巻号一覧
22 巻, 8 号
選択された号の論文の7件中1～7を表示しています
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田上 道弘, 芹田 陽1972 年 22 巻 8 号 p. 489-493
発行日: 1972/08/30
公開日: 2008/07/23
ジャーナル フリーAddition of Se was reported to have a stronger effect on refinement of primary silicon in hypereutectic Al-Si alloys than that of P. The present study was conducted to clarify effects of Se addition, holding time and superheating temperature on refinement of primary silicon in an Al-20%Si alloy. Grain size of primary silicon was determined. Changes of microstructures were observed with an optical microscope and an X-ray microanalyzer. When a melt was heated at 900°C for 15min, addition of 0.15% Se resulted in refinement of primary silicon. However, increase of Se up to 0.5% did not show a significant improvement of refining effect. Holding time at 900°C did not affect refining effect of Se. The finest silicon was obtained when 0.5%Se was added to a melt at 1, 200°C for 15min. Grey colored particles were present in primary silicon, at the interface of primary silicon with eutectic structures and in eutectic structures. These grey particles were identified to have Al and Se through a microanalysis by the X-ray microanalyzer. A definite break was observed in a cooling curve of a Se treated specimen when primary silicon started to crystallize. These results were interpreted similarly as the AlP nucleation theory in primary silicon refinement.抄録全体を表示PDF形式でダウンロード (1449K) -
山田 始, 伊藤 元貴, 下家 進1972 年 22 巻 8 号 p. 494-503
発行日: 1972/08/30
公開日: 2008/07/23
ジャーナル フリーEffects of coexistence of Fe and Si and of Mg, Cu and Zn on recrystallization of Al-1.2%Mn alloys were studied. The specimens used were Al-1.2%Mn alloys with additions of (1) 0.4% and 0.8% of Fe plus Si, (2) various amounts of Fe with 0.4% Si and (3) 0.3% to 0.8% of Mg, Cu or Zn. The results obtained are as follows.
(1) When the ratio of Si to Fe was about 3, recrystallization temperature of Al-1.2%Mn alloys without preheating treatment was remarkably increased as it occurred when only Si was added. Heating rates also affected recrystallization temperature. Slow heating, especially at 160°C, raised the recrystallization temperature. This was also true when only Si was added.
When the ratio of Si to Fe was about 1/3, the recrystallization temperature became slightly higher than that of alloys with Fe only. Effect of heating rates on recrystallization temperature was small.
When an ingot was preheated, the recrystallization temperature became lower in any cases and the significant difference of the ratio of Si to Fe on recrystallization was not noted.
(2) When the ratio of Si to Fe in alloys without pre-heating treatment was about 3, influence of heating rates on recrystallization on grain size was reduced remarkably as alloys had only Si. However, when the ratio was about 1/3, this effect was less noted. When ingots were preheated, influence of heating rates became more significant as the Si ratio increased. Alloys with Si and Fe in the ratio of 3 behaved similarly as alloys with only Si.
(3) Mg, Cu and Zn had little effect on recrystallization temperture of Al-1.2%Mn alloys whether ingots were preheated or not.
(4) When ingots were preheated, 0.3% of Mg or Cu produced fine grain size on recrystallization. Even if preheating treatment was not applied, fine grains were produced by the addition of Mg and Cu. However, Mg had slightly larger effect. It was found that more than 0.8% of Mg was needed to produce fine grains, similar to that of preheated Al-1.2%Mn alloys. Zn showed little effect on grain size upon recrystallization whether ingots were preheated or not.
(5) When specimens were preheated, effect of heating rates on recrystallization grain size was decreased by the presence of Mg, while it was hardly affected by Cu and Zn.抄録全体を表示PDF形式でダウンロード (2488K) -
大西 忠一, 中谷 義三, 清水 恭治1972 年 22 巻 8 号 p. 504-511
発行日: 1972/08/30
公開日: 2008/07/23
ジャーナル フリーEquilibrium isothermal phase diagrams were obtained in Al-Mn-Cr alloys with less than 24wt.% of Mn plus Cr. The α solid solution, MnAl6, θ, η and the stable ternaly compound G were identified, The G phase was of body centered cubic lattice with the composition (Mn, Cr) Al12 and was unstable above 590°C. The α solid solution was in equilibrium with MnAl6 or θ above 590°C and was also in equilibrium with the G phase. The G phasc existed in equilibrium with the α solid solution, MnAl6, θ and η respectively. The solubility of Mn and Cr in Al and the solubility limit of the ternary α solid solution were established.抄録全体を表示PDF形式でダウンロード (1652K) -
佐藤 四郎1972 年 22 巻 8 号 p. 512-519
発行日: 1972/08/30
公開日: 2008/07/23
ジャーナル フリーEffect of specimen dimensions on elongation in tensile tests was studied for aluminum alloy sheets, 1100-0, 2024-T3 and 5052-0, of 0.5mm1.5mm in thickness.
The principal results obtained were as follows.
(1) From the tests of material 1100-0, the optimum length of the reduced rection (Lc) was found to be not less than 5W (W; width of the reduced section).
(2) The length of the neck was equal to 5√A for material 5052-0 and 6√A for material 2024-T3 and was independent of the sheet thickness (A; cross section of the reduced section). In tension tests it was desirable that the entire length of the neck was within the gage length. However, it was not necessary to consider the length of the neck to determine the gage length since the length of the neck was very small in thin sheet materials as it occurred in the present study.
(3) The constraining effect of the shoulder on the strain distribution was seen at the point, 0.40.2 times W from the end of the straight section. Thus. Lc should be taken to be larger than L0+0.8W, where L0 was the gage length, to eliminate the effect of the shoulder on elongation.
(4) Tensile specimens of 2024-T3 and 5052-0 with Lc/W>6 were apt to fracture at edges of reduced sections. From this and the result indicated in (1), the optimum length of reduced sections was determined to be 56 times W in tensile tests of thin sheet materials. This was independent of the designation of materials.抄録全体を表示PDF形式でダウンロード (880K) -
佐藤 金司, 嵯峨 常生, 水沢 昭三1972 年 22 巻 8 号 p. 520-528
発行日: 1972/08/30
公開日: 2008/07/23
ジャーナル フリーDrilling machinability of wrought aluminum alloys was studied in terms of cutting resistance, surface roughness and chip formation. The results obtained were as follows.
(1) Both torque and thrust increased in proportion to a feed rate. As cutting speed increased, torque decreased whereas thrust remained nearly constant.
(2) It was generally observed that large torque was needed for soft materials while large thrust was needed for hard materials.
(3) In general, good surface finish was obtained for hard materials. Chip welding on a tool was observed for material 1100. This made drilling of material 1100 more difficult than that of other materials. Damage of deep scratches was easily formed on a finished surface of a hole by a drill edge and welded chips.抄録全体を表示PDF形式でダウンロード (1034K) -
井上 真由美1972 年 22 巻 8 号 p. 529-540
発行日: 1972/08/30
公開日: 2008/07/23
ジャーナル フリーPDF形式でダウンロード (3531K) -
西村 秀雄1972 年 22 巻 8 号 p. i-ii
発行日: 1972/08/30
公開日: 2008/07/23
ジャーナル フリーPDF形式でダウンロード (209K)
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