巻号一覧
25 巻, 10 号
選択された号の論文の5件中1～5を表示しています
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堀 茂徳, 古城 紀雄, 川口 清一1975 年 25 巻 10 号 p. 361-367
発行日: 1975/10/30
公開日: 2008/07/23
ジャーナル フリーMicrostructural changes that occur during superplastic deformation of the Al-Cu hypo-and hyper-eutectic alloys were investigated. The main results obtained are as follows;
1) The lamellar structure of the cast eutectic alloy is converted to an equiaxed duplex one by deformation at 525°c, and the strain rate sensitivity index of flow stress, m, increases from0.2 to0.6 with such structural changes.
2) Elongation and m show a maximum at the eutectic composition with the equal proportion of two phases; α and CuAl2 (θ).
3) At higher temperatures, flow stress for the eutectic alloy is lower than that for the hypo-eutectic alloys, particularly at lower strain rates.
4) The inherent grain growth of fine grains which occurs during deformation inceases with increasing strain, particularly in the hypo-eutectic alloys.
5) Although grain boundary sliding seems to be the most important mechanism for superplasticity, the other processes also may operate so that the grain boundary sliding process can be accommodated by them in proceeding the superplastic deformation.抄録全体を表示PDF形式でダウンロード (1252K) -
佐藤 四郎, 大越 登1975 年 25 巻 10 号 p. 368-376
発行日: 1975/10/30
公開日: 2008/07/23
ジャーナル フリーTensile tests were carried out on the nine kinds of 6063 tubes, that is, of the outer diameter D = 20, 30 and 50mm each with thickness t = 1, 2 and 3mm.
The principal results obtained were as follows.
1) Proportional test pieces with a constant value of L0/A (L0: gauge length. A: cross-sectional area) are appropriate for tubular specimens in the same way for both circular and rectangular section test pieces.
2) The length of the neck, which was measured along the specimen before the test, was nearly equal to 2D independent of wall thickness of tube.
3) The tubular specimens were plugged at each end for gripping. The length of the constrained region by the shoulder of the plug was about (0.61.0) D independent of wall thickness of tubes.
4) The length of tubular specimen between the shoulders of the plugs, Lc, should preferably be in the range of Lc5 D for the tension tests.
5) The spiral fracture (Photo 1) occurred for the 6063-F tubular specimen in the range of D/t>20
6) Tensile strength of a curved strip specimen cut from the tube was almost identical to that of a tubular specimen.
7) The elongation percentage of a curved strip specimen cut from the tube was nearly equal to that of a tubular specimen when L0/√A was larger than ten.抄録全体を表示PDF形式でダウンロード (973K) -
菊池 正夫, 墨田 修作, 北口 善久, 水野 政夫1975 年 25 巻 10 号 p. 377-383
発行日: 1975/10/30
公開日: 2008/07/23
ジャーナル フリーAging characteristics of Al-Zn-Mg alloys cast into a water-cooled copper mold and a carbon mold were examined by means of hardness measurements, X-ray small angle scattering methods and transmission electron microscopic observations. It was found that the aging characteristics of Al-Zn-Mg cast alloys strongly depended on the cooling rate after solidification; age hardenability decreased as the cooling rate decreased. This effect was further noted for the commercial Al-Zn-Mg alloy containing small amounts of Mn, Cr, Fe, Zr, Si and Ti. These results were cons dered to be due to precipitation of G. P. zones and equilibrium phases during cooling after solidification.抄録全体を表示PDF形式でダウンロード (1380K) -
鈴木 寿, 菅野 幹宏, 荒木 一郎, 坂野 茂治1975 年 25 巻 10 号 p. 384-391
発行日: 1975/10/30
公開日: 2008/07/23
ジャーナル フリーThe Al-4wt%Cu-Sn alloy specimens of 0.11.0mm thickness containing 00.066wt%Sn were solution-treated at 520°c, quenched and subsequently aged at temperatures ranged from 100 to 250°c. The secondary defects which would develop in those specimens were examined in relation to the specimen thickness, Sn contents and aging conditions by means of transmission electron microscopy. The results obtained were as follows.
(1) The defect structure was observed in each specimen only when the specimen was aged, and it changed with the specimen thickness; in other word, dislocation loops were only observed with the disappearence of helical dislocations when the specimen thickness exceeded about 0.3mm.
(2) Using the specimen of about 0.4mm thickness, it was confirmed that the loop size decreased and the loop density increased with increasing Sn contents under a given aging condition. In the specimens with higher Sn contents, they appeared to be almost stable during aging at low temperatures. The width of loop free zone formed near the grain boundary increased with increasing Sn contents and with lowering aging temperature.
(3) Some discussions were given as to the above phenomena, but the true influence of Sn atoms on the defect structure of the binary alloy could not be fully understood.抄録全体を表示PDF形式でダウンロード (2613K) -
軽金属協会・海水淡水化委員会1975 年 25 巻 10 号 p. 392-401
発行日: 1975/10/30
公開日: 2008/07/23
ジャーナル フリーPDF形式でダウンロード (1077K)
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