巻号一覧
56 巻, 1 号
選択された号の論文の18件中1～18を表示しています
- |<
- <
- 1
- >
- >|
-
松村 直巳, 林 常昭1992 年 56 巻 1 号 p. 1-6
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーIn order to crystallize the amorphous Al2O3 film, mass-separated ion beam was irradiated on it. The most effective ions for the transformation was investigated.
Amorphous Al2O3 thin films on Fe substrate prepared by ion beam sputtering were irradiated with one of several ions, under the conditions of accelerating voltage: 180 kV, flux: 1.5×1014 ions/cm2·s, irradiation time: 4200 s, at 458 K.
X-ray diffraction examination showed that the transformation from the amorphous phase to the γ crystal occurred after B, O, Al, Ar ion irradiations. This happened effectively in the sequence Ar<B<Al<O. On the other hand, in the case of He, Ti, Zr, Xe ion irradiations, no transformation was observed.
These phenomena were considered on the basis of not the residual stress but rather the frequency of thermal spikes and displacement spikes and the amount of displacement atoms, which produced by the interaction between ions and substrate atoms. In addition, the energy transfered from the ion to the target atom was thought to be partially responsible for the result.抄録全体を表示PDF形式でダウンロード (1750K) -
井上 博史, 稲数 直次1992 年 56 巻 1 号 p. 7-14
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーThe complete orientation distribution functions consisting of even and odd terms in hexagonal materials were determined by the zero range method using suitable zero ranges estimated from pole figures in order to suppress the appearance of ghost peaks, and the reliability of them was examined in detail for titanium sheets with different textures.
The complete orientation distribution functions obtained by the zero range method are not so sensitive to the size of zero range defined in the Euler space. An optional zero range, however, can be estimated by examining the change in negative value in the orientation function through changing a criterion for the determination of zero ranges in pole figures. The existence of the odd term determined under the estimated suitable zero range leads to a significant decrease of ghost peaks, an increase in intensity of true peaks and a decrease of the negative region in the orientation distribution function. Such a tendency is more pronounced for the textures with a larger zero range. From the results of analysis of the various textures, it has been shown that the orientation distribution function including the odd term is much more reliable than the conventional orientation distribution consisting only of the even term for any texture.抄録全体を表示PDF形式でダウンロード (1151K) -
申 熙澤, 金子 純一, 菅又 信1992 年 56 巻 1 号 p. 15-22
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーAl-Mn-Cr alloys of various compositions were rapidly solidified into solid solutions of extended solid solubilities, and P/M materials were consolidated from rapidly solidified flakes by cold pressing, vacuum degassing and hot extrusion. Age hardening behavior was examined for both rapidly solidified flakes and P/M materials. Significant age hardening was observed for the alloys containing 10 mass% of Mn+Cr. However, extruded P/M materials of these alloys showed higher peak hardness than as rapidly solidified flakes. Hence, such a thermomechanical effect was observed on age hardening of the alloys containing 10% of Mn+Cr, whereas no such effect was observed for the alloys containing 7% or less of Mn+Cr. Therefore, the optinum Mn and Cr contents for age hardening of rapidly solidified Al-Mn-Cr alloys are such that the G phase, (Mn, Cr)Al12, is the only constituent phase beside α-Al, and thus the Al-8Mn-2Cr alloy showed the highest age hardenability.抄録全体を表示PDF形式でダウンロード (2375K) -
佐治 重興, 福本 克治, 中野 元博, 岸田 敬三1992 年 56 巻 1 号 p. 23-29
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーFracture toughness of L-T and L-S orientation specimens was measured by the 3 point bend test at 293, 77.4 and 4.2 K, and the tensile properties were examined at various temperatures in the range form 293 K to 6 K for 8090 aluminum alloy extrusions under the peak-aged condition. The interrelations among the uniform elongation, the work done for tensile fracture, the fracture toughness and the laminated cracking along grain boundaries at low temperatures have been investigated the main results and conclusions obtained are as follows; (1) The uniform elongation and the work done for fracture increased with decreasing temperature from 293 K to about 40 K and slightly decreased below 40 K. The increases in ductility are attributed to the increasing work-hardenability which is due to the increasing difficulty in cross slip of dislocations with decreasing temperature. Improvement in the work done is attributed to the increasing strength and uniform elongation with decreasing temperature. (2) Laminated cracks generated during local deformation after the necking in tensile tests, and the laminated cracking is not caused for the increases in the uniform elongation and the work done with decreasing temperature. (3) Fracture toughness, KQ, of L-T specimens increased with decreasing temperature. The KQ values at 77.4 and 4.2 K were about 16% and 43% lager than that at 293 K, respectively. On the other hand, the laminated cracking on the fractured surface of specimens bend-tested became remarkable at the lower temperatures than that at 293 K, but no meaningfull difference was recognized between laminated cracks at 77.4 and 4.2 K. Thus, the increase in the fracture toughness with decreasing temperature may be due not to the divider model of the laminated cracking proposed by Rao et al., but to the increase in the work done for fracture.抄録全体を表示PDF形式でダウンロード (2870K) -
仲庭 正義, 杉本 孝一, 亀井 清, 中村 康彦, 杉本 隆史1992 年 56 巻 1 号 p. 30-37
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーPolycrystalline specimens of shape memory alloys were used in the present study, including a Cu-13Al-3Ni (mass%) single-phase alloy, three Cu-13Al-3Ni-yTi (y=0.48, 0.93 and 3.75) dual-phase alloys and a trial manufacture of Cu-11.68Al-5.03Ni-2.00Mn-096Ti commercial alloy.
The internal friction maximam Qmax−1 associated with martensitic transformation decreased in inverse proportion to Vx which is the volume fraction of the second phase, “x-phase”. It was found that a small amount of x-phase particles (Vx=0.1) was enough for the alloy to suppress the internal friction peak almost completely. The cause of this suppression was explained by the decreasing ambility of interfaces between martensite and parent phase due to grain boundaries and also due to the existence of finely dispersed particles of x-phase.
As for the dual-phase alloys Young’s modulus in the parent phase temperature range is higher than that in the martensite temperature range. This phenomenon can be explained by considering the effect of coherency, which causes an elastically harder state, at interfaces between parent phase and x-phase. On the contrary, interfaces between martensite and x-phase dose not remarkably contribute to the Young’s modulus, because the interfaces are incoherent. The coherency effect may suggest the possibility of developing new high-elasticity alloys by dispersion of small coherent particles in the matrix of an alloy.抄録全体を表示PDF形式でダウンロード (1086K) -
渡辺 英雄, Roas B., Kabius B., Urban K.1992 年 56 巻 1 号 p. 38-44
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーYBa2Cu3O7−x thin films grown epitaxially on single crystal SrTiO3 substrates have been irradiated with 173 MeV Xe-ions. The direction of the ion beam was parallel to the c-axis. A study of the irradiated films by transmission electron microscopy revealed amorphous regions with diameters of about 5 nm. A cross-sectional view of the specimen showed that these regions represent the ion tracks seen along the irradiated direction. Amorphous regions can act as pinning centers for magnetic flux lines.抄録全体を表示PDF形式でダウンロード (2109K) -
下尾 聰夫, 小林 康裕1992 年 56 巻 1 号 p. 45-52
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーTo sythesize β-SiC powder efficiently, the effect of Fe addition on the mechanism of the carbothermic reduction of SiO2 has been investigated. Using powdered SiO2-graphite mixtures containing Fe2O3 or metalic Fe, the reduction rate has been determined with a thermobalance in an argon atmosphere at 1873 K.
The reduction products were SiC, SiO and Fe-Si alloy. The mole ratio of SiC to SiO increased with increasing Fe2O3, but decreased with increasing metallic Fe.
In the early stage of reaction, the rate equation for interfacial reaction control was applicable to the reduction of SiO2. The additon of Fe2O3 increased the rate constant, k1, because Fe2O3 oxidized the graphite particles to render its surface more porous. The addition of metallic Fe practically unaffected k1.
In the late stage of reaction, the reduction rete was described with Jander’s equation. The rate constant, k2 was not dependent on the additions of Fe2O3 and metallic Fe. The rate-determing step was the solid state diffusion in the continuous SiC layer formed around the graphite particles.
In the transitional stage of reaction of the SiO2-Fe2O3-C mixture, the reduction rate was controlled by the gaseous diffusion through the pores in the SiC film formed incompletely around the porous graphite particles.抄録全体を表示PDF形式でダウンロード (989K) -
檀 武弘, 有冨 敬芳, 小川 一行, 本間 一廣, 木村 隆1992 年 56 巻 1 号 p. 53-59
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーThe purpose of this research is to elucidate an interaction mechanism at an interface between molten iron and magnesia crucible. Pure iron used in the present study has less content of impurities except for oxygen, the content of which is classified into two groupes (15 and 400 mass ppm). Magnesia crucible is commercial dense product. Iron specimen has been molten for 10∼60min at 1600°C under Ar atmosphere in a tungsten mesh-heater furnace. After cooling, the specimen is treated and observed with optical and scanning electron microscopes and a surface roughness detector. And then the specimen interface is analysed with an X-ray probe microanalyser and an analytical electron microscope and identified with an X-ray diffractometer.
The results obtained are as fellows:
(1) Depending on the initial oxygen content in iron specimens, the appearance of the interface between the iron specimen and the magnesia crucible was very different. In the case of low oxygen content (15 mass ppm) in molten iron, the interface of magnesia crucible after melting was the almost same as that before melting except for the very slight corrosion at the grain boundary. On the contrary, the magnesia crucible was extraordinarily attacked by molten iron which had a high oxygen content (400 mass ppm).
(2) Oxygen in molten iron is very interface-active. The dissolved oxygen concentrates on the interface of molten iron and crucible, and forms a single molecular FeO layer at the interface in the case of 400 mass ppm O. On the otherhand, no layer is formed in the case of 15 mass ppm O.
(3) Accordingly, in the former case there may be an oxide phase-oxide phase contact at the interface. The latter interface consists of metal and oxide phases. It is considered that such different combinations cause the different types of attack on the magnesia crucible by molten iron.抄録全体を表示PDF形式でダウンロード (2050K) -
亀田 和夫, 山口 勉功1992 年 56 巻 1 号 p. 60-66
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーThe Activity of the liquid Tl-In alloys has been determined by the emf measurements of the following galvanic cells:
(This article is not displayable. Please see full text pdf.)
The activities of indium and thallium in the Liquid Tl-In alloys show very slight positive deviations from Raoult’s law and do nor agree with the result by Kundys and Terpilowski but agree well with the result by Zheng and Kozuka. The γIn° and γTl° values are estimated to be 1.28 and 1.21 at 900 K and 1.16 at 1050 K, respectively. The α function of indium against NIn does not show a constant value, suggesting no regular solution behavior.
The free energy of mixing at 900 K shows slightly smaller positive values than ΔGid, and the peak value of ΔG is −4.69 kJ/mol at about NIn=0.49. The heat of mixing shows very small positive values, in close agreement with the result by Witting and Müller. The peak value of ΔH is 0.55 kJ/mol at about NIn=0.58. It is shown that the ξ function in liquid Tl-In alloys is a linear equation with compositon and the entropy is closer to that of an ideal solution. Hence the properties of this system appear to be similar to those of a subregular solution.抄録全体を表示PDF形式でダウンロード (896K) -
加藤 雅敏, 榊 孝1992 年 56 巻 1 号 p. 67-73
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーThe corrosion behaviour of 99.83% pure Cr in H2SO4 solutions was investigated by corrosion rate and electrochemical measurements. Particular attension was given to effects of concentrations and temperature of acids.
Cr exhibited much better corrosion resistance in 50%H2SO4 than that for Fe-Cr alloys and Ti at low temperatures up to 350 K. A wide passive potential range with low passive current densities was observed for Cr. The corrosion potential for Cr was nobler and more stable than those for Fe-Cr alloys and Ti. The high corrosion resistance is based on spontaneous passivation due to high stability of air formed oxide film. Cr was, however, severely corroded similary to Fe-Cr alloy and Ti under high temperature conditions higher than 350 K. The corrosion potential shifted to less noble side as a result of depassivation, and then active dissolution of Cr occurred continuously.抄録全体を表示PDF形式でダウンロード (3089K) -
加藤 雅敏, 榊 孝1992 年 56 巻 1 号 p. 74-80
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーThe corrosion behaviour of chromium-base alloys in HCl solutions with a concentration of more than 10% was investigated by measurements of the polarization curves, the change in corrosion potential with time and the average corrosion rate in the temperature range between room temperature and the boiling point.
The corrosion resistance of chromium-base alloys was improved by adding noble metals such as palladium and ruthenium. From the immersion test it was shown that the chromium-base alloys containing more than 0.05 mass% palladium and more than 0.2 mass% ruthenium revealed high corrosion resistance. The addition of molybdenum also improved the corrosoin resistance, but its effect was smaller than that of the additions of palladium and ruthenium, even if 10% molybdenum was added to the alloys.
The additions of palladium and ruthenium to the chromium increased the cathodic current, and decreased the anodic dissolution current as the Cr3+ or Cr2+ ion in the active state. Accordingly the corrosion potential of the alloys shifted to the noble direction and the alloys were easily passivated.
The effect of the palladium and ruthenium additions on the corrosion behaviour of chromium is therefore caused mainly by cathodic depolarization.抄録全体を表示PDF形式でダウンロード (818K) -
吉岡 孝之, 大河内 春乃1992 年 56 巻 1 号 p. 81-88
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーIn order to determine low contents of oxygen in high purity iron, lowering of blank values was investigated. The blank value in an outer crucible was rapidly decreased by adding more than 20 mg of Si and heating at about 2373 K for 80 s. An inner crucible was put into the outer crucible treated with Si and they were degassed at about 2573 K for 120 s. The blank value in the double graphite crucible for 100 s at about 2373 K decreased to less than 0.1 mass ppm O/100 s.
It was found that the blank originating from the apparatus was caused by a small amount of the water adsorbed on the wall of a carrier gas tube connected to the impulse furnace. The blank value was stabilized and decreased to less than 0.01 mass ppm O/150 s by removing the adsorbed water by heating the tube with a ribbon heater at about 403 K, letting the carrier gas flow.
The optimum conditions for the determination of low contents of oxygen in high purity iron were examined. It was necessary that the gas extraction time was over 90 s for the determination of less than 5 mass ppm of oxygen. 0.5∼1 g of Sn was added to the 1 g sample. In the case of surface treatments with chemical etching or electrolytic polishing, the effect of surface oxidation with air was observed after the surface treatment, and the reduction with hydrogen after the surface treatment was effective for the determination of trace oxygen in samples. The RSD was 8.3% for 1.2 mass ppm O and 1.1% for 4.8 mass ppm O in high purity irons. These determined values agreed well with those by charged particle activation analysis.抄録全体を表示PDF形式でダウンロード (2966K) -
吉武 道子, 吉原 一紘1992 年 56 巻 1 号 p. 89-95
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーNb films on Ti and Ti films on Nb were deposited by electron been deposition. The specimens were heated in a vacuum, and the diffusion behavior of the substrate element through the films was studied by Auger electron spectroscopy. The diffusion behavior was compared with that in r.f. magnetron sputter deposited films. The relation between the diffusion behavior and the structure of the films is examined.
In the electron beam deposited films, it was found that Ti diffused the Nb film very rapidly with the 60% activation energy of bulk diffusion, and that Nb did not diffuse the Ti film with rapidly. This diffusion behavior was similar to that in magnetron sputter deposited films. The diffusion coefficient was calculated by using the film thickness as the diffusion distance. The pre-exponential factor was 1.4×10−2m2·s−1, and the activation energy was 226 kJ·mol−1. Ti was concentrated on the Nb film and the chemical state of Ti was metallic without any oxides or carbide. Although the structure of the electron beam deposited film was rather different from that of the magnetron sputter deposited film, the diffusion behavior was almost similar. The rapid diffusion of Ti through the Nb film seems to be caused in order to lower the surface free energy of the Nb film. The actual diffusion distance in the electron beam deposited film was longer than that in the megnetron sputter deposited film, which comes from the difference of the structure of the film. Then, the longer heating time was required to diffuse in the electron beam deposited film than in the magnetron sputter deposited film at the same temperature.抄録全体を表示PDF形式でダウンロード (2958K) -
大参 達也, 田中 康博, 工藤 昌行1992 年 56 巻 1 号 p. 96-103
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーIn the previous paper, the authors reported the refinement of primary silicon crystals in the hypereutectic Al-22 mass%Si alloy ingots produced by the Duplex Casting process with the combination of Al-12 mass%Si alloy as the first melt and Al-32 mass%Si alloy as the second melt. In this study, three possible origins of the refined primary silicon crystals were examined: (1) detachment of eutectic silicon crystals during the remelting process of solidified shell of the first melt, (2) nucleation in the second melt during the mixing process of the first and second melts, and (3) nucleation after complete mixing.
In order to examine the first origin, two combinations of alloy compositions were selected for the Duplex Casting process: Al-33 mass%Cu and Al-32 mass%Si; and (b) Al and Al-44 mass%Si. As a result, the primary silicon crystals were refined even though the first melt was free from silicon in either case. Therefore, the first origin was concluded to be not dominant in the refinement of primary crystals.
The combination of Al-51 mass%Ge alloy and Al-32 mass%Si alloy was selected to examine the second and third origins. The germanium concentration in the refined primary crystals, which was measured by EPMA, was lower than the possible minimum concentration predicted on the assumption that the primary crystals came from the third origin. Therefore the second origin, i.e. nucleation in the second melt, was confirmed as the predominant one.抄録全体を表示PDF形式でダウンロード (1999K) -
安丸 尚樹, 土田 耕三, 佐治 栄治, 伊部 壽夫1992 年 56 巻 1 号 p. 104-110
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーAustenitic type 304 stainless steel with ion-nitrided at 823∼853 K, using a N2-H2 d.c. glow discharge palsma. On that occasion, thin compound layer mainly composed of γ′-Fe4N was removed by emery paper. Secondly, a thin layer of Ti with a thickness of 0.1 μm was deposited on this nitrided specimen and, subsequently, TiN of 1.7 μm was deposited at about 623 K, using an ion-plating technique. By this complex treatment combining ion-nitriding with subsequent ion-plating, surface hardened layers were composed of (i) a thin outermost coating layer of TiN with the hardness of about Hv2200 and (ii) a thick inner diffusion layer of about Hv1100.
The mechanical properties of the specimens TiN-coated after ion-nitriding were examined compared with the untreated or only TiN-coated specimens. The specimens showed a large improved resistance to wear compared with the untreated specimens and the largest wear resistance among them. As for the corrosion resistance, the specimens were a little inferior to the only TiN-coated specimens, but showed an improved resistance to corrosion compared with the untreated specimens. Concerning the resistance to fatigue limit of the specimens was lowered slightly compared with the only ion-nitrided specimens, but showed a considerable improvement compared with the untreated specimens.抄録全体を表示PDF形式でダウンロード (1689K) -
大村 博彦, 川尻 鉱二, 吉田 亨1992 年 56 巻 1 号 p. 111-117
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーThe influence of test temperature on the toughness of the high-strength brazed joint of 0.17%C steel and 1.04%C steel, where base metals were united by the columnar Fe-10∼6%Cu-0.8%C alloys which were deposited from the 1.04%C steel/Cu filler metal (JIS BCu-1) interface due to the dissolution of 0.17%C steel base metal, was investigated in a temperature range from 198 to 873 K. Furthermore, the high-strength joint was compared to the other joints brazed with Au filler metals (BAu-1 to -4), Ni filler metal (BNi-2), Ag filler metal (BAg-8) and Cu-5%Ni filler alloy.
The effect of uniting both base metals by the columnar phase on the Charpy U-notch impact value was remarkable in the range between 373 and 673 K. Particularly at 673 K, the impact value of the joint reached 62 J/cm2 which was about 70% that of the joints brazed with BAu-2 and BAu-4, where the dissolution and deposit did not take place, i.e., no uniting occurred.
In the case of BAu-1 both base metals were also united by the deposited columnar Fe-6∼5%Cu-2∼1%Au-0.8%C alloy so that the impact value of the joint was higher than that for BAu-4 at 673 to 773K. For both BNi-2 and BAg-8, the impact value was extremely low throughout the whole temperature range.
By using the Cu-5%Ni filler alloy or BAu-3 instead of BCu-1 or BAu-1, the composition of columnar phase became Fe-12∼16%Cu7∼15%Ni-0.6%C or Fe-7%Cu3∼8Ni-2∼1%Au-0.8%C, respectively. However, alloying the columnar phase with Ni did not result in the increase in the impact value of the brazed joints.抄録全体を表示PDF形式でダウンロード (4100K) -
富田 友樹, 高谷 泰之, 橋詰 源蔵, 原田 良夫1992 年 56 巻 1 号 p. 118-124
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーIt was found in the previous studies that Ni-Cr-Fe overlay weld alloys containing NbC particles, formed by a plasma powder welding process, had excellent corrosion and wear resistances. Clarification of soidification process of alloys is essential to make clear the mechanism of such improvement of properties. In this study, the solidification structures of alloys containing 5∼60 mass%Fe and 40 vol%NbC has been examined using SEM, TEM, EPMA and XRD.
A part of NbC particles dissolved in a molten alloy caused the crystallization of NbC and M23C6. The morphologies and amounts of these carbides changed largely at 20 mass%Fe. As the Fe content of alloy increased to 20 mass%Fe, the amount of NbC increased and that of M23C6 decreased. However, the amount of carbide deposited was almost constant above 20 mass%Fe. The observations of microstructure revealed that solidification proceeded in the sequence, primary NbC→eutectic (γ+NbC)→eutectic (γ+NbC+M23C6) in alloys with more than 20 mass%Fe. In alloys with iron below 20 mass%, the solidification occurred in the order, primary NbC→primary M23C6→eutectic (γ+M23C6)→eutectic (γ+M23C6+NbC)→eutectic (γ+NbC)→eutectic (γ+α+NbC). The difference in crystallization manner suggested that the free energy for the formation of carbide should change depending upon the activities of Cr and Nb contents in the molten alloy.抄録全体を表示PDF形式でダウンロード (4101K) -
村木 達哉, 谷脇 雅文, 伊藤 秀明, 武笠 幸一1992 年 56 巻 1 号 p. 125-132
発行日: 1992年
公開日: 2008/04/04
ジャーナル フリーThis study was performed in order to establish the heat treatment for substitution of Sn for Cu in high-Tc superconductor YBa2Cu3O7−y. Two methods of YBa2(Cu, Sn)3O7−y preparation were tired. The crystal structure and the impurity phase in the fired samples were examined by X-ray diffraction, and the superconductivity was estimated by the ac-susceptibility measurement. First the substitution of Sn for Cu in CuO prior to the synthesis of YBa2(Cu, Sn)3O7−y was tried and solubility of Sn in CuO was obtained as a function of firing temperature. Since it was found that Sn is substituted for 0.5 at%Cu at most, this preparation method was abandoned. Second, the ordinary firing of the mixture of 2BaCO3, 1/2Y2O3, 3(1−x)CuO and 3xSnO2 was performed. The Sn solubility was obtained as a function of firing temperature from 900°C to 970°C. Sn of x=0.011 dissolves at 960°C. From the lattice constant, it was shown that Sn is substituted not only for Cu(1) site but also for Ba or Y sites in the case of large x and high firing temperature. In the samples fired at high temperatures, Sn doping did not change Tconset but it decreased the superconductive volume mainly by the orthorhombic-tetragonal phase transition. In the samples fired at 900°C, the Meissner signal decreased by 40%, though Sn of only x=0.001 is soluted, which means that Sn may occupy the Cu(2) site in the samples.抄録全体を表示PDF形式でダウンロード (2749K)
- |<
- <
- 1
- >
- >|