Investigation on Creep Mechanism of a Ni₃Al-Based Single Crystal Superalloy IC6SX under 760°C/540MPa

Abstract:

The creep behaviors of a Ni₃Al-base single crystal superalloy IC6SX prepared by spiral grain selection method was studied systematically under the testing condition of 760/540MPa. The microstructure evolution, movement of dislocations, formation of the dislocation networks and dislocation configuration during the creep process were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the creep performance of the single crystal alloy IC6SX is excellent under 760/540MPa. The experimental results showed that the creep curve of the Ni₃Al-base single crystal superalloy IC6SX was divided into three stages, including decelerating creep stage, steady-state creep stage and accelerated creep stage. The microstructure and the dislocation configuration were different at different stage during the creep and the raft microstructure has not been formed. The creep mechanism was main slipping characterized by dislocation glide mechanism.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 804-809
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.804
• Online since: February 2013
• Authors: Li Wu Jiang, Shu Suo Li, Mei Ling Wu
• Keywords: Creep Mechanism, Dislocation Configuration, IC6SX, Ni₃Al, Single Crystal Superalloy

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