Mechanical properties of Al(Sc,Zr) alloys at ambient and elevated temperatures
Mechanical properties of Al(Sc,Zr) alloys at ambient and elevated temperatures
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DOI：
10.1016/s1359-6454(03)00320-3
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发表时间：
2003-09-15
期刊：
影响因子：
9.4
通讯作者：
Dunand, DC
中科院分区：
文献类型：
--
作者：
Fuller, CB;Seidman, DN;Dunand, DC
本研究研究了含有 0.27-0.77 vol.% 平均半径 = 2-24 nm 的 Al-3(Sc,Zr) 沉淀物的三元 Al(Sc,Zr) 合金的机械性能。环境温度下的显微硬度值遵循 Orowan 位错旁路机制的预测，预测大于 2 nm 时会过渡到沉淀剪切机制。在二元 Al(Sc) 合金中添加 Zr 可延迟 350 和 375°C 过时效的开始和动力学，但对峰值显微硬度的大小影响不大。 300°C 蠕变变形的特征是阈值应力，该阈值应力在 2-9 nm 范围内增加，与二元 Al(Sc) 合金的先前结果以及最近开发的考虑位错和相干错配析出物之间的弹性相互作用的通用爬升模型一致。在恒定的析出物体积分数下，Zr 添加不会显着提高 Al(Sc) 合金的抗蠕变性能。 (C) 2003 Acta Materialia Inc. 由 Elsevier Ltd 出版。保留所有权利。
This study investigates the mechanical properties of ternary Al(Sc,Zr) alloys containing 0.27-0.77 vol.% of Al-3(Sc,Zr) precipitates with an average radius = 2-24 nm. Microhardness values at ambient temperature follow predictions of the Orowan dislocation bypass mechanism, with a transition to the precipitate shearing mechanism predicted for larger than 2 nm. Addition of Zr to binary Al(Sc) alloys delays the onset and kinetics of over-aging at 350 and 375 degreesC, but has little influence on the magnitude of the peak microhardness. Creep deformation at 300 degreesC is characterized by a threshold stress, which increases with in the range 2-9 nm, in agreement with prior results for binary Al(Sc) alloys and a recently developed general climb model considering elastic interactions between dislocations and coherent, misfitting precipitates. At constant and precipitate volume fraction, Zr additions do not significantly improve the creep resistance of Al(Sc) alloys. (C) 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.