Observations of a〈0 1 0〉 dislocations during the high-temperature creep of Ni-based superalloy single crystals deformed along the [0 0 1] orientation
Observations of a〈0 1 0〉 dislocations during the high-temperature creep of Ni-based superalloy single crystals deformed along the [0 0 1] orientation
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DOI：
10.1016/j.actamat.2006.11.045
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发表时间：
2007-04
期刊：
影响因子：
9.4
通讯作者：
P. Sarosi;R. Srinivasan;G. Eggeler;M. Nathal;M. Mills
中科院分区：
文献类型：
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作者：
P. Sarosi;R. Srinivasan;G. Eggeler;M. Nathal;M. Mills
对一种NASAIR-100高温合金单晶在1000℃、148 Mpa、20h、1.1%应变条件下进行了拉伸蠕变试验。对漂流后产生的位错结构的分析表明，所有三种类型的〈010型〉位错都频繁地存在于γ‘粒子中。这些族中有两个由于施加的应力而没有受到解析力。这些a〈010〉位错的形成是两个不同的a/2〈011〉位错从γ沟道进入的结果。讨论了这些a〈010〉位错运动的可能驱动力，并在此基础上提出了一种新的筏形微结构蠕变回复机制。
A NASAIR-100 superalloy single crystal was tested in tension creep at 1000°C at a stress of 148MPa, for a time period of 20h and to a strain of 1.1%. Analysis of the resulting dislocation structures after rafting was completed reveals the frequent presence of all three types of a〈010〉 dislocations in the γ′ particles. Two of these families experience no resolved forces due to the applied stress. It is proposed that these a〈010〉 dislocations form as a result of the combination of two dissimilar a/2〈011〉 dislocations entering from γ channels. The possible driving forces for the movement of these a〈010〉 dislocations are discussed, and a novel recovery mechanism during creep of rafted microstructures is introduced on the basis of these observations.