- |<
- <
- 1
- >
- >|
-
栗原 健輔, Ivan Lobzenko, 都留 智仁, 芹澤 愛2022 年 72 巻 2 号 p. 47-53
発行日: 2022/02/15
公開日: 2022/03/15
ジャーナル フリーNanoclusters formed in Al-Mg-Si alloys affect the aging behavior of the alloys depending on the formation temperature. In the present study, first-principles calculations were carried out to evaluate the two- and three-body interactions between Mg, Si atoms and vacancies in the Al matrix and estimate the effect of local bond structures on the formation of nanoclusters. Monte Carlo simulations were subsequently performed to investigate the stable structure of nanocluster formed in Al-0.95 mass pct Mg-0.81 mass pct Si alloy. We found that the Mg-Si bond and SiVac bond were stable in the Al matrix. The result showed that the solute atoms are easy to aggregate with other types of solute atoms and that Si atom had a strong attractive interaction with a vacancy. Furthermore, Mg-Si-vacancy three-body bond was more stable than Mg-Si two-body bond and Si-vacancy two-body bond in the Al matrix. The results indicate that the nanoclusters in the Al matrix were thermally stabilized by the stable bonds between solute atoms and vacancy. Thus, the electronic structure calculations suggested that inner bonds within a nanocluster played a significant role in not only the thermal stability but also the formation and growth behavior of nanoclusters during aging at low temperatures.
抄録全体を表示PDF形式でダウンロード (1476K)
-
永井 孝直, 諸橋 寛海, 半谷 禎彦, 三ツ木 寛尚, 青木 祥宏, 藤井 英俊2022 年 72 巻 2 号 p. 54-56
発行日: 2022/02/15
公開日: 2022/03/15
ジャーナル フリーIn our previous study, a precursor of porous aluminum consisting of uniform aluminum alloy was foamed by frictional heating during friction stir processing. It was found that the temperature at the tool gradually increased as the tool traversed owing to the heat stored in the steel plate. In this study, a precursor of porous aluminum welding a lower-foaming-temperature ADC12 (Al-Si-Cu) alloy precursor and a higher-foaming-temperature A6061 (Al-MgSi) alloy precursor was foamed during friction stir processing of a steel plate. It was shown that by placing ADC12 in the first-half region of tool traversal and A6061 in the latter half, the precursor can be sufficiently foamed, and porous aluminum consisting of ADC12 and A6061 can be obtained up to the tool traversal speed of 20 mm/min.
抄録全体を表示PDF形式でダウンロード (1945K)
-
袴田 昌高2022 年 72 巻 2 号 p. 58-65
発行日: 2022/02/15
公開日: 2022/05/15
ジャーナル フリーPDF形式でダウンロード (4397K)
-
佐々木 元, 杉尾 健次郎2022 年 72 巻 2 号 p. 66-72
発行日: 2022/02/15
公開日: 2022/05/15
ジャーナル フリーPDF形式でダウンロード (3812K)
- |<
- <
- 1
- >
- >|