloys, experiments on the effect of cooling rate from β phase and contents of the alloying element such as Fe and Cr were carried out on Ti-Fe and Ti-Cr binary alloys and on Ti-5Al-2Cr-1Fe alloy.
As a result of the experiment and the examination with parameters such as the segregation index, the effective distribution coefficient and the β stabilizing rate, the genetic trend of the segregation for Fe was larger than Cr and there was a sort of a critical cooling rate under the effect of cooling rate from the β phase.
Electron absorption images showed that this kind of segregation had a certain small area and distributed and scattered around. It was found that the less contents of β stabilizing elements, the larger the genetic trend of the microsegregation, and the trend was reduced with increasing degree of the β stabilizing in the alloys. It was also shown that the genetic trend of the microsegregation on 1 wt%Fe in Ti-5Al-2Cr-1Fe alloy was smaller than that on 1 wt%Fe in Ti-1Fe binary alloy, and that was in the other way on 2 wt%Cr in Ti-5Al-2Cr-1Fe and Ti-2Cr alloys.抄録全体を表示PDF形式でダウンロード (2615K) -
渡辺 俊六, 斎藤 恒三1971 年 35 巻 6 号 p. 554-560
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーDensities of Cu-Sn, Cu-Fe, Cu-Co and Cu-Ni alloys in the liquid state were measured by the maximum bubble pressure method at temperatures between their melting point and 1650°C.
The behavior of molar volume of these alloys did not indicate that of ideal mixing. The deviation of molar volume from ideal mixing was positive in the case of Cu-Fe and Cu-Co alloys and negative in the case of Cu-Sn alloy, and the change of the deviation from positive to negative was observed with the increase in temperature in the case of Cu-Ni alloy.
In the case of Cu-Sn alloy, assuming the presence of clusters in the liquid, the physical properties were discussed.抄録全体を表示PDF形式でダウンロード (1588K) -
藤井 政夫, 熊田 誠1971 年 35 巻 6 号 p. 560-566
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーAn experimental study has been carried out so as to investigate the effects of anions such as CrO42−, WO42−, NO3− and H2PO2− on pitting corrosion and stress corrosion cracking in 18Cr-8Ni stainless steel. The results obtained were summarized as follows:
(1) Efficiency of inhibition by anions against the dissolution of etch pits (active dissolution) decreases in the order: CrO42−, WO42−, H2PO2−>>NO3−. The one by NO3− is not appreciable at all.
(2) Efficiency of inhibition by anions against the initiation of macro pits decreases in the order: NO3−≥CrO42−>WO42−>H2PO2−.
(3) Efficiency of inhibition by anions against growth of macro pits decreases in the order: NO3−>WO42−>CrO42−>>H2PO2−.
(4) Efficiency of inhibition by anions against stress corrosion cracking decreases in order: NO3−>H2PO2−>CrO42−, WO42−.
(5) Marphology of pits and cracks in 18Cr-8Ni stainless steel in boiling 35%MgCl2 solution containing various anions is unique to them. Cross-shaped pits, which are supposed to grow into cracks, initiate in the presence of NO3−. Only a few pits initiate in the presence of a large amount of H2PO2−, whereas fine cracks and a great number of pits initiate in the presence of a small amount of the anion. In the presence of CrO42− or WO42−, pits are found on cracks.
(6) As the oxidizing abiltiy decreases in the order: CrO42−>NO3−>H2PO2−, it seems that there is no relation between the oxidizing ability and the efficiency of inhibition against pits and cracks which are caused by Cl− ion.抄録全体を表示PDF形式でダウンロード (2763K) -
山中 和夫, 井野 博満, 大島 隆一郎, 藤田 英一1971 年 35 巻 6 号 p. 566-574
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーThe ordering process of Fe-Al alloys in the composition range of 19∼25 at%Al was investigated by the Mössbauer effect and transmission electron microscopy.
The Mössbauer spetcra of the specimens containing 21.9∼24.1 at%Al, which were slow cooled with the rate of 1°C/hr, consisted of predominant three components due to the Fe3Al type ordered structure, and gave a contradiction to the idea that both the ordered and disordered phases may coexist in these alloys.
In the dark field electron micrograph taken by the super-lattice reflection, the dark regions which had been considered as the disordered phase by previous investigators were found to be aggregates composed of small domains of Fe3Al ordered structure.
These results suggest that at intermediate temperatures around 450°C the Fe3Al ordered and disordered phases coexist, and as the temperature is lowered, the latter changes to the ordered one with small domains and eventually to a single ordered phase.
Below 21 at%Al, the coexistence of the ordered and disordered phase was observed in the slow cooled specimen with the same cooling rate by the Mössbauer effect and electron microscopy.抄録全体を表示PDF形式でダウンロード (3462K) -
小切間 正彦, 平山 俊成1971 年 35 巻 6 号 p. 575-579
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーIn order to clarify the fatigue mechanisms in stainless steel, three kinds of stainless steels were fatigued and their substructures were observed by transmission electron microscopy. The following results were obtained:
(1) In fatigued 18Cr-40Ni-1.7Mo and 18Cr-8Ni-1.7Mo stainless steels, cell structures are formed and they contain many dislocation loops.
(2) In fatigued 18Cr-8Ni stainless steel (SUS 27), fatigue cracks propagate along intense slip bands.
(3) In fatigued 18Cr-8Ni-1.7Mo stainless steel, extrusions and intrusions in slip bands are observed at the edge of thin foils.
(4) Although much martensite is formed by cold rolling of few per cent in 18Cr-8Ni-1.7Mo stainless steel, no martensite is formed by fatigue of low stress amplitude.抄録全体を表示PDF形式でダウンロード (1956K) -
平田 俊也1971 年 35 巻 6 号 p. 579-584
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーThe dissolution and growth of the precipitates β′ in an Al-1.0 wt%Mg2Si alloy at 350°C has been investigated by the electron microscopic observation and electrical resistivity measurement.
As the precipitates β′ dissolve partly into the matrix at 350°C, a number of dislocations and loops were observed around the growing precipitates β′: At the same time, the stable phase β nucleated at the interface of the growing precipitates.
The electrical resistivity increased with the dissolution of β′ and was subsequently followed by the monotonous decrease due to the growth of β′.
The kinetics of the growth of β′ and the origin of dislocations and loops are discussed.抄録全体を表示PDF形式でダウンロード (2361K) -
大塚 伸也, 片山 巖, 幸塚 善作1971 年 35 巻 6 号 p. 584-589
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーIn the present study, potentiostatic titration with the following electrochemical cell was carried out until the steady current was confirmed in the temperature range of 980°∼1130°C:
(This article is not displayable. Please see full text pdf.)
The changes of current with time were measured and the values of log(I−Isteady) were plotted against time. The relation was nearly linear after several tens of minutes. Based on the tangent of the linear relation, the diffusivity of oxygen in molten silver was determined at four diffirent temperatures.
The diffusivity was described by the following equation, and the result was in good agreement with previous reliable data.
(This article is not displayable. Please see full text pdf.)抄録全体を表示PDF形式でダウンロード (1675K) -
鈴木 進, 佐藤 明子, 田中 紘一1971 年 35 巻 6 号 p. 589-593
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーThe absorption spectra of U (III) in fused LiCl, KCl, and CsCl were measured in the spectrum range from 30000 to 7000 cm−1 at various temperatures between 700° and 890°C.
The visible and near infrared spectra of U (III) in these solutions depend largely upon the solvent cations radius and it is considered that this variation is due to the difference in the co-ordination structure of U (III) in each solution. The co-ordination structures of U (III) are attempted to infer from the following investigations; (i) the significant differences in the chemical properties of fused LiCl, KCl, and CsCl, (ii) the similarity of the chemical properties of the co-ordination structures of U (III) with those of Pu (III) and Am (III) having the known co-ordination structures, and (iii) a comparative tendency of the systematic dfference in the absorption spectra of U (IV) in solid state and fused alkali chlorides with that of U (III). It is assumed, consequently, that U (III) in fused CsCl and KCl media are co-ordinated with six chloride ions, and in fused LiCl, the coexistence of two species of U (III) co-ordinated with six chloride ions or less is reasonable.抄録全体を表示PDF形式でダウンロード (1404K) -
小川 豊, 片野 吉男, 長崎 隆吉1971 年 35 巻 6 号 p. 593-598
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーA transmission electron microscope study was carried out on a Zr-2.5%Nb alloy water-quenched from 1000°C and subsequently aged at 400°, 500° and 580°C. After ageing for 50 hr at 500°C, the precipitates exerted a strain field on the surrounding matrix in the direction nearly perpendicular to the prismatic plane, whereas in the direction approximately perpendicular to the basal plane, the precipitates formed the Windmanstätten structure without strain field in the matrix.
The strain field did not disappear until 1000 hr at 500°C, so the precipitate was thought to correspond to the intermediate phase of β-niobium. The precipitates were thought to be in the form of thin platlets lying on {10\bar1n} planes (n is large and the planes nearly correspond to the {0001} plane) and growing approximately along ⟨1\bar210⟩ directions in the matrix. The mean length of the precipitates was 820 Å after ageing for 1000 hr at 500°C and 700 Å after ageing for 10 hr at 580°C.抄録全体を表示PDF形式でダウンロード (2426K) -
武井 英雄, 中佐 啓治郎, 岡本 昭宏1971 年 35 巻 6 号 p. 599-603
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーThe influence of fatigue accumulation given at various cyclic stresses on the fracture toughness was investigated with the Ni-Cr-Mo steel (SNCM 8) quenched and tempered at 200° or 300°C. The results obtained are as follows:
(1) Fracture toughness KC appears to increase with the increase of fatigue accumulation when the cyclic stress is 70 kg/mm2 (a little larger than fatigue limit stress) or 100∼150 kg/mm2 (about twice as large as the fatigue limit).
(2) When the cyclic stress is 200 kg/mm2, the fracture toughness KC increases with the increase of fatigue accumulation up to 30 or 50% of the fatigue life, but at 70% fatigue accumulation, KC decreases to the value of the material not fatigued.
(3) The variation of pop-in plane-strain fracture toughness KIC is generally smaller than that of fracture toughness KC, probably because the fatigue accumulation is given by plane bending.抄録全体を表示PDF形式でダウンロード (1317K) -
相田 貞蔵1971 年 35 巻 6 号 p. 604-608
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーIn order to obtain basic data on the case in which the surface of Cu-Zn electric contacts was heated at high temperature such as a boilling point by switching arc phenomenon, this study was done.
Rates of evaporation for Cu and Zn have been represented respectively as follows:
(This article is not displayable. Please see full text pdf.)
where WCu, WZn are rates of evaporation in g/cm2·sec, and T is a temperature in °K.
On the other hand, an experimental curve of boilling points for Cu-Zn alloys has been reported as a function of Cu content in the Cu-Zn alloys.
In this paper, the following were investigated by the use of the above experimental curve of the boilling points and values of WCu and WZn calculated from the above formulas:
(1) Relation between temperature T and evaporation rates W of Zn which evaporates from the surface of Cu-Zn alloys heated over the temperature range of 1000 to 2000°K was obtained by a new method of illustration.
(2) Next, the curves of evaporation rates W vs. temperature T illustrated by the new method were compared with the curves observed by R. Hargreaves. The copper contents in the Cu-Zn alloys used in comparison are 47.6, 73.9 and 94.6 wt%.
As the results of comparison, both curves are in good agrement at the range less than about 0.5 g/cm2·sec in the evaporation rates (corresponding to about 17 mmHg in vapor pressure).
(3) Moreover, curves of evaporation energy ε vs. temperature T for the Cu-Zn alloys with various copper contents were illustrated by the use of a relation ε=L×W and a latent heat of evaporation L corresponding to the Cu content in the Cu-Zn alloys. (However, it was assumed that L is not concerned in T.)抄録全体を表示PDF形式でダウンロード (1872K) -
唯木 次男, 佐原 忠士, 清水 謙一1971 年 35 巻 6 号 p. 609-614
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーTransmission electron microscopy and diffraction studies have been carried out on the martensite in a Kovar (Fe-27.5 wt%Ni-17.2 wt%Co). In the martensite, transformation twins were observed parallel to the {112} planes, and a mid-rib of 0.5∼1 μ width was observed with a different contrast from the neighboring region. The orientation relationship between martensite and austenite matrix and the habit plane of martensite plate were of the Nishiyama’s relation and of the {3, 15, 10} type, respectively. These results are the same as those in Fe-Ni alloys, suggesting that the crystallographic properties of martensite are not affected by the addition of Co atom.
Very thin martensite platelets were also observed in the austenite matrix. They had the same crystallographic properties as those of the fully grown thick plates and contained striations parallel to the intersection of the plane of platelet with the plane of transformation twin. These results suggest that the martensite plate does not pass through a transition structure but grows fully without any change from the beginning. The fully grown martensites contained line or planar imperfections of another system besides the transformation twins of the {112} planes.抄録全体を表示PDF形式でダウンロード (2396K) -
木全 秀視, 西 成基1971 年 35 巻 6 号 p. 615-622
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーThe heat treatment of Ag-Be alloys was studied for electrical contacts. Silver alloys containing 0.10, 0.20, 0.45 and 0.56 wt%Be were heated at 820°C in various atmospheres. Atmospheres of the heat treatment were nitrogen, ∼10−3 mmHg, air and oxygen. The hardness of Ag-Be alloys was measured at the cross section.
The results obtained were summarized as follows:
(1) Hardness of Ag-Be Alloys after heat treatment increased to more than Hmv 120. Oxygen in the atmosphere of the heat treatment caused an increase in hardness. Experimental data showed that the hardening mechanism was due to the internal oxidation of Ag-Be alloys.
(2) Ag-0.20 wt%Be alloy was heated at 820°C in still air for 16 hr. After the heat treatment, the change of the beryllium content from the surface to the inner part was determined. Beryllium was concentrated in the hardening zone, while the beryllium depleted zone was formed in the center of samples. Formation of the concentrating and depleting zones of beryllium showed that the diffusion velocity of beryllium in silver could not be neglected as compared with that of oxygen.抄録全体を表示PDF形式でダウンロード (3311K) -
木全 秀視, 西 成基1971 年 35 巻 6 号 p. 623-627
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーSuitable heat treatment of Ag-Be alloys was studied for electrical contacts. To widen the hardening zone and increase the hardness of internally oxidized Ag-Be alloys, silver alloys containing 0.10, 0.20, 0.45 and 0.56 wt%Be were heated under various conditions.
The optimum conditions of heat treatment were as follows:
(1) Atmosphere of heat treatment: still air
(2) Cooling method of samples: oil quenching
(3) Heating temperature: 820°C
(4) Heating period: 4 hr
(5) The suitable Be content was between 0.20 and 0.45 wt%Be
(6) On heat treating by the optimum conditions, the maximum hardness of Ag-Be alloys was Hmv 118 for 0.20 wt%Be and Hmv 154 for 0.45 wt%Be.抄録全体を表示PDF形式でダウンロード (1507K) -
井川 博, 新 成夫, 宮城 政和, 森川 正樹1971 年 35 巻 6 号 p. 628-632
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーThe morphology of the ω phase in β-eutectoid titanium alloys (Ti-Mn, Ti-Fe, Ti-Cr, Ti-Co, Ti-W, Ti-Ni) and β-solid solution titanium alloys (Ti-Mo, Ti-Ta, Ti-V) were investigated by the transmission electron microscopic observation.
Considering the standard of atomic size, the morphology of the ω phase in titanium alloys can be classified into cubic and ellipsoidal types.
The ellipsoidal type ω phase is observed in the titanium alloys with alloying elements of atomic sizes larger than that of V, and the cubic type ω phase is observed in the titanium alloys with alloying elements of atomic sizes smaller than that of V. Besides, the crystal structure of both ω phases is the same hexagonal structure.抄録全体を表示PDF形式でダウンロード (2023K) -
吉井 紹泰, 久松 敬弘, 松村 義一1971 年 35 巻 6 号 p. 633-637
発行日: 1971年
公開日: 2008/04/04
ジャーナル フリーA morphological study of the pitting corrosion of type 304 stainless steel has been carried out in 1N-H2SO4 containing 0.5 N-NaCl at 25°C. Only one pit was developed potentiostatically at 400 mV (vs. SCE., near the critical potential), 450 and 600 mV in the surface area of 0.95 cm2. Pits obtained at various growth stages were all shallow pits, whose mouth radius and depth were determined microscopically.
A linear relationship exists between mouth radius and depth. The former is always larger than the latter and this tendency is increased with increasing potential.
The mouth radius and the depth increase linearly with time. These growth rates also increase with increasing potential. The growth rate of the mouth periphery depends strongly on the potential and is larger than that of the pit bottom.
The amount of electricity determined from integration of the pitting current of the single pit agrees well with the calculated one on the assumption that the pit shape is a spherical segment. Microscopic observation of the cross sections of pits also supports this conclusion. Pits developed potentiostatically are different in shape from those found in the case of accidental damage.抄録全体を表示PDF形式でダウンロード (1310K)
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