巻号一覧
53 巻, 8 号
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原勢 二郎, 清水 亮1989 年 53 巻 8 号 p. 745-752
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe mechanism of (100)[001] texture evolution by grain growth was investigated by X-ray diffraction and back-reflection Laue diffraction methods, with the following results.
(1) Sharp (100)[001] secondary recrystallized grains evolved from a primary recrystallized specimen having a major orientation of {236}⟨5 15 9⟩ at 1273 K in the constant rate heating stage during the secondary recrystallization annealing. With the rise of heating temperature, the number of the (100)[001] secondary recrystallized grains increased and the secondary grains with (100)[011] orientation were also observed at 1373 K. At 1423 K a small number of the secondary recrystallized grains with (110)[001] were also observed. At 1473 K the secondary recrystallized grains with (110)[001] orientation disappeared, although the secondary recrystallized texture mainly composed of grains with (100)[001] orientation and a small number of the secondary gains with (100)[011] orientation were observed. The deviation of the secondary recrystallized grains from an ideal (100)[001] orientation increased with the annealing temperature.
(2) The mechanism of the evolution of the (100)[001] texture by secondary recrystauization was found to be due to the highest frequency of Σ7 coincidently oriented grains in relation to the (100)[001] orientation in the matrix texture before the onset of secondary recrystallization. The evolution of the (100)[011] oriented secondary grains at the latter stage of the secondary recrystallization annealing was considered to be due to the second highest frequency of Σ7 coincidently oriented grains in relation to the (100)[011] orientation. The increase in the scatter of the orientation of (100)[001] secondaries from an ideal (100)[001] orientation was considered to be due to the decrease in the frequency of Σ7 coincidently oriented grains with increasing deviation angle from the ideal (100)[001] orientation.
(3) The present results support the hypothesis that grains having the highest frequency of coincidently oriented grains in the matrix can grow largest in the grain growth process.抄録全体を表示PDF形式でダウンロード (1693K) -
羽木 秀樹1989 年 53 巻 8 号 p. 753-758
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe boundary conditions in electrochemical hydrogen permeation through α-palladium have been discussed, and then the diffusion coefficients of hydrogen between 278 K and 333 K have been determined. In the permeation experiment, the changes in electrode potential and current density at the cathodic surface have been found to correspond to those in dissolved hydrogen concentration and hydrogen entry flux at the cathodic surface, respectively. The temperature dependence of the diffusion coefficients of hydrogen free from trapping effect and surface effect in annealed α-palladium specimens is given by DH (m2/s)=2.40×10−7exp(−21.6(kJ/mol)⁄RT).抄録全体を表示PDF形式でダウンロード (653K) -
斉藤 勝男, 木原 諄二, 乙黒 靖男1989 年 53 巻 8 号 p. 759-763
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーInformation about the dislocation behaviour is necessary for the investigation of the discontinuous deformation, and the stress relaxation test is one of the method to obtain it. This study is intended to provide the stress relaxation behaviour of 7075-Al alloy, which exhibits nearly regular load drops in the stress-strain curve. The stress relaxation tests are done at the positions just before (Max position) and after (Min position) the load drop. The relaxed stress ΔR at each position is discussed. In addition, a strain gauge is attached to the specimen in order to keep the specimen strain constant during the relaxation for the sake of obtaining the true telaxation properties of the specimen.
The main results obtained are as follows:
(1) In the case of the strain control, the ΔR is the value obtained when the stiffness of the machine is infinite, and corresponds to the effective stress.
(2) The stress relaxation at a Min position is due mainly to the deformation band formed when the load dropped.
(3) The stress fluctuations during the discontinuous deformation correspond to the internal stress fluctuations by the formation of the deformation band.抄録全体を表示PDF形式でダウンロード (514K) -
山口 勉功, 板垣 乙未生, 矢澤 彬1989 年 53 巻 8 号 p. 764-770
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーHigh-temperature heat contensts of III-V compounds (III: Al, Ga, In V: N, P, As, Sb) were measured over the temperature range 650 to 1550 K using a drop-calorimeter. The heats of fusion of InP, GaAs, InAs, AlSb, GaSb and InSb were determined as 88.17±0.18, 106.72±0.20, 75.83±0.28, 82.48±0.31, 64.91±0.16, and 45.05±0.35 kJ/mol, respectively, at the corresponding melting points of 1340±1, 1514±1, 1221±1, 1327±2, 991±1, and 800±1 K. The heat content and the heat capacity equations were derived by the use of the Shomate function for the solid compounds and least-squares method for the liquid phases. Based on the third law method, Gibbs energy equations of formation were determined from the obtained heat capacity data and are tabulated per compound and per stable phase. The heats of fusion and the melting points of the compounds increase with increasing cohesive energy per bond while the entropies of fusion of the compounds increase with decreasing hybrid polarity.抄録全体を表示PDF形式でダウンロード (770K) -
原 基, 品田 豊1989 年 53 巻 8 号 p. 771-779
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe hot corrosion behavior of Ni-20%Cr-2%W alloy in molten Na2SO4-NaCl mixtures has been examined in comparison with that of Ni-20%Cr alloy by the measurement of corrosion loss, the observation of corrosion morphology and the electrochemical measurement. Particular attention was given to the influence of salt composition and melt temperature. Corrosion loss of Ni-20%Cr-2%W alloy markedly increased accompanying the formation of thick corrosion layer in molten Na2SO4-10% and −25%NaCl mixtures in the neighborhood of 1090 K. Such a hot corrosion was not observed for the alloys tested in the composition range higher than 75%NaCl or the temperature range higher than 1173 K. The anode and cathode reactions for Ni-20%Cr-2%W alloy in the vicinity of the corrosion potential became active with lowering of the corrosion potential in molten Na2SO4-25%NaCl at 1073 K, in which the corrosion loss of the alloy increased. This fact indicates that the hot corrosion of the alloy causted in the particular melt proceeded by an electrochemical process. In addition, the electrochemical studies suggested that the anode and cathode reactions for the hot corrosion of the alloy were preferential dissolution of chromium from the alloy and reduction of the dissolution product, respectively. Such an electrochemical corrosion occurred for the alloy in the melt seemed to be attributed to an inhibition of the formation of a protective surface oxide consisting of Cr2O3 by tungsten in the alloy.抄録全体を表示PDF形式でダウンロード (1132K) -
熊沢 増治1989 年 53 巻 8 号 p. 780-784
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe formation of surface alloy layers through the diffusion annealing of nickel-plated stainless steels was performed. The diffusion annealing was applied in a temperature range from 1173 to 1373 K for 180-600 s in Ar atmosphere to nickel-plated SUS430 and 304 stainless steels. The thickness of the alloy layer, diffusion velocities and distribution of Ni and Cr in the surface layer were estimated from EPMA line analysis. Corrosion tests of the surface alloyed stainless steels were carried out by immersion in 10%H2SO4 solution at 323 K for max. 28.8 ks, exposure to a gas mixture of air containing 20 ppm SO2 at 308 K for 28.8 ks, and cyclic dip in 5%NaCl at 323 K for 1.8 ks and dry in air at 343 K for 1.8 ks.
The results obtained are as follows: (1) The surface alloy layer is rapidly formed by annealing for 300 s above 1173 K, and no nickel layer remains after annealing at 1273 K for 300 s. (2) The thicker the nickel plating and the higher the annealing temperature, the higher is the diffusion velocity. (3) After annealing treatment of the nickel-plated SUS430 and 304, the surface alloy layers are composed of 20 mass%Ni and 13 mass%Cr, and 35 mass%Ni and 15 mass%Cr, respectively. (4) The surface alloyed SUS430 and 304 stainless steels possess higher corrosion resistance than the unalloyed counterparts.抄録全体を表示PDF形式でダウンロード (425K) -
安藤 繁, 木村 弘1989 年 53 巻 8 号 p. 785-791
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe behavior of carbon deposition on Fe-S alloys containing 0-2.15 mass%S under the conditions of intensive carbon deposition was studied by thermogravimetry and metallography to elucidate the effect of sulfur in iron on carbon deposition in carburizing gas. Excessive sulfur over the solubility limit (0.001 mass%S) in iron at 923 K existed as FeS, which precipitated in the grain and along the grain boundaries. Two types of carbon, laminar carbon and filamentous carbon, was observed to deposit on iron and the 0.03 mass%S alloy. In the alloys containing more than 0.36 mass%S, however, only filamentous carbon deposited preferentially on FeS. Kinetic measurements and metallographical observations showed that sulfur in iron, particularly sulfur as FeS, retards carbon deposition and extends the induction period which is the time to take to cause the significant mass gain. FeS was desulfurized to become porous iron, so that in the 2.15 mass%S alloy where it precipitated three-dimensionally along the grain boundaries, its desulfurizing reaction proceeded for a long time because of the gas diffusion into the inside through porous iron. As a result, the 2.15 mass %S alloy had a very longer induction period and caused mass loss during the period.抄録全体を表示PDF形式でダウンロード (1185K) -
西崎 泰, 川原 浩司1989 年 53 巻 8 号 p. 792-798
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe mechanical properties and corrosion resistance of manganese-base alloys cold-rolled in concentrated and 10% HCl, HNO3, H2SO4, HF and H3PO4, and other acidic solutions were examined.
The maximum tensile strength of 1370 MPa was obtained by the cold-rolled Mn-Cu-C alloys. The strength of the Mn-Cr-Ni-Cu alloys showed an intermediate value, that of the Mn-Cu aloys giving a minimum value. The alloys cold-rolled after heating at 1173 K showed embrittlement. Such embrittlement, however, was prevented in most cases by a presolution-treatment prior to heating at lower temperatures. Addition of copper or nickel or both showed a tendency to suppress the embrittlement or to depress the temperature at which the embrittlement would occur.
In the corrosion test, the chromium element was effective for the attack of acidic solutions, in particular for that of nitric solutions; nickel and copper elements were corrosion resistant for reducing solutions. Most of the manganese-base alloys formed corrosion resisting films in the concentrated H2SO4 solution.抄録全体を表示PDF形式でダウンロード (592K) -
宮島 雅史, 川崎 亮, 渡辺 龍三1989 年 53 巻 8 号 p. 799-804
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーDensification and microstructural development of stainless steel powder compacts during hot powder vehicle compaction was investigated. The preheated powder preform, vacuum encapsuled in a borosilicate glass, was compacted in a steel die using preheated alumina granules as a pressure transmitting medium. The condition for the fun-densification was determined as a function of pressure and temperature. Three microstructural features were observed during the compacting process; solutioning of dendritic structure, recrystallization and normal grain growth, which in turn was found to be mainly dependent on preheating temperature. It has been found that a submicron-sized micro-structure is formed during the recrystallization stage. The densification mechanism of the present compaction process has been discussed on the basis of a concept of pressure sintering map.抄録全体を表示PDF形式でダウンロード (1126K) -
百瀬 治1989 年 53 巻 8 号 p. 805-808
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe gas sulfonitriding of steels in a nitrogen base atmosphere was investigated. Test pieces of JIS S45C and SCM440 steels were treated in an atmosphere of the N2, NH3 and H2S mixed gas at 843 K for 8.1-22.5 ks.
It was confirmed by X-ray diffraction that the surface products were Fe1−xS and Fe3N in each specimen. In the microstructure of the treated specimens, the compound layer was observed close to the surface and there was a porous layer over the compound layer. The hardness distribution of the treated specimens showed that the hardness gradually increased toward the inner layer and reached a maximum value. The thickness of the compound layer increased parabolically with treating time. From these results it was found that the gas sulfonitriding of steels by the use of the nitrogen base atmosphere was possible.抄録全体を表示PDF形式でダウンロード (387K) -
信木 稔, 高橋 順次, 辻本 得蔵1989 年 53 巻 8 号 p. 809-813
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーIn order to study the hot workability of TiAl, compressive tests have been conducted at the temperatures of 1200∼1500 K and the strain rates of 10−4∼10−1 s−1 for vacuum arc melted materials weighing about 60 kg and plasma beam melted material weighing about 10 kg.
Maps of the flow stress and deformability for TiAl as the functions of temperature and strain rate are obtained.
The range of good hot-workability for the TiAl single phase material is between 320 and 350 MPa in flow stress. The condition for good workability becomes severer with increasing volume of Ti3Al in the TiAl+Ti3 Al two-phase material; that is, a higher temperature and a lower strain rate are needed in comparison with the TiAl single phase material.
The poor workability in the two-phase material with the lamellar structure of TiAl and Ti3Al results from the facts that deformation is liable to occur heterogeneously and the twinning deformation is active up to higher temperatures.抄録全体を表示PDF形式でダウンロード (866K) -
高橋 輝男, 橋本 雍彦, 香山 滉一郎1989 年 53 巻 8 号 p. 814-820
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe dilute Cu-Al binary alloys were internally oxidized in the temperature range of 973-1323 K, and the effects of Al concentration and internal oxidation temperature on the microstructure after internal oxidation were discussed. The results obtained are as follows.
Two anomalous microstructures made up of large oxide precipitates were produced depending on the Al concentration and internal oxidation temperature. One is a “corn-like structure” consisting of θ-Al2O3 and CuAlO2, which develops parallel to the diffusing direction of oxygen. Another is a “wave-like structure” consisting of α-Al2O3, which develops perpendicular to the diffusing direction of oxygen. For the alloys with solute concentrations of less than about 0.3%Al, there are no anomalous microstructures at the internal oxidation temperatures. In the range of 0.3-0.6%Al, only the corn-like structure develops. In the range of 0.6-1.4%Al, there are the areas of the corn-like structure or the wave-like structure and the coexisting area of both depending on the Al concentration and internal oxidation temperature, in which the corn-like structure spread into the area of high Al concentrations increasing with internal oxidation temperature. In the range of over 1.4%Al, there is only the wave-like structure at all the internal oxidation temperatures. The effects of Al concentration and internal oxidation temperature on the microstructure after internal oxidation was elucidated.抄録全体を表示PDF形式でダウンロード (2353K) -
遠藤 重郎, 大沼 智幸, 弘津 禎彦, 一ノ瀬 幸雄1989 年 53 巻 8 号 p. 821-827
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーCo80Ni20 alloy films with suitable magnetic properties for the high density magnetic recording were prepared by sputtering in the atmosphere of Ar-N2 gas mixture and by subsequent annealing at 593 K in vacuum. Microstructural morphologies and magnetic domain configurations of these films before and after annealing were observed by transmission electron microscopy, and the relation between the microstructures and magnetic properties was studied. As-sputtered films are non-magnetic and have amorphous structures due to the inclusion of nitrogen atoms. After the annealing, however, most of the nitrogen diffused out from the films and showed hard magnetic properties. A high coercivity of about 80 kA/m was obtained for the film prepared under a certain nitrogen content in sputtering. The electron microscopic observation of the high coercivity films showed that the ferromagnetic Co80Ni20 crystanllites with a (001) in-plane orientation are isolated individually by pore-like amorphous non-magnetic regions containing 30-50 mol% nitrogen. By the Lorentz electron microscopic observation, it was shown that the magnetic domain is finely configurated in the case of the high coercivity films. The high coercivity obtained in this study was explained well by the single domain particle theory.抄録全体を表示PDF形式でダウンロード (1223K) -
野城 清, 上坂 伸哉, 荻野 和巳1989 年 53 巻 8 号 p. 828-833
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーThe validity of the sessile drop method was examined to determine the wettability of the SiC fibre which has a finite curvature and contact angles of liquid pure Cu, Sn and Ag were measured on 2 types of SiC fibres.
Main results are as follows:
(1) The sessile drop method is applicable to measure the contact angle of liquid metal on SiC fibre which has a finite curvature.
(2) Liquid pure metal (Cu, Sn and Ag)/SiC fibre systems are non-wetting ones.
(3) The results obtained are comparable with the previous work for SiC substrate.抄録全体を表示PDF形式でダウンロード (721K) -
後藤 和弘, 永田 和宏, 張 力偉1989 年 53 巻 8 号 p. 834-835
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーPDF形式でダウンロード (185K) -
張 力偉, 後藤 和弘1989 年 53 巻 8 号 p. 836-837
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーPDF形式でダウンロード (133K) -
下尾 聰夫, 水滝 房吾1989 年 53 巻 8 号 p. 838-839
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーPDF形式でダウンロード (139K) -
高橋 裕, 森 実, 石田 洋一, 板東 義雄1989 年 53 巻 8 号 p. 840-841
発行日: 1989年
公開日: 2008/04/04
ジャーナル フリーPDF形式でダウンロード (212K)
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