Enhancement of fatigue properties of Al-Mg and Al-Mg-Si alloys at elevated temperatures by addition of small amount of Scandium

添加少量钪提高Al-Mg和Al-Mg-Si合金的高温疲劳性能

• 批准号: 19760063
• 负责人: WATANABE Chihiro
• 金额: $ 2.3万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (B)
• 财政年份: 2007
• 资助国家: 日本
• 起止时间: 2007 至 2009
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-19760063/
• 关键词: 機械材料; 金属疲労; Sc含有Al合金

The effects of small amount of Sc addition on the fatigue properties of Al-Mg and Al-Mg-Si alloys at elevated temperatures have been examined. Cyclic softening after initial hardening is found in the Al-Mg alloys with small Al_3Sc particles, but no cyclic softening takes place in the alloys with larger particles. The cyclic softening is explained by a loss of particle strengthening through particle shearing within strongly strained slip bands. The larger Al_3Sc particles have a stronger retardation effect on the formation of fatigue-induced stable dislocation structure than small particles even at a high temperature. After peak-aging treatments, the Al-Mg-Si alloys has fine lath-shaped β' precipitates. In the Sc-containing Al-Mg-Si alloy, spherical Al_3Sc precipitates of about 11 nm in diameter are co-existed. The Al-Mg-Si alloy with Sc exhibits cyclic hardening to saturation, while the alloy without Sc shows clear cyclic softening after initial hardening. In the Sc-bearing Al-Mg-Si alloy, owing to the existence of non-shearable Al_3Sc precipitates, dislocations were uniformly distributed, resulting in the improvement of fatigue life.

研究了少量Sc添加对Al-Mg和Al-Mg-Si合金高温疲劳性能的影响，在含有小Al_3Sc颗粒的Al-Mg合金中发现了初始硬化后的循环软化，但没有发现。循环软化发生在具有较大颗粒的合金中，循环软化是通过强应变滑移带内的颗粒剪切而导致颗粒强化的损失来解释的。较大的 Al_3Sc 颗粒具有更强的延迟效应。即使在高温下，Al-Mg-Si合金中也能形成比小颗粒更稳定的疲劳诱导的位错结构。 Si合金中，共存有直径约11 nm的球状Al_3Sc析出物，含Sc的Al-Mg-Si合金表现出循环硬化至饱和状态，而不含Sc的合金表现出循环硬化。在含Sc Al-Mg-Si合金中，由于不可剪切Al_3Sc析出物的存在，位错分布均匀，从而提高了疲劳寿命。

项目成果

Al-Mg-Sc合金における高温疲労挙動と転位組織

Al-Mg-Sc合金的高温疲劳行为和位错结构

• 发表时间: 2007
• 作者: 渡邊千尋;石野嘉明;門前亮一
• 通讯作者: 門前亮一

Al-Mg-Sc合金の微視組織と高温疲労挙動

Al-Mg-Sc合金的显微组织及高温疲劳行为

• 发表时间: 2008
• 作者: 渡邊千尋;石野嘉章;門前亮一
• 通讯作者: 門前亮一

Low-cycle fatigue behavior of an Al-Mg-Si alloy with and without a small addition of Sc

添加和不添加少量 Sc 的 Al-Mg-Si 合金的低周疲劳行为

• 发表时间: 2010
• 期刊: Material Science forum (in press)
• 作者: C,Watanabe;R.Monzen
• 通讯作者: R.Monzen

Fatigue behavior and microstructure of an Al-Mg-Sc alloy at an elevated temperature

Al-Mg-Sc合金高温疲劳行为和显微组织

• 发表时间: 2010
• 期刊: Journal of physics CS (in press)
• 作者: C,Watanabe;R.Monzen
• 通讯作者: R.Monzen

Al-Sc系合金中のAl3Sc粒子の粗大化成長

Al-Sc合金中Al3Sc颗粒的粗化生长

• 发表时间: 2009
• 作者: Goto O;Fujishiro M;Kakushima N;Kodashima S;Ono S;Yamaguchi H;Nomura S;Kaminishi M;Omata M;渡邊千尋
• 通讯作者: 渡邊千尋