巻号一覧
46 巻, 1 号
選択された号の論文の8件中1～8を表示しています
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研究論文
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藤谷 渉, 馬越 佑吉1996 年 46 巻 1 号 p. 3-8
発行日: 1996年
公開日: 2007/03/30
ジャーナル フリーBinary Mg–Li and ternary Mg–Li–Zr alloys with α or β single phase, and (α+β) two phases were cold rolled and then annealed at temperatures between 325 K and 525 K. Softening and recrystallization processes of these alloys were investigated by micro Vickers hardness measurement, and optical and electron microscopic observation. The recrystallization of the binary alloy with the α phase occurred at 360 K, and deformation twins and slip bands acted as nuclei for new recrystallized grains. Addition of Zr suppressed the recrystallization and the recrystallization temperature of the ternary alloy was about 90 K higher than that of the binary alloy. The (α+β) phases were effective in suppressing the recrystallization and softening of these alloys at high temperatures, because needle-like precipitates formed in β phase during annealing and they suppressed grain growth.抄録全体を表示PDF形式でダウンロード (1337K) -
池野 進, 古田 勝也, 寺木 武志, 松田 健二, 穴田 博, 上谷 保裕1996 年 46 巻 1 号 p. 9-14
発行日: 1996年
公開日: 2007/03/30
ジャーナル フリーIn order to compare with the aging processes of alumina particle dispersed Al–Cu–Mg alloy composites which was revealed previously, those of alumina particle dispersed Al–4.0 mass%Cu alloy composites and SiC particle dispersed Al–4.1 mass%Cu–1.6 mass%Mg alloy composites were investigated by micro-vickers hardness test, electrical resistivity measurement and transmission electron microscope observation. When alumina particle sizes were differed from 1 to 15 μm at constant volume fraction as 5 vol%, both the GP zone and θ′ intermediate precipitates were appeared during aging. And the time requrired to make a maximum by aging was not changed with alumina particle size. But when the volume fraction of alumina particles increased, the time to reach maximum hardness by aging obviously decreased. Then the effects of alumina particle addition to Al–Cu alloy were the acceleration of aging process. At SiC particle dispersed composite materials, S' intermediate precipitates, rod-like θ′ intermediate precipitates and rectangular shaped σ phases coexisted at relatively later stage of aging. The time to reach maximum hardness by aging of the composites was retarded as compared with that of mother alloy. Then the effects of SiC particle adittion to Al–Cu–Mg alloy were the retardation of aging process.抄録全体を表示PDF形式でダウンロード (1543K) -
常川 雅功, 林 典史, 宇野 照生1996 年 46 巻 1 号 p. 15-20
発行日: 1996年
公開日: 2007/03/30
ジャーナル フリーThe effect of casting conditions on the butt shape of DC aluminum slab was investigated by measurement of the butt curl, the bow and the bow height after casting. The butt curl started from secondary cooling point, and increased with the side shell growth. For example the butt curl increased with casting speed or casting temperature. Also, it became clear that the bow occurred by narrow side shell inclining to inside, the butt curl and the bow were in a body. The relations of the bow and casting conditions had same tendency as that of the butt curl and them. In addition, the bow height was seriously affected by the effective mold length because the bow height depended on the distance from the secondary cooling point to the top of narrow side shell.抄録全体を表示PDF形式でダウンロード (909K) -
山田 銑一, 加藤 義雄1996 年 46 巻 1 号 p. 21-26
発行日: 1996年
公開日: 2007/03/30
ジャーナル フリーRapidly solidified ribbons of 50 μm and 100 μm in thickness were prepared by a single roll method. Al6Fe, Al12Mo and Al3Fe precipitates are observed in quenched specimens of 100 μm thick ribbons but hardly observed in those of 50 μm thick ribbons. Using the 50 μm and 100 μm thick ribbons, two kinds of alloy bar were produced by hot extrusion at 723 K. The alloy bar made from 100 μm ribbons shows a higher 1000 h creep rupture strength at 573 K∼673 K than the bar made from 50 μm ribbons. The “n” value calculated from the equation ε=k·σn is 7 and 9 for the bars made from 50 μm and 100 μm ribbons, respectively.抄録全体を表示PDF形式でダウンロード (661K) -
柳川 政洋, 安倍 睦, 大家 正二郎1996 年 46 巻 1 号 p. 27-32
発行日: 1996年
公開日: 2007/03/30
ジャーナル フリーEffects of Mg, Si content, additional elements and pre-aging temperatures on the bake-hardenability of Al–Mg–Si alloys were investigated by tensile tests and an electron microscope. The 0.2% proof stress obtained by the short time aging at 170°C increased with increasing Mg2Si content, and it became higher with the following ascending order: pseudobinary system alloys <excess Mg alloys <excess Si alloys. The pre-aging at 100°C was more effective in increasing the bake-hardenability of the alloys than that at room temperature. The additions of Ag, Cu, Zn and Sn on the bake-hardenability of the Al–0.8%Mg2Si–0.5%Si alloy were ineffective, on the contrary the addition of Mn or Cr was effective. The Al–0.8%Mg2Si–0.5%–0.1%Mn (or 0.1%Cr) alloy was found to be the most appropriate for automobile body panels.抄録全体を表示PDF形式でダウンロード (793K) -
柳川 政洋, 安倍 睦, 大家 正二郎1996 年 46 巻 1 号 p. 33-38
発行日: 1996年
公開日: 2007/03/30
ジャーナル フリーIn order to reveal the controlling factors of stretchability in Al–Mg–Si alloys, the Erichsen tests, tensile tests and metallographic observations were carried out. There appeared to be little correlation between tensile elongation and the Erichsen value and good correlation between 0.2% proof stress and the Erichsen value. The Erichsen value increased with the decrease of 0.2% proof stress and increased with the decrease of grain size. Fractographic observation revealed that the frequency of the occurrence of intergranular fracture increased with the increase of 0.2% proof stress, and that the fractography changed from intergranular fracture to transgranular fracture by the grain refinement. Dimple patterns were observed on the intergranular fractured surface and it suggested that precipitates on the grain boundary caused ruptures. These results showed that the decrease of precipitates on the grain boundary or the refinement of grain size was effective for the improvement of stretchability in Al–Mg–Si alloys.抄録全体を表示PDF形式でダウンロード (1177K) -
桐生 雅夫, 奥村 勇人, 鎌士 重晴, 小島 陽, 二宮 隆二, 中津川 勲1996 年 46 巻 1 号 p. 39-44
発行日: 1996年
公開日: 2007/03/30
ジャーナル フリーMg–10 mass%Gd–3 mass%Nd–Zr alloy and Mg–10 mass%Dy–3 mass%Nd–Zr alloy have high strength at elevated temperatures and their application to automotive engine parts is expected. In this paper, the corrosion propeties of these alloys in salt solution are discussed. The corrosion properties are evaluated by immersion test in salt solution and electrochemical impedance spectroscopy (EIS). The corroded surface is also characterized by SEM and XPS analysis. From the results of immersion test, it is found that corrosion resistance of as-cast, solution-treated and peak-aged specimens of these alloys are comparable with that AZ91D which has a good corrosion resistance. From the results of EIS, it is clear that stable protective film on the surface of over-aged specimen is formed in salt solution. The surface of the protective film consists of fine needle like compounds. It is suggested that the compounds are MgO, Mg(OH)2 and 3MgCO3·Mg(OH)2·3H2O stabilized by Gd or Dy from the results of XPS. The compounds play the important role as stable protection film on the surface of over-aged specimens of the examined Mg–RE alloys, and results in higher corrosion resistance of the specimens than that of an AZ91D magnesium alloy.抄録全体を表示PDF形式でダウンロード (1073K)
連載講座
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長谷部 光弘1996 年 46 巻 1 号 p. 45-51
発行日: 1996年
公開日: 2022/02/15
ジャーナル フリーPDF形式でダウンロード (5991K)
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