巻号一覧
45 巻, 2 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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岡田 亜紀良, 宇野 良治, 田中 和裕, 中江 仁1981 年 45 巻 2 号 p. 111-117
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーThe TTT diagram for the recrystallization of a cold-rolled Cu-10 at%Al alloy was depicted from the X-ray diffraction data. On the basis of the TTT diagram, two-step annealing procedures were adopted for investigating the effects of recovery and short-range ordering on the recrystallization-texture development.
Application of preliminary annealing (primary annealing) at temperatures below 583 K prior to the recrystallization annealing (at 673 K for 480 s) enhanced the development of the major component of the recrystallization texture and decreased the intensity of the minor one. The primary annealing at 503 K showed the most remarkable effect on the recrystallization. Shorter primary annealing at this temperature suppressed the development of the major component, whereas the prolonged primary annealing enhanced it. This may be due to the competition of the recrystallization with the short-range ordering in the recrystallization front region. A slight increase of the major texture component in the specimens primarily annealed at temperatures higher than 583 K, may have arisen from its nucleation prior to that of the other components.抄録全体を表示PDF形式でダウンロード (591K) -
須田 英男, 渡辺 徹, 見崎 吉成, 田辺 良美1981 年 45 巻 2 号 p. 117-125
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーIn previous papers, we reported that increasing the reducing agent (NaBH4) added into a plating bath resulted in an increase of boron content in the electroless plating Ni-B alloy film, and the structure of the obtained plating film changed continuously as follows:
\ oindent(1) crystal (aggregation of fine crystals)→ (2) quiet fine crystals+amorphous phase→ (3) amorphous phase+quiet fine crystals→ (4) amorphous phase. The microstructure of the Ni-B alloy film deposited by using dimethylamine borane (DMAB) as the reducing agent was also dependent upon concentration of reducing agent in a plating bath. Even in the alloy film with the highest boron concentration, however, it was not a homogenious amorphous phase and contained a very small amount of quiet fine crystals. We called this structure the “amorphous-like structure”.
In this investigation, the crystallization process by heat treatment and the magnetic properties of these Ni-B alloy films were studied. The crystallization temperature of Ni3B from the amorphous phase was 583 K, but below this temperature fine nickel crystals which alredy existed in the as-deposited amorphous-like phase were grown by annealing. Annealing at 623 K crystallized the retained amorphous phase under the nucliation process. The final stable structure of this alloy film was the aggregation of nickel and Ni3B crystals. Furthermore, the amorphous-like Ni-B alloy film showed the anomalous magnetic phenomena as reported in our previous paper that the magnetization vs temperature curve cannot be fitted to the Brillouin function but can be dscribed as a linear or smoth curve which is concave upwardes, although the Ni-B alloy film is feromagnetic.抄録全体を表示PDF形式でダウンロード (880K) -
津崎 兼彰, 牧 正志1981 年 45 巻 2 号 p. 126-134
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーThe effect of cooling rate on the morphology of lath martensite in 18%Ni maraging steel, Fe-18%Ni and Fe-24%Ni alloys was investigated in detail. The alloys were cooled from their austenite states at several different cooling rates using iced brine, water, oil, air or in furnace cooling. The main results obtained are as follows: (1) The sizes of packets and blocks in lath martensite structure are markedly changed with cooling rate. The packet size and block width decrease with increase in cooling rate. This tendency was observed in all three alloys examined. (2) Variations in Ms, Mf and the martensite-temperature curve of lath martensite in Fe-24%Ni alloy with cooling rate are hardly observable. (3) Observations of the formation process of lath martensite structure with the Greninger-Troiano heat treatment indicated that the block regions correspond to the banded region which are clustered with parallel laths, and the packet regions are formed by the growth and coalescence of parallel banded regions. (4) As the cause of the morphology change of lath martensites, it is concluded that the number of banded regions with parallel laths increases with increase in cooling rate, and hence the final block width and packet size becomes smaller.抄録全体を表示PDF形式でダウンロード (1870K) -
松島 成夫, 森野 数博, 野沢 光治, 三宅 孝治1981 年 45 巻 2 号 p. 134-141
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーTension and tensile fatigue tests of annealed and drawn Ta have been performed in vacuum at high temperature. Relations between tensile strength σB and fatigue strength for the annealed and the drawn Ta have been studied. The results obtained are as follows:
(1) Relation between σB and testing temperature T in the range of 1073∼2273 K are approximately given by
(This article is not displayable. Please see full text pdf.)
\ oindentand a point of inflection appears in the lnσB-T curve for the drawn Ta. Parameters A and B for the annealed Ta are 1.69×103 MPa and 2.17×10−3 K−1, and for the drawn Ta below 1600 K 8.40×103 MPa and 2.85×10−3 K−1, and above 1600 K 4.10×103 MPa and 2.40×10−3 K−1, respectively.
(2) Relations among fatigue life N, cyclic tensile stress (of maximum value σo) and T are approximately given by
(This article is not displayable. Please see full text pdf.)
\ oindentwhere Ao and \Bar{B} for the annealed Ta are 3.20×1022 MPa−\Bar{B} and –6.17, and \Bar{B} for the drawn Ta –5.50 and Ao 9.04×1023 MPa−\Bar{B} (below 1600 K) and 2.57×1022 MPa−\Bar{B} (above 1600 K). The inflection points in the lnσo-T curves (for N=constants) decrease to the lower temperature side with the increase of N.
(3) The inflection points of the lnσB-T and lnσo-T curves for the drawn Ta are generated as the result of perfect recrystallization at about 1600 K. Below 2300 K, the tensile and fatigue strengths of the drawn Ta are higher than the strength for the annealed Ta. Above 2300 K, the strength of the drawn Ta is close to that of the annealed Ta, for the grain size of both materials approach the same level.抄録全体を表示PDF形式でダウンロード (1478K) -
太田口 稔, 吉田 静司, 小口 醇1981 年 45 巻 2 号 p. 142-146
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーIn order to study the influence of hydrostatic pressure on the processes of recrystallization and aging of metallic materials, isothermal heat treatments have been done on a cold rolled OFHC copper and a Cu-Be alloy under 0.1 MPa and 800 MPa, and change in hardness with the holding time has been discussed. The results obtained are as follows:
(1) No evident qualitative difference in structure due to pressure was observed in the OFHC copper after the primary recrystallization.
(2) The change in hardness during the primary recrystallization was delayed by applying high hydrostatic pressure, and the time necessary for obtaining a given value of hardness under 800 MPa was about 2.9 times as large as the time under 0.1 MPa. This value is close to 2.5 calculated by assuming that the activation volume of self-diffusion of copper is about 0.7 \Bar{V} (\Bar{V} is the molar volume of copper).
(3) As for the Cu-Be alloy, the increase in hardness was also delayed under high hydrostatic pressure. The time required for coming up to a certain hardness number under 800 MPa was about 2 times as large as the time under 0.1 MPa. Also in this case, a similar value of about 2.2 was calculated by assuming that the activation volume of diffusion of Be atom in copper is 0.55\Bar{V}Cu+0.15\Bar{V}Be (\Bar{V}Cu and \Bar{V}Be are the molar volumes of copper and beryllium, respectively).抄録全体を表示PDF形式でダウンロード (657K) -
向井 楠宏, 石川 友美1981 年 45 巻 2 号 p. 147-154
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーThe pendant drop method has been developed to measure the surface tension of liquid slag in the static and dynamic conditions by controlling the size of the pendant drop with the aid of Pt-Rh (20%) coil in contact with the slag. Surface tension in dynamic condition, that is, during the rapid change of the drop size, shows a tendency to differ from that in the static condition. Surface tension in the static condition and the temperature coefficient of the surface tension were determined for the liquid CaO-SiO2, CaO-Al2O3, and CaO-Al2O3-SiO2 slags in the temperature range from the vicinity of liquidus temperature to 1873 K. SiO2 lowers the surface tension while it raises the temperature coefficient of the surface tension from negative at lower SiO2 contents to positive at higher SiO2 contents of CaO-SiO2 and CaO-Al2O3-SiO2 slags. At constant SiO2 contents of CaO-Al2O3-SiO2 slag, Al2O3 lowers the surface tension except for a narrow range of high SiO2 contents and low Al2O3 contents, while it raises the temperature coefficient of surface tension except for the range of high SiO2 content. The surface tension vs SiO2 content curve shows a tendency to have a hump in the vicinity of wollastonite and gehlenite for the CaO-SiO2 and CaO-Al2O3-SiO2 slags respectively.抄録全体を表示PDF形式でダウンロード (671K) -
小林 俊郎, 橘 敬1981 年 45 巻 2 号 p. 155-164
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーIn cast irons, ductile cast iron has good ductility and toughness, for the graphite morphology is spheroidal in this iron. It seems that the possibility of strengthening and toughening the ductile cast iron lies in the modification of the matrix structure by heat treatment and the addition of alloying elements. In this study, Ni was added to the ductile cast iron and various matrix structures were obtained by heat treatment. The effects of these treatments on the toughness were then examined.
When the Ni added ductile cast iron was transformed isothermally from the (α+γ) eutectoid temperature range after ferritic annealing, the ferrite plus bainite duplex structure was obtained and this structure showed a good combination of strength and toughness. The most suitable condition for this treatment to give good toughness to lower temperatures was investigated. It was also shown that the improvement of low temperature toughness can be achieved by a special heat treatment. Then the Ni added duplex structure ductile cast iron was compared with the ferritic ductile cast iron and the austenitic ductile cast iron by the U-notched Charpy test, fracture toughness test, and tensile test. The Ni added duplex structure ductile cast iron exhibited a good combination of high strength, toughness, and fracture toughness.
It was shown, however, that the transition temperature of the Ni added duplex structure does slightly decrease in the U-notched Charpy test but largely decrease in the unnotched Charpy test. This phenomenon may be due to the transformation induced plasticity effect in the retained austenite phase. It is assumed, therefore, that the main cause in the improvement of low temperature toughness in the Ni added duplex structure results from the stabilizing effect in retained austenite by the Ni concentration into the austenite phase during holding in the (α+γ) range.抄録全体を表示PDF形式でダウンロード (1516K) -
黒澤 文夫, 田口 勇, 松本 龍太郎1981 年 45 巻 2 号 p. 165-173
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーThe β-phase (NiAl) in stainless steel (25%Ni-19%Cr-5%Al) has been studied using the non-aqueous electrolyte-potentiostatic etching method (the SPEED method).
The results obtained were summarized as follows:
(1) The β-phase was found to be stable when the steel matrix was electrolyzed at +1200∼+1500 mV vs SCE in 3% nitric acid-2% perchloric acid-methyl alcohol electrolyte.
(2) Three-dimensional observation of microstructures of the dual phase (γ-δ-ferrite) and the β phase in δ-ferrite of the stainless steel was successfully conducted by the SPEED method.
(3) The β-phase was found in δ-ferrite of the stainless steel. The β-phase was dice-, sphere-and needle-shaped. From the X-ray and electron diffraction analysis of the isolated residues, the β phase was identified as NiAl (bcc, a0=0.288 nm).
(4) The shape of the β phase of the stainless steel at 1423 K changed from dice-like into diamond-like with aging time. The growth mechanism was also discussed.
(5) The growth of the newly found diamond-shaped β phase was oriented to the eight directions of ⟨111⟩. The crystallographic morphology of the β phase was studied by the SPEED three-dimensional observation method.抄録全体を表示PDF形式でダウンロード (1603K) -
黒澤 文夫, 田口 勇, 松本 龍太郎1981 年 45 巻 2 号 p. 173-178
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーCrystallographic morphology of the diamond-shaped β phase in stainless steel (25%Ni-19%Cr-5%Al) has been studied using the non-aqcuous electrolyte-potentiostatic etching method (the SPEED method).
The results are summarized as follows;
(1) The diamond-shaped β phase crystals which existed in the same δ-ferrite phase were found to be identical in morphology. The β phase crystal grows to eight ⟨111⟩ directions. The three typical shapes of the β phase crystal were newly observed from low indexes by SEM.
(2) The three shapes of the β phase were observed by the rotation of the β phase crystal.
(3) The β phase crystals are grown by agglomeration.
(4) The composition of the β phase was found to be (Ni, Fe, Cr)Al by EDX analysis of the residues collected on a silver membrane filter after the non-aqueous electrolyte-potentiostatic isolation.抄録全体を表示PDF形式でダウンロード (723K) -
永野 貢, 林 安徳, 大谷 南海男, 一色 実, 井垣 謙三1981 年 45 巻 2 号 p. 178-183
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーIn order to study the isotope effect and the trapping effect, the diffusion coefficients of hydrogen and deuterium in high purity iron were measurred by the electrochemical alternating current method at temperatures between 222 and 322 K. This method enables us to separate the surface effect from the permeation process, and gives an accurate diffusion coefficient. The diffusion coefficient of hydrogen obtained above 290 K is proposed to be DH (m2⁄s)=4.90×10−8exp(−4200 (J⁄mol)⁄RT), though it was not expressed by a single Arrhenius equation over the whole temperature range studied because of the trapping effect by structural defects and impurity atoms. The activation energies of diffusion for the two isotopes were equal at 4200 J/mol, and the ratio of D0H to D0D was determined to be 1.24, which was slightly smaller than the classical ratio 1.41. At low temperatures, the trapping effect for deuterium was more remarkable than that for hydrogen.抄録全体を表示PDF形式でダウンロード (455K) -
諸住 正太郎, 菊地 迪夫, 菅井 普三1981 年 45 巻 2 号 p. 184-189
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーDiffusion couples of molybdenum with several nitrides, i.e. AlN, BN, Si3N4, TiN, respectively, were heated in vacuum for up to 36×104 s at various temperatures ranging from 1573 to 2173 K. The couples were then examined for composition, growth rate, structure, and hardness of reaction layers, especially for the Mo-BN couple.
Main results obtained are as follows:
(1) In the Mo-AlN system, AlN was sublimated at 1823 K and did not reacted with Mo.
(2) In the Mo-Si3N4 system, Si3N4 decomposed at 1773 K, and Si diffused into Mo and formed three kinds of molybdenum silicides at the surface. The microstructure near the interface between Mo3Si and Mo was observed by transmission electron microscopy.
(3) In the Mo-TiN system, TiN decomposed at 1770 K and Ti diffused into the surface of Mo forming the Mo-Ti solid solution.
(4) In the Mo-BN system, two sublayers of Mo2B and MoB, identified by X-ray measurement, were formed in the surface of Mo at all the experimental temperatures. The layer thickness of the former compound is larger than that of the latter. Apparent activation energy for the growth of overall layer was estimated to be 377 kJ/mol. The hardness of the layer was measured and the microstructure near the interface between Mo2B and Mo was observed by transmission electron microscopy.抄録全体を表示PDF形式でダウンロード (850K) -
市川 理衛, 三輪 謙治1981 年 45 巻 2 号 p. 189-194
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーThe apparent viscosity and the microstructure of a partially solidified hyper-eutectic Al-Mn alloy in a pasty state under stirring were examined, along with aggregation phenomena of the primary intermetallic compounds. Specimens were mechanically stirred with a rotor at 0.33∼8.33 s−1 during continuous cooling from the liquid state, and the apparent viscosity was measured as the value of torque. The value of torque increased with the increase of fine Al4Mn crystals during cooling from the liquidus temperature to the peritectic temperature, and the value decreased steeply through the peritectic temperature and then became nearly constant because of the coarse Al6Mn crystals having appeared in the peritectic. Finally, it increased sharply with the advance of solidification at the eutectic temperature at which the solidification finished. It was observed that part of the Al6Mn crystals were aggregated by stirring and the aggregate coarsened with increasing revolutions of stirring.抄録全体を表示PDF形式でダウンロード (688K) -
1981 年 45 巻 2 号 p. 189b
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリー -
野末 章, 岸 輝雄, 堀内 良1981 年 45 巻 2 号 p. 194-203
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーDuring stable crack growth, crack extension is assumed to be discontinuous and initiation, growth and coalescence of microcracks ahead of a pre-fatigue crack occur. The plane-strain fracture toughness KIC (or GIC) obtained by the ASTM standard corresponds to a 2% increment of crack extension. These criteria are all lacking in physical basis. Fracture criteria should be based upon physical models from the viewpoint of microscopic fracture mechanisms.
In this paper an investigation is made with the aid of AE signal analysis and fractographic observation of quenched and tempered AISI 4340 steel, especially with an attempt to make clear the relationship between AE energy and plane-strain fracture toughness GIC. The cracking modes for stable crack growth of the specimens are intergranular and dimple fracture. The AE energy increases with decreasing GIC, and the dimple fracture is accoustically quiet. From the experimental results it is concluded that the dominant source of detectable AE during the crack propagation is intergranular fracture.
A new concept of GmicroIG (critical value of energy release rate for intergranular micro-fracture), and GmicroD (critical value of energy release rate for dimple fracture) has been proposed as characterizing parameter of a finite crack growth step from the microscopic viewpoint, as well as the experimental evaluation of these micro-fracture toughness terms. The mechanical energies for the crack extension can be obtained by the summation of energies of intergranular and dimple fracture. Therefore the plane-strain fracture toughness GIC (ASTM) can be interpreted in terms of micro-fracture toughness characteristics according to the following relation.
(This article is not displayable. Please see full text pdf.)
\ oindentThere was reasonably good agreement between the experimental results and the relation.抄録全体を表示PDF形式でダウンロード (849K) -
松田 史朗, 杉本 克久1981 年 45 巻 2 号 p. 203-209
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーIn order to gain a better understanding of the changes in surface films with the cathodic formation and anodic decomposition of hydride, the changes in ellipsometric parameters have been measured in situ on a Nb electrode under cathodic and anodic polarization in a 0.5 kmol·m−3-H2SO4 solution. Optical constants of film-free surfaces of Nb metal and Nb hydride were determined by tribo-ellipsometry and used to calculate the thickness and optical constants of the films from the measured values of the parameters.
The Nb electrode with an anodic oxide film was first polarized to a cathodic potential. The transformation of the film from the one with a higher optical constant to the one with a lower optical constant and the formation of hydride layer under the film were observed simultaneously. Although its thickness decreased, the film on the hydride layer was found to remain after prolonged cathodic polarization.
Then, the Nb electrode with a hydride layer was polarized to an anodic potential. The decomposition of hydride layer and the formation of anodic oxide film occurred immediately. The anodic oxide film formed on the Nb hydride layer in this case should be the same as that formed directly on Nb metal because the former had the same optical constant as the latter.抄録全体を表示PDF形式でダウンロード (513K) -
清水 肇, 古山 直行, 石田 洋一, 小野 雅敏, 工藤 隆一1981 年 45 巻 2 号 p. 210-218
発行日: 1981年
公開日: 2008/04/04
ジャーナル フリーCompositional changes of the surface and near-surface layers in Cu/Ni alloys during Ar ion bombardment (3 keV) at temperature from room to 873 K was studied by means of micro-probe Auger spectroscopy (μ-AES), X-ray micro analysis (XMA) and scanning electron microscopy (SEM). After sputtering at room temperature the surface was enriched with nickel by the selective sputtering of copper. The sputtering yield ratio of Cu/Ni was 1.9±0.1 over a wide range of the alloy composition. The yield ratio agreed with the value calculated from the yields of pure metals. With the increase in the specimen temperature further enrichment in nickel occurred at high argon ion densities. The apparent sputtering yield ratio changed from 0.3 to 8.5 during sputtering the 40 at%Ni alloy at 873 K under the ion beam current density from 4×10−4 A/m2 to 4×10−1 A/m2.
The nickel enrichment occurred mainly by the irradiation enhanced diffusion of copper to the surface of the specimen and the selective sputtering of copper during argon ion bombardment. The enhanced diffusion of copper at 873 K resulted in the formation of a copper depletion zone 400∼500 nm in thickness at 873 K for the ion beam current density of 4×10−1 A/m2. The depletion zone was of the order of 1 μm along the grain boundary. SEM observation revealed a large difference in the topographical features of each grain surface both at room temperature and elevated temperatures.抄録全体を表示PDF形式でダウンロード (926K) -
北島 正弘, 野田 哲二, 岡田 雅年1981 年 45 巻 2 号 p. 219-220
発行日: 1981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 (195K)
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