The high performance of Ni single crystal superalloys during high temperature low stress creep service, is intrinsically determined by the combined effects of microstructural evolution and the dislocation behaviour. In the field of the evolution of dislocation network, two main recovery mechanism based on dislocation migration dominate the process. One is superdislocations shearing into γ’ rafts through a two-superpartials-assisted approach. Another is the compact dislocations migrating along γ/γ′ interface. These two mechanisms are similarly climb-rate-controlled process. In this work, a model for the minimum creep rate based on thermodynamic and kinetic calculations and using an existing detailed dislocation dynamics model has been built by taking the dislocation migration behaviours as well as the rafted microstructure into consideration, which can well reproduce the ([100] tensile) creep properties of existing Ni superalloy grades, without the need to make the dislocation parameter values composition dependent.

Ni单​​晶高温合金在高温低应力蠕变过程中的高性能，本质上是由微观组织演变和位错行为的综合影响所决定的。在位错网络的演进领域，基于位错迁移的两个主要恢复机制主导着这一过程。一种是通过两个超局部辅助方法将超位错剪切成γ'筏。另一个是沿γ/γ'界面迁移的致密位错。这两个机制是类似的爬升速率控制过程。在这项工作中，通过考虑位错迁移行为和筏式微结构，建立了基于热力学和动力学计算并使用现有详细位错动力学模型的最小蠕变速率模型，