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。 Al_3Sc颗粒较小的Al-Mg合金在初始硬化后会出现循环软化，而颗粒较大的合金则不会出现循环软化。循环软化可以通过强应变滑移带内的颗粒剪切导致颗粒强化损失来解释。即使在高温下，较大的Al_3Sc颗粒对疲劳诱导稳定位错结构的形成也比小颗粒具有更强的延迟作用。经过峰时效处理后，Al-Mg-Si合金具有细小的板条状β'析出物。在含Sc的Al-Mg-Si合金中，共存有直径约11nm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的合金在初始硬化后表现出明显的循环软化。在含Sc的Al-Mg-Si合金中，由于不可剪切Al_3Sc析出相的存在，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

Coarsening Kinetics of Al3Sc Precipitates in an Al–Mg–Sc Alloy Aged at 573 K

573 K 时效 Al-Mg-Sc 合金中 Al3Sc 沉淀的粗化动力学

• DOI: 10.2320/matertrans.mrp2007048
• 发表时间: 2007
• 作者: D. Watanabe;C. Watanabe;R. Monzen
• 通讯作者: R. Monzen

Effects of Al3Sc particle size and precipitate-free zones on fatigue behavior and dislocation structure of an aged Al–Mg–Sc alloy

• DOI: 10.1016/j.ijfatigue.2007.05.010
• 发表时间: 2008-04
• 期刊: International Journal of Fatigue
• 影响因子: 6
• 作者: C. Watanabe;R. Monzen;K. Tazaki

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