巻号一覧
48 巻, 9 号
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稲葉 道彦, 本間 美規, 手島 光一, 平尾 修, 桜井 寿春1984 年 48 巻 9 号 p. 863-870
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーCopper base alloys, containing Fe, Ni and Sn up to 2.0 mass%, were soldered using 37 mass% Pb-Sn soft solder and then heated at 423 K for 1.08 Ms (300 h) to grow intermetallic compounds at the solder/alloy interface. Diffusion of additional elements on the interface was analyzed by EPMA. The fractured interface, where the solder was peeled off after the twice 90° bending test, was observed by SEM, and concentrated elements were analyzed by IMA.
Intermetallic compounds formed at the interface were typically η-Cu6Sn5 and ε-Cu3Sn from the solder side to the alloy side. Fe and Ni were concentrated at the ε-phase/alloy interface, and Fe3Sn or Ni3Sn phase containing Cu was observed. On the basis of the observation of the peeled surface, peeling phenomena were roughly classified into 3 types. The first, which was observed on alloys containing only Fe (or Ni) without Sn, was a type indicating the peeling at boundaries of the η-phase and/or the η-phase/ε-phase interface. The second, which was observed on alloys containing Fe (or Ni) and Sn above 0.5 mass%, respectively, was a type indicating the peeling at the Fe3Sn (or Ni3Sn) phase where many voids were formed. The third type was a mixed peeling phenomenon of the above two types, which was observed on alloys containing a few mass percents of Fe (or Ni) or Sn. The diffusion of Cu into the ε-phase resulted in the formation of many voids in Fe3Sn or Ni3Sn phase and the peeling of the solder.抄録全体を表示PDF形式でダウンロード (2742K) -
松岡 才二, 大嶋 隆一郎, 藤田 英一1984 年 48 巻 9 号 p. 871-880
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーIn order to refine the grain sizes of Cu-Al-Ni shape memory alloys, the melt spun technique has been applied. The martensitic transformation, mechanical properties and ageing effects of the alloy ribbons with a mean grain size of a few μm are studied by electron microscopy, X-ray diffractometry, electrical resistance measurements and mechanical tensile tests.
Cu-14 mass%Al-4 mass%Ni alloy ribbons show the Ms temperature by 20 K lower than the bulk material, and not only γ1′ martensite but also β1′ martensite, which appears only by stress application in the bulk material, is thermally-induced in the Cu-Al-Ni alloy ribbons. γ1′ martensite of the ribbons exhibits the same microstructure as that of the bulk material, except the smallness of the {121}γ1′ internal twin width.
In spite of the extraordinary smallness of the grain sizes of the Cu-Al-Ni alloy ribbons, the β1 phase of the material is brittle. The brittleness of the specimen is remarkably improyed without losing a good shape memory effect by addition of a small amount of Ti, Zr, B or Cr, which has a strong affinity for oxygen. It is suggested that the origin of the brittleness of the alloy ribbons is due to intergranular fracture caused by segregation of oxygen at the grain boundaries.
By ageing the β1 phase of the Cu-Al-Ni alloy ribbons between 473 and 673 K, the transformation temperatures are raised prior to degradation of the shape memory effect. This is attributed to the precipitation of the equilibrium α phase and γ2 phase. The increase of the transformation temperatures is performed by Arrhenius type reaction, and the activation energy is determined to be about 67 kJ /mol.抄録全体を表示PDF形式でダウンロード (3769K) -
杉山 昌章, 大嶋 隆一郎, 藤田 英一1984 年 48 巻 9 号 p. 881-889
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーThe thermoelastic martensite transformation from fcc to fct exsits prior to the non-thermoelastic transformation to bct in Fe-Pd alloys containing about 30 at% palladium. The structure of the fcc austenite is a disordered one, similar to In-Tl and Mn-Cu alloys. The temperature hysteresis and volume change in the fcc-fct transformation are small, and the tetragonality of fct martensite phase increases on cooling. The behavior is like the second order transformation. In this study, the specimens with the Ms temperatures between 300 K and 160 K were prepared, and the internal structures of the fcc austenite and fat martensite were precisely examined before and after the fcc-fct transformation by X-ray analysis and optical and electron microscopy. The results are summarized as follows: (1) {110} internal twins were not introduced into a fct martensite in the beginning of the transformation, but rapidly appeared as the tetragonality of a fct martensite increased. (2) Microtwins observed in the in situ electron microscopy were identified as internal twins rather than thin fct martensite crystals. (3) A remarkable tweed pattern was observed in the fcc austenite and the fct martensite phase by electron microscopy. The tweed contrast was closely connected with the internal twins, in such a way that the former grew to the latter during the transformation. (4) The directional arrangement of the tweed pattern was perfectly broken by heating up to 200 K above Ms temperature. This change in the tweed pattern was reversible for cyclic heatings and coolings.抄録全体を表示PDF形式でダウンロード (5297K) -
大西 正己, 下崎 敏唯, 林田 輝樹, 平田 雅治1984 年 48 巻 9 号 p. 890-895
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーThe interdiffusion coefficients in α brass have been determined in the temperature range between 966 and 1183 K by use of three types of diffusion couples. The interdiffusion coefficients at an arbitrary Zn concentration in a given type of the couples subjected to annealing for six distinct durations at a given temperature are distributed within ±17% around the average. ±17% seems to be the accuracy of the coefficients obtained in this experiment.
The Zn concentration at the Kirkendall marker position in all types of the couples trends to decrease slightly with increase of annealing temperature. The multiple markers method developed by Iijima et al. with the aid of Cornet’s analysis has been employed, in order to obtain the intrinsic diffusivities. The intrinsic diffusivity of Zn at a given concentration of Zn in the range between 0 and 20 at% satisfies the Arrhenius relation. When the intrinsic diffusivities, relative to the volume fixed frame of reference, of Zn and Cu are expressed by DZnV and DCuV, respectively, the ratio, DZnV⁄DCuV, increases with the Zn content from 2.6 at 8 at% to 4.1 at 20 at%.抄録全体を表示PDF形式でダウンロード (959K) -
高木 節雄, 瀬尾 武久, 徳永 洋一1984 年 48 巻 9 号 p. 896-901
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーThe microduplex process of a Fe-16%Cr-5%Mo-8%Co-2%Ni alloy has been investigated. The alloy used has a fully ferritic structure after quenching from 1573 K, and then austenite (followed by martensitic transformation during air cooling) decomposes from the ferrite during reheating up to the temperature range of (α+γ) tow phase.
If the ferrite, however, was cold rolled about 90% prior to the reheating, strain induced precipitation of Laves phase occurs in the temperature range 850-950 K. On 923 K aging, the precipitates play an important role in the suppression of subgrain growth, resulting in the fine subgrain structure. It was also shown that austenite nucleates at the subgrain boundaries. On the other hand, in the temperature range 1000-1300 K, austenite immediately nucleates along slip bands and deformation twins, resulting in the microduplex structure of ferrite and martensite. At temperatures above 1300 K where the recrystallization of ferrite matrix can preferentially occur, however, a structure abruptly coarsened. Consequently, to obtain the microduplex structure, it is likely important that the nucleation of austenite should take place prior to the recrystallization of ferrite matrix.抄録全体を表示PDF形式でダウンロード (2030K) -
横川 清志, 福山 誠司, 工藤 清勝1984 年 48 巻 9 号 p. 901-910
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーTensile behavior of ferritic-austenitic two-phase stainless steel (SUS 329J1) was investigated in high pressure hydrogen up to 39.3 MPa at room temperature. Results obtained are as follows:
(1) The ultimate tensile strength and the ductility of the annealed steel decreased with increasing hydrogen the pressure, while no effect of hydrogen on the 0.2% proof stress of the steel was observed. At the starting point of fracture, the quasi-cleavage fracture was observed in the ferritic phase, and the transgranular fracture caused by hydrogen embrittlement was observed in the austenitic phase. On the other hand, at the crack growth area, the cleavage fracture and the tear ridge fracture were observed in the ferritic and the austenitic phase, respectively.
(2) The ultimate tensile strength and the ductility of the steel aged at 748 and 1023 K decreased markedly with increasing hydrogen pressure, because the hydrogen embrittlement susceptibility of the steels increased owing to the phase transformation, while no effect of hydrogen on the 0.2% proof stress of the steel was found.抄録全体を表示PDF形式でダウンロード (2865K) -
岸 輝雄, 大平 貴規1984 年 48 巻 9 号 p. 911-917
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーNew experimental approach, radiation pattern of Acoustic Emission signals, was proposed to estimate the fracture mode of micro-cracking in the materials. Based on the theoretical concept of AE source characterization, the formulation of amplitude and phase in radiated AE signals was established in the case of tensile and shear fracture mode, using the theoretical Green’s function of infinite media.
Fracture toughness testing of side-grooved 7075 aluminum alloy was carried out, using three transducers to detect radiation pattern. Amplitude and phase analysis could verify the tensile mode I cracking in the case of pop-in cracking of this material.抄録全体を表示PDF形式でダウンロード (1330K) -
桝屋 春子, 矢沢 健児, 小沢 和典, 高橋 実1984 年 48 巻 9 号 p. 918-922
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーThe relationship between the microstructure and the magnetic properties of evaporated iron thin films of various thicknesses has been investigated to reveal the reason why iron films more than 100 nm thick evaporated at an incidence angle greater than 75° have high coercive force (Hc) and high squareness ratio (Mr⁄Ms). Iron films were deposited on polyimide films or on glass substrates at an oblique incidence angle of 80° in a vacuum of 1.1×10−3 Pa. To evaluate Hc and Mr⁄Ms, M−H curves were measured using a vibrating sample magnetometer. The morphological structure of the films was observed by examining in a transmission electron microscope cross-sectional specimens prepared by the ultramicrotome method. The crystallographic structure was analyzed by electron diffraction. The structure of films etched chemically after evaporation was also investigated. The results are summarized as follows:
(1) Iron thin films 25 nm thick evaporated at oblique incidence of large angles have relatively low Hc and Mr⁄Ms, whereas the films more than 100 nm thick have much greater Hc\varparallel and (Mr⁄Ms)\varparallel in the direction parallel to the incidence plane.
(2) Iron films evaporated at oblique incidence of large angles consist of two layers. The lower layer, less than 40 nm thick, shows a narrow columnar structure composed of fine crystallites and has chemical activity. The upper layer consists of wider columns, with interstices, composed of greater crystallites. The films evaporated on polyimide substrates have smaller crystallites in the lower than the films on glass substrates.
(3) Improvement in Hc\varparallel and (Mr⁄Ms)\varparallel is attributable to the columnar structure formed in the upper layer. The magnetic properties do not depend on the texture axis and its orientation.
(4) Chemical etching results in the formation of iron films less than 100 nm thick with a high Hc\varparallel and a good (Mr⁄Ms)\varparallel.抄録全体を表示PDF形式でダウンロード (1353K) -
下尾 聰夫, 安藤 繁, 木村 弘1984 年 48 巻 9 号 p. 922-929
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーThe rate of MnO reduction from silicate slag melted in a graphite crucible as a reductant has been investigated by means of a thermo-balance. At small values of MnO activity aMnO, a large portion of the produced molten Mn was evaporated, and the rate of Mn evaporation was nearly equal to that of MnO reduction. In particular, at the value of aMnO less than 0.1, the reaction was of the first order in regard to aMnO, and the activation energy was 375 kJ/mol. It was supposed that the reaction at the slag-graphite interface proceeded by the direct reduction, (MnO)+C(s)=Mn(l)+CO(g).
At large values of aMnO, reduction was greatly accelerated by the presence of liquid Mn, because the following reactions occurred at the slag-metal interface:
(This article is not displayable. Please see full text pdf.)
\ oindentThis finding was observed mainly in the MnO-SiO2 binary slags.
It was found that the reaction rate was markedly dependent on the wetting of slag on the graphite crucible wall. In general, with lower aMnO, the slag gave immersional wetting on the graphite, whereas with higher aMnO, it gave adhesional wetting. In the latter, the reduction rate was by 1 or 2 orders of magnitude lower than that in the former. These results were explained by the assumption that the wettability of the slag on a graphite crucible was intimately related to the formation of SiC at the slag-graphite interface.
It might be inferred that the reduction rate was controlled by chemical reactions.抄録全体を表示PDF形式でダウンロード (1086K) -
渡辺 清, 増本 量1984 年 48 巻 9 号 p. 930-935
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーPresent authors have previously reported on the permanent magnet properties of iron-rich Fe-Pt alloys and a new Platiron magnet alloy (Fe-38.5 at%Pt) with a high energy product of 159 kJ·m−3. In this paper is further studied the effects of titanium, vanadium, rhodium, palladium, iridium, gold, aluminium, gallium and germanium on their magnetic properties, with the following results. The permanent magnet properties of Fe-Pt alloys can be improved by addition of a small amount of titanium and vanadium. Especially, the alloy containing 60 at% iron, 39 at% platinum and 1 at% titanium shows the highest maximum-energy-product of 165 kJ·m−3, coercive force of 360 kA·m−1 and residual flux density of 1.0 T when aged at 823 K for 1.8 Ms after water-quenching. Further, the alloy containing 60.5 at% iron, 38.5 at% platinum and 1 at% vanadium shows the highest coercive force of 410 kA·m−1, maximum energy product of 160 kJ·m−3 and residual flux density of 1.04 T when aged at 773 K for 252 ks after water-quenching. But, in the cases of other elements additions, the permanent magnet properties can not be remarkably improved.
It is presumed that the excellent permanent magnet properties of the Platiron magnet alloys are related to the microstructure of γ1 order phase with the L10-type and its high magnetocrystalline anisotropy.抄録全体を表示PDF形式でダウンロード (956K) -
森 信幸, 大城 桂作, 松田 公扶1984 年 48 巻 9 号 p. 936-944
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーApparent viscosity of partially solidified alloys is expected to be extremely influenced by the size and morphology of crystals. An Al-5%Cu alloy was stirred during solidification with a paddle or a columnar rotor, and factors affecting the apparent viscosity and structure of the alloy slurry were investigated.
The apparent viscosity (μ/Pa·s) of the slurry was approximated by the following equation as a function of the rotation speed (n/s−1) between rotor and crucible, the cooling rate (Vc/K·s−1) and the fraction solid (fs).
(This article is not displayable. Please see full text pdf.)
\ oindentwhere A=1.8 (paddle) and 0.9 (columnar rotor).
Primary crystals were broken into fine quasi-spherical particles by the stirring, while some of them coalesced into complicated particles in the slurry.
A relationship was observed between the apparent viscosity and the particle coupling ratio Rn, that is, the ratio of the number (mm−2) of fine quasi-spherical primary particles to the number (mm−2) of complicated particles.抄録全体を表示PDF形式でダウンロード (2314K) -
平岡 裕, 岡田 雅年, 秋山 隆, 山渕 保夫1984 年 48 巻 9 号 p. 945-949
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーIn general most of commercial molybdenum is produced by the powder metallurgy method and is utilized as a superior heat-resisting material in many fields. Moreover, molybdenum is expected to be used as the first-wall components of JT-60 (JAERI Tokamak-60). However, one of major problems on molybdenum, particularly on powder metallurgy molybdenum, is that any sound welded joint is hard to be obtainable. In many cases weld pores are formed on welding and, therefore, ductility of the welded joint is severely degraded.
The object of the present work is to get a sound welded joint without any weld pores by reducing impurity levels in the material. The materials were produced by modifying one or several parts in the ordinary manufacturing process of powder metallurgy molybdenum. Oxygen, nitrogen, carbon and other principal metallic impurities were chemically analysed. The above materials were then subjected to electron-beam-welding by using a melt-run technique, and the soundness of the welded joints was examined by optical microscopy.抄録全体を表示PDF形式でダウンロード (1351K) -
平賀 啓二郎, 石川 圭介1984 年 48 巻 9 号 p. 950-957
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーSolution-treated microstructures of a series of iron-base superalloys in which nickel is partially replaced by manganese for cryogenic applications have been investigated over the temperature range from 1223 to 1423 K. Alloy compositions of Fe-(10-25)Ni-16Cr-(0-18)Mn-2.4Ti-1.5Mo (mass%) were chosen on the basis of nickel- and chromium-equivalents in the Schaeffler diagram. The nickel- and chromium-equivalents of the alloys are 16 to 27 and 17.5, respectively.
Occurrence of chi phase for 0 to 11.5 Mn alloys and chi plus sigma phases for a 18 Mn alloy was observed after solution treatment at 1223 to 1423 K for 7.2 ks. A close relation between the amount of these phases and the average electron concentration (e⁄a) or the average electron-vacancy number (\barNV) of the alloys was found at the respective solutionizing temperatures: The amount of these phases increased with a decrease in the e⁄a value from about 7.85 for 1223 to 1273 K treatments and from about 7.75 for 1323 to 1423 K treatments. Delta ferrite formation was also observed after solution treatment at 1423 K for alloys with e⁄a≤7.7, and the amount of delta ferrite increased rapidly with a decrease in nickel concentration from about 13 mass%.
It was, therefore, concluded that e⁄a≥7.85 (at 1223-1273 K) and e⁄a≥7.75 (at 1323-1423 K) are required for the alloys to have a single austenitic phase by solution treatment.抄録全体を表示PDF形式でダウンロード (2344K) -
平賀 啓二郎, 石川 圭介1984 年 48 巻 9 号 p. 957-964
発行日: 1984年
公開日: 2008/04/04
ジャーナル フリーAged microstructures of a series of Fe-(10-25)Ni-16Cr-(0-18)Mn-2.4Ti-1.5Mo alloys have been investigated by microstructural observations and Vickers hardness measurements. The alloys were solution-treated at 1423 K for 7.2 ks and aged at 973 K for 173 ks and 346 ks. The solutionized microstructures of the alloys were; (a) single-phase austenite (γ), (b) γ+χ(+σ)+small amount of δ ferrite and (c) γ+χ+large amount of δ ferrite. The aged microstructures and hardening responses for the respective solutionized microstructures were as follows :
For (a), the uniform precipitation of γ′ phase was observed. The hardness increase by aging for 173 ks and 346 ks was about 185 Hv and 190-220 Hv, respectively. For (b), the precipitation of χ phase along grain boundaries and intragranular coarse γ′ phase were observed. The aged hardness remarkably decreased with an increase in the amount of χ(+σ) phase in the solutionized microstructure. For (c), the decomposition of δ ferrite into χ+γ phases and a little or no γ′ precipitate in γ grains were observed. Only a small increase in hardness due to the δ ferrite decomposition was obtained by aging for durations up to 346 ks.
Relations between the aged microstructures and the average electron concentration (e⁄a) or the average electron-vacancy number (\barNv) of the alloys have been also discussed.抄録全体を表示PDF形式でダウンロード (2720K)
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