Role of coherency loss on rafting behavior of Ni-based superalloys
M. A. Ali, J. V. Görler, I. Steinbach.
The role of coherency loss on rafting of superalloys under high temperature low stress creep conditions is investigated by phase-field crystal plasticity simulations. It is demonstrated that coalescence, critically depending on the state of coherency between precipitate and matrix is crucial to understand the rafting behavior of superalloys. An explicit mechanisms is developed predicting coherency loss based on the plastic activity in the matrix. The simulations are verified using experimental creep test results.
Three dimensional results of re-precipitation of γ' particles in the plastic strain cage(left) and evolved microstructure(right). The amount of plastic strain is displayed in the matrix and γ' is being in white color.